CN114870918A

CN114870918A - Microfluidic chip and application thereof

Info

Publication number: CN114870918A
Application number: CN202210518423.7A
Authority: CN
Inventors: 杜学敏; 王芳; 刘美金; 赵启龙
Original assignee: Shenzhen Institute of Advanced Technology of CAS
Current assignee: Shenzhen Institute of Advanced Technology of CAS
Priority date: 2022-05-13
Filing date: 2022-05-13
Publication date: 2022-08-09

Abstract

The application provides a microfluidic chip and an application thereof, wherein the microfluidic chip comprises a first chip channel layer, the first chip channel layer comprises a piezoelectric material, and the first chip channel layer is provided with a first liquid drop channel; or the micro-fluidic chip comprises a second chip channel layer and a photoacoustic response layer arranged on the surface of the second chip channel layer, the photoacoustic response layer comprises a piezoelectric material, the surface of one side, close to the photoacoustic response layer, of the second chip channel layer is provided with a pore structure, and the pore structure is combined with the photoacoustic response layer to form a second droplet channel; the piezoelectric coefficient of the piezoelectric material is greater than or equal to 1 pC.N ^‑1 . The micro-fluidic chip can drive the liquid drops through illumination or sound, simplifies the control method of the liquid drops, and has the advantages of portability, long-distance high-speed liquid drop control.

Description

Microfluidic chip and application thereof

Technical Field

The application relates to the technical field of microfluidics, in particular to a microfluidic chip and application thereof.

Background

The micro-fluidic technology is a technology for controlling micro-fluid by using a micro-tube, and is successfully applied to the fields of biomedicine, organic synthesis, chemical analysis, micro-reactors and the like at present. The liquid drops in the microfluidic chip have the characteristics of small volume, high flow speed and easy deformation, and at present, the control modes of the liquid drops in the microfluidic chip include air pressure drive, centrifugal drive, electroosmosis drive and hot air drive. Therefore, there is a need to provide a new microfluidic control platform to simplify the droplet control method and achieve flexible droplet control.

Disclosure of Invention

In order to solve the problems, the application provides a microfluidic chip which can drive liquid drops through light, simplify a control method of the liquid drops, can realize high-speed and remote movement of the liquid drops and is beneficial to popularization and application of a microfluidic technology.

Specifically, the first aspect of the present application provides a microfluidic chip comprising

A first chip channel layer comprising a piezoelectric material, the first chip channel layer having a first droplet channel;

or the microfluidic chip comprises a second chip channel layer and a photoacoustic response layer arranged on the surface of the second chip channel layer, the photoacoustic response layer comprises a piezoelectric material, the surface of one side, close to the photoacoustic response layer, of the second chip channel layer is provided with a pore structure, and the pore structure is combined with the photoacoustic response layer to form a second droplet channel; the piezoelectric coefficient of the piezoelectric material is greater than or equal to 1 pC.N ^-1 。

The micro-fluidic chip comprises a piezoelectric material, wherein the polarized piezoelectric material can generate temperature change under illumination and then generate an electric field gradient, or the polarized piezoelectric material can generate temperature change and sound-electricity conversion under sound stimulation and then generate the electric field gradient, and liquid drops can move along with the movement of an illumination site or a sound stimulation site under the action of electrostatic force; the piezoelectric coefficient of the piezoelectric material is greater than or equal to 1 pC.N ^-1 The piezoelectric material has good response to light and sound, thereby ensuring that the light or sound can effectively control the droplet movement. The micro-fluidic chip can be combined with a laser beam or an ultrasonic probe to realize the control of the liquid drop, thereby simplifying the control method of the liquid drop and realizing the accurate control of the liquid drop.

Optionally, the material of the first chip channel layer includes a piezoelectric material.

Optionally, a surface of the first droplet channel is coated with a piezoelectric material.

Optionally, the piezoelectric material comprises one or more of an organic piezoelectric material and an inorganic piezoelectric material.

Optionally, the piezoelectric coefficient d of the organic piezoelectric material ₃₃ Greater than or equal to 10 pC.N ^-1 。

Optionally, the piezoelectric coefficient d of the inorganic piezoelectric material ₃₃ Greater than or equal to 30 pC.N ^-1 。

Optionally, the organic piezoelectric material includes one or more of polyvinylidene fluoride, polyvinylidene fluoride copolymer, polytetrafluoroethylene, nylon with odd number of carbon atoms, polyacrylonitrile, polyimide, polyvinylidene cyanide, polyurea, polyphenylcyano ether, polyvinyl chloride, polyvinyl acetate, polypropylene, polyacrylamide, and ferroelectric liquid crystal.

Optionally, the polyvinylidene fluoride copolymer comprises polyvinylidene fluoride-trifluoroethylene copolymer, polyvinylidene fluoride-tetrafluoroethylene copolymer, polyvinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene copolymer and polyvinylidene fluoride-trifluoroethylene-chlorofluoroethylene copolymer.

Optionally, the inorganic piezoelectric material includes one or more of lead titanate, barium titanate, potassium niobate, lithium tantalate, bismuth titanate, bismuth layer-like perovskite structure ferroelectric, tungsten bronze type ferroelectric, bismuth ferrite, potassium dihydrogen phosphate, ammonium triglycinate sulfate, rhodinate, perovskite type organic metal halide ferroelectric, and the doped compound.

Optionally, the piezoelectric material comprises a pyroelectric material, and the pyroelectric material comprises one or more of an organic pyroelectric material and an inorganic pyroelectric material.

Optionally, the organic pyroelectric material has a pyroelectric coefficient of 10 μ C.m or more ^-2 ·K ^-1 。

Optionally, the inorganic pyroelectric material has a pyroelectric coefficient of greater than or equal to 30 μ C · m ^-2 ·K ^-1 。

Optionally, the first chip channel layer further includes a photo-thermal material.

Optionally, the photoacoustic response layer further comprises a photo-thermal material.

Optionally, the photothermal conversion rate of the photothermal material is 0.1% to 99.99%.

Optionally, the photothermal material includes one or more of a metal photothermal nanomaterial, an inorganic non-metal photothermal nanomaterial, and a high polymer photothermal material.

Optionally, the metal photothermal nanomaterial comprises one or more of a gold nanomaterial and a palladium nanomaterial.

Optionally, the gold nanomaterial comprises one or more of a gold nanorod, a gold nanoshell, a gold nanocage and a hollow gold nanosphere, and the palladium nanomaterial comprises one or more of a palladium nanosheet, a palladium nanoshell, palladium @ silver and palladium @ silicon dioxide.

Optionally, the inorganic non-metallic photo-thermal nano-material comprises Fe ₂ O ₃ 、CuO、MnO ₂ 、WO ₃ One or more of MXene, black phosphorus, copper sulfide, molybdenum sulfide, bismuth sulfide, antimony sulfide, gold sulfide copper selenide, molybdenum selenide, bismuth selenide, antimony selenide, gold selenide, strontium ruthenate, carbon nanotubes, graphene oxide, and carbon black.

Optionally, the high molecular polymer material includes one or more of polydopamine, indocyanine green and polyaniline.

Optionally, the mass ratio of the pyroelectric material to the photothermal material is greater than or equal to 1.

Optionally, the first droplet channel is filled with a lubricant.

Optionally, the second droplet passage is filled with a lubricant.

Optionally, the lubricant comprises vegetable oil, glycol, polyethylene glycol, perfluoropolyether, mineral oil, glycerol, paraffin, N-dodecane, N-dodecene, hexadecene, long chain lubricant, polyurethane, acrylic polyurethane, fluorine oil, vegetable seed oil, N-decanol, motor oil, kerosene, oleic acid, methyl oleate, ethyl oleate, fatty acid amide, stearic acid, stearamide, N-ethylene bis stearamide, oleamide, butyl stearate, glycerol trihydroxystearate, polyester, synthetic ester, carboxylic acid, silicate ester, phosphate ester, synthetic hydrocarbon oil, ferrofluid, thermotropic liquid crystal, ionic liquid, iodoacetic acid, mannitol, eicosapentaenoic acid, algin, alginic acid, mucopolysaccharide, hyaluronic acid, collagen, elastin, allantoin, glucuronic acid, glycolic acid, collagen, mushroom fluid, One or more of emodin, sea tangle mucus, snail mucus and silicone oil.

Optionally, the thickness of the photoacoustic response layer is 1 μm to 10 cm.

Optionally, the material of the chip channel layer includes inorganic glass, transparent ceramic, transparent wood, organic glass, polyvinyl chloride, polystyrene, polycarbonate, polyethersulfone, polypropylene, polyamide, polyurethane, polyimide, polyethylene terephthalate-1, 4-cyclohexanedimethanol ester, one or more of styrene-acrylonitrile copolymer, styrene-methyl methacrylate copolymer, acrylonitrile-butadiene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, diallyl diglycol carbonate polymer, polymethyl-1-pentene, polytetrafluoroethylene, polyvinylidene fluoride, transparent resin, epoxy resin, phenol resin, unsaturated polyester resin, cellulose acetate, cellulose nitrate and ethylene-vinyl acetate copolymer.

A second aspect of the present application provides a method of manipulating droplets, comprising:

providing a light source and the microfluidic chip of the first aspect, wherein a droplet channel of the microfluidic chip contains a droplet, an illumination site is formed in the droplet channel by using the light source, and the droplet moves to the illumination site;

or the manipulation method of the droplets comprises: providing a sound source and the microfluidic chip as described in the first aspect, wherein a droplet channel of the microfluidic chip contains a droplet, a sound stimulation site is formed in the droplet channel by using the sound source, and the droplet moves to the sound stimulation site.

Optionally, the volume of the droplet is 1nL to 100 μ L.

Optionally, the surface tension of the droplets is 10mN · m ^-1 ～100mN·m ^-1 。

Optionally, the liquid drop includes any one of a water drop, an organic matter liquid drop, an inorganic matter solution liquid drop, a micro-nano particle suspension liquid drop, and a biological tissue liquid drop.

Optionally, the organic droplets include one or more of ethanol, acetone, chloroform, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, n-hexane, silicone oil, fluoro oil, sunflower seed oil, olive oil, n-hexadecane, heptane, octane, acetic acid, toluene, diethyl ether, ethyl acetate, butanol, ethylene glycol, isopropanol, and glycerol.

Optionally, the inorganic solution droplets include one or more of sodium chloride, calcium chloride, copper sulfate, magnesium chloride, magnesium sulfate, sodium hydroxide, hydrochloric acid, and potassium hydroxide.

Optionally, the micro-nano particle suspension liquid drop includes one or more of polystyrene spheres, silica spheres and gold particles.

Optionally, the biological tissue fluid drop comprises one or more of blood, serum, cell-containing tissue fluid and cell-containing culture fluid.

Optionally, the wavelength of the light source is 150nm to 4000 nm.

Optionally, the illumination intensity of the light source is 1mW to 20000 mW.

Optionally, the sound source includes ultrasonic waves, and the ultrasonic power of the ultrasonic waves is 1W to 1000W.

A third aspect of the present application provides a method for manufacturing a microfluidic chip, the method comprising:

mixing a piezoelectric material with a solvent to obtain a mixed solution, solidifying the mixed solution to obtain a base layer containing the piezoelectric material, and carrying out polarization treatment on the base layer containing the piezoelectric material to obtain a photoacoustic response layer;

and providing a chip channel layer, and combining and packaging the chip channel layer and the photoacoustic response layer to obtain the microfluidic chip.

Or the preparation method comprises the following steps: mixing a piezoelectric material with a solvent to obtain a mixed solution, solidifying the mixed solution to obtain a base layer containing the piezoelectric material, and carrying out polarization treatment on the base layer containing the piezoelectric material to obtain a first chip channel layer, thus obtaining the micro-fluidic chip.

Or the preparation method comprises the following steps: providing a chip channel layer, wherein the chip channel layer is provided with a liquid drop channel, coating a piezoelectric material on the surface of the liquid drop channel, and carrying out polarization treatment on the piezoelectric material to obtain the microfluidic chip.

Optionally, the polarization treatment comprises one or more of irradiation treatment, electric treatment, magnetic treatment and external force treatment.

Optionally, the external force treatment comprises one or more of pressure, tension, flexing force and ultrasound.

Optionally, the preparation method further comprises: and infiltrating the droplet channel of the chip channel layer with a lubricant to form a lubricating layer on the surface of the droplet channel.

Optionally, the bonding manner of the chip channel layer and the photoacoustic response layer includes one or more of oxygen plasma surface treatment, chloroform bonding, and double-sided adhesive tape bonding.

The application of the microfluidic chip in the first aspect provides the application of the microfluidic chip in biological detection and chemical detection of the microfluidic chip control system.

Drawings

Fig. 1 is a schematic structural diagram of a microfluidic chip provided in an embodiment of the present application;

fig. 2 is an exploded view of a microfluidic chip provided in an embodiment of the present application;

fig. 3 is an exploded view of a microfluidic chip provided in an embodiment of the present application;

fig. 4 is a schematic plan view of a second chip channel layer according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present disclosure;

fig. 7 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Droplet microfluidic chips have been currently used in the fields of chemical reactions, synthesis of nanoparticles and biomaterials, cell sorting and analysis, enzyme analysis, and drug screening. The existing liquid drop control mode is relatively complex, the operation of a precise pump valve is mostly depended, and the development of a simple, efficient and precise liquid drop control technology is the premise and the key for the wide application of a liquid drop microfluidic chip. In order to realize simple and convenient operation of liquid drops at a long distance and a high speed, the application provides the micro-fluidic chip which can generate electric field gradient and trigger the movement of the liquid drops under illumination, and the liquid drops can be directionally moved by setting illumination sites, so that the flexible control of the liquid drops is realized.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present disclosure, where the microfluidic chip includes a first chip channel layer 11, the first chip channel layer has a first droplet channel, and the first chip channel layer includes a piezoelectric material. In some embodiments of the present application, the material of the first chip channel layer includes a piezoelectric material. In some embodiments of the present application, a piezoelectric material overlies a surface of a first droplet channel of a first chip channel layer.

Referring to fig. 2, fig. 2 is an exploded view of a microfluidic chip according to an embodiment of the present disclosure, where the microfluidic chip includes a second chip channel layer 20 and a photoacoustic response layer 10 disposed on a surface of the second chip channel layer 20, the photoacoustic response layer includes a piezoelectric material, a side surface of the second chip channel layer 20 close to the photoacoustic response layer 10 has a pore structure a, and the pore structure a is combined with the photoacoustic response layer 10 to form a second droplet channel, that is, the second droplet channel is formed by the chip channel layer and the photoacoustic response layer. Referring to fig. 3, fig. 3 is an exploded view of a microfluidic chip according to an embodiment of the present disclosure, where the microfluidic chip includes a chip cover plate 30, a second chip channel layer 20, a photoacoustic response layer 10, and a chip bottom plate 40, where the chip cover plate 30 is provided with an a through hole and a B through hole, and the a through hole and the B through hole are communicated with a pore structure of the second chip channel layer 20, that is, projections of the a through hole and the B through hole on the chip channel layer fall in the pore structure, and in an actual application of the microfluidic chip, a droplet or a lubricant may be injected into the second chip channel layer 20 through the a through hole or the B through hole.

In the embodiment of the application, the microfluidic chip comprises a piezoelectric material, dipoles in the material are orderly arranged after the piezoelectric material is polarized, so that liquid drops in a liquid drop channel are subjected to positive and negative charge separation; when the photoacoustic response layer or the liquid drop channel is illuminated, the piezoelectric material is subjected to temperature change under illumination, an electric field gradient is generated along with the temperature change, and the liquid drop moves under the driving of electrostatic force; or when the photoacoustic response layer or the liquid drop channel is subjected to sound stimulation, the piezoelectric material generates temperature change and sound-electricity conversion under the sound stimulation, an electric field gradient is generated, and the liquid drop moves under the driving of electrostatic force, so that the liquid drop can directionally move by arranging an illumination point or a sound stimulation point. In some embodiments of the present application, a laser pen is used to irradiate the droplet channel, the droplet can move along with the irradiation point, and the larger the wavelength of light is, the higher the irradiation intensity is, and the faster the droplet moves. In some embodiments of the present application, an ultrasonic probe is used to approach the droplet channel, the droplet can move along with the sound stimulation site, and the power of the ultrasonic wave is higher, the moving speed of the droplet is higher.

In the embodiment of the present application, the polarization treatment of the piezoelectric material includes one or more of irradiation treatment, electric treatment, magnetic treatment, and external force treatment. In the embodiment of the present application, the piezoelectric coefficient of the piezoelectric material is 1 pC.N or more ^-1 Wherein, pressThe sign of the electrical coefficient being d ₃₃ I.e. d ₃₃ ≥1pC·N ^-1 . The larger the piezoelectric coefficient of the piezoelectric material is, the larger the electrostatic force applied to the liquid droplet is, and the faster the moving speed of the liquid droplet is, which is more beneficial to efficiently controlling the liquid droplet. In the embodiments of the present application, the piezoelectric material includes one or more of an organic piezoelectric material and an inorganic piezoelectric material, and the piezoelectric coefficient of the organic piezoelectric material is 10pC · N or more ^-1 The pyroelectric coefficient of the organic piezoelectric material may specifically be, but not limited to, 10pC · N ^-1 、15pC·N ^-1 、17pC·N ^-1 、20pC·N ^-1 、25pC·N ^-1 、40pC·N ^-1 Or 50 pC.N ^-1 . In some embodiments of the present application, the piezoelectric coefficient of the inorganic piezoelectric material is greater than or equal to 30 pC.N ^-1 The piezoelectric coefficient of the inorganic piezoelectric material may specifically be, but not limited to, 30pC · N ^-1 、50pC·N ^-1 、80pC·N ^-1 、100pC·N ^-1 、150pC·N ^-1 、200pC·N ^-1 、300pC·N ^-1 、500pC·N ^-1 Or 700 pC.N ^-1 。

In some embodiments, the organic piezoelectric material comprises polyvinylidene fluoride, polyvinylidene fluoride copolymer, polytetrafluoroethylene, nylon with an odd number of carbon atoms, polyacrylonitrile, polyimide, polyvinylidene cyanide, polyurea, polyphenylcyanoether, polyvinyl chloride, polyvinyl acetate, polypropylene, polyacrylamide, ferroelectric liquid crystal, and one or more of the above copolymers. In some embodiments of the present application, the polyvinylidene fluoride copolymer comprises one or more of polyvinylidene fluoride-trifluoroethylene copolymer, polyvinylidene fluoride-tetrafluoroethylene copolymer, polyvinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene copolymer, and polyvinylidene fluoride-trifluoroethylene-chlorofluoroethylene copolymer.

In some embodiments of the present application, the inorganic piezoelectric material includes one or more of lead titanate, barium titanate, potassium niobate, lithium tantalate, bismuth titanate, bismuth layer-structured perovskite ferroelectrics, tungsten bronze type ferroelectrics, bismuth ferrite, potassium dihydrogen phosphate, ammonium trinitrate sulfate, rosette, perovskite type organic metal halide ferroelectrics, and doped compounds thereof. In the embodiment of the present application, the particle size of the inorganic piezoelectric material is 1nm to 100 μm. The particle size of the inorganic piezoelectric material may specifically be, but not limited to, 1nm, 10nm, 50nm, 100nm, 500nm, 1 μm, 10 μm, or 100 μm.

In some embodiments of the present application, the piezoelectric material comprises a pyroelectric material having a pyroelectric coefficient of 1 μ C · m or more ^-2 ·K ^-1 Wherein the sign of the pyroelectric coefficient is p, i.e. p is more than or equal to 1 mu C.m ^-2 ·K ^-1 . The pyroelectric material can be subjected to temperature change under illumination, an electric field gradient is generated along with the temperature change, and the liquid drops move under the driving of electrostatic force, so that the liquid drops can move directionally by setting illumination points. In some embodiments of the present application, the pyroelectric material comprises one or more of an organic pyroelectric material and an inorganic pyroelectric material, and the pyroelectric coefficient of the organic pyroelectric material is greater than or equal to 10 μ C · m ^-2 ·K ^-1 The pyroelectric coefficient of the organic pyroelectric material may be specifically, but not limited to, 10. mu.C.m ^-2 ·K ^-1 、15μC·m ^-2 ·K ^-1 、17μC·m ^-2 ·K ^-1 、20μC·m ^-2 ·K ^-1 、25μC·m ^-2 ·K ^-1 、40μC·m ^-2 ·K ^-1 Or 50 μ C · m ^-2 ·K ^-1 . In some embodiments of the present application, the inorganic pyroelectric material has a pyroelectric coefficient of 30 μ C · m or more ^-2 ·K ^-1 The pyroelectric coefficient of the inorganic pyroelectric material may specifically but not exclusively be 30 μ C · m ^-2 ·K ^-1 、50μC·m ^-2 ·K ^-1 、80μC·m ^-2 ·K ^-1 、100μC·m ^-2 ·K ^-1 、150μC·m ^-2 ·K ^-1 、200μC·m ^-2 ·K ^-1 、300μC·m ^-2 ·K ^-1 、500μC·m ^-2 ·K ^-1 Or 700. mu.C.m ^-2 ·K ^-1 。

In some embodiments of the present application, the microfluidic chip further includes a photo-thermal material, and the photo-thermal material may be in the first chip channel layer or in the photo-acoustic response layer, for example, when the pyroelectric material is located in the first chip channel layer, the photo-thermal material is also located in the first chip channel layer, and when the pyroelectric material is located in the photo-acoustic response layer, the photo-thermal material is also located in the photo-acoustic response layer. The photo-thermal material is added into the micro-fluidic chip, so that the photo-thermal conversion efficiency can be improved, the light energy can be more efficiently converted into heat energy, and the pyroelectric material is excited to generate an electric field gradient, so that the electric field intensity is improved, the electrostatic force borne by the liquid drop is enhanced, and the liquid drop can rapidly respond to illumination. In some embodiments of the present application, the photothermal material has a photothermal conversion ratio of 0.1% to 99.99%. In some embodiments, the photo-thermal material comprises one or more of a metal photo-thermal nanomaterial, an oxide photo-thermal nanomaterial, a carbon nanomaterial, a high molecular polymer material, and a semiconductor nanomaterial. In some embodiments of the present application, the metallic photothermal nanomaterial comprises one or more of a gold nanomaterial and a palladium nanomaterial. In some embodiments of the present application, the gold nanomaterials comprise one or more of gold nanorods, gold nanoshells, gold nanocages, and hollow gold nanospheres. In some embodiments of the present application, the palladium nanomaterial comprises one or more of palladium nanoplatelets, palladium nanoshells, palladium @ silver, and palladium @ silica, wherein palladium @ silver represents a silver-coated palladium core-shell nanomaterial and palladium @ silica represents a silica-coated palladium core-shell nanomaterial. In some embodiments, the photoacoustic response layer includes polyvinylidene fluoride copolymer and polydopamine; in some embodiments, the photoacoustic response layer includes polyvinylidene fluoride copolymer and gold nanomaterial.

In the application, when the microfluidic chip comprises the photo-thermal material, the mass ratio of the pyroelectric material to the photo-thermal material is 100: 0-50: 50 (excluding 100: 0). The mass ratio of the pyroelectric material to the photothermal material may be, but not limited to, 100:1, 95:5, 90:10, 80:20, 75:25, or 70: 30. In the mass ratio range, the photo-thermal material can realize good matching effect with the piezoelectric material, and the liquid drop can be effectively controlled by illumination.

In the embodiment of the present application, the chip channel layer is made of a transparent material. In some embodiments of the present application, the material of the channel layer of the chip comprises inorganic glass, transparent ceramic, transparent wood, organic glass, polyvinyl chloride, polystyrene, polycarbonate, polyether sulfone, polypropylene, polyamide, polyurethane, polyimide, polyethylene terephthalate-1, 4-cyclohexanedimethanol, one or more of styrene-acrylonitrile copolymer, styrene-methyl methacrylate copolymer, acrylonitrile-butadiene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, diallyl diglycol carbonate polymer, polymethyl-1-pentene, polytetrafluoroethylene, polyvinylidene fluoride, transparent resin, epoxy resin, phenol resin, unsaturated polyester resin, cellulose acetate, cellulose nitrate and ethylene-vinyl acetate copolymer.

Referring to fig. 4, fig. 4 is a schematic plan view of a second chip channel layer according to an embodiment of the present disclosure, in which a side surface of the second chip channel layer 20 close to the photoacoustic response layer has a via structure, and the via structure and the photoacoustic response layer are combined to form a closed channel, i.e., a droplet channel 21. In the present application, the shape and position of the droplet channel can be set according to the application requirement, and is not limited herein. In some embodiments of the present disclosure, the channel structure of the chip channel layer is prepared by one or more methods of photolithography and micromachining, machining, laser cutting, template coating, and 3D printing.

In some embodiments of the present application, the droplet channel is filled with a lubricant, wherein the lubricant may be completely filled or partially filled, where completely filled means that the lubricant fills the entire droplet channel, and partially filled means that the lubricant forms a lubricating layer only on the surface of the droplet channel. Filling the droplet channel with lubricant can reduce the resistance of the droplet moving in the channel, thereby improving the moving speed of the droplet. In some embodiments of the present application, the droplet channel is filled with the lubricant, which can improve the biocompatibility of the droplet channel and ensure the stable reaction in the microfluidic chip.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present disclosure, in fig. 5, a lubricant forms a lubricating layer 22 on a surface of a droplet channel 21. In some embodiments of the present application, the lubricating layer has a thickness of 1nm to 100 μm. Because the promotion effect of lubricant bed to liquid speed is limited, and the stability of lubricant bed is relatively poor, is difficult for fixing in the liquid droplet passageway, in some embodiments of this application, the liquid droplet passageway is filled completely to the emollient, and when the liquid droplet passageway was filled with the emollient, the liquid droplet soaked and carries out the motion in the emollient to greatly reduced liquid droplet's motion resistance, it needs to be noted that the liquid droplet is not compatible with the emollient, so the liquid droplet can move under the control of light. Referring to fig. 6, fig. 6 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present application, and in fig. 6, a lubricant completely fills a droplet channel 21 of the microfluidic chip.

Referring to fig. 7, fig. 7 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present application, in fig. 7, a lubricant completely fills a droplet channel 21, a droplet floats in the lubricant, and the droplet can be directionally moved to an illumination point by illuminating the microfluidic chip.

In some embodiments of the present application, the lubricant comprises vegetable oils, glycols, polyethylene glycols, perfluoropolyethers, mineral oils, glycerol, paraffin, N-dodecane, N-dodecene, hexadecene, long chain lubricants, polyurethanes, acrylic polyurethanes, fluoro oils, vegetable seed oils, N-decanol, motor oils, kerosene, oleic acid, methyl oleate, ethyl oleate, fatty acid amides, stearic acid, stearamides, N-ethylene bis stearamides, oleamides, butyl stearates, glycerol trihydroxystearates, polyesters, synthetic esters, carboxylic acids, silicates, phosphate esters, synthetic hydrocarbon oils, ferrofluids, thermotropic liquid crystals, ionic liquids, iodoacetic acid, mannitol, eicosapentaenoic acid, algin, alginic acid, mucopolysaccharides, hyaluronic acid, collagen, elastin, allantoin, glucuronic acid, glycolic acid, glycerol, and mixtures thereof, One or more of ossein, mushroom liquid, emodin, sea tangle mucus, snail mucus and silicone oil.

The liquid drop micro-fluidic platform provided by the application utilizes the temperature change of the polarized piezoelectric material under illumination, and then generates an electric field gradient, or the temperature change and the sound-electricity conversion of the polarized piezoelectric material under the stimulation of sound, and then induces the electric field gradient to trigger the movement of liquid drops in a micro-fluidic chip channel. The polarized piezoelectric material can quickly generate an electric field to cause the liquid drop to quickly move for a long distance, and the piezoelectric material has wide response wavelength to light and wide required illumination energy density, so that the portable laser pen can also realize control without a complex pump valve structure, thereby greatly expanding the application range of the current liquid drop microfluidic platform and reducing the manufacturing cost and the application difficulty of the liquid drop microfluidic platform.

The present application also provides a method of manipulating droplets, which in some embodiments comprises: and injecting liquid drops into the liquid drop channel of the microfluidic chip, irradiating the liquid drop channel to form an illumination site, and moving the liquid drops to the illumination site. In some embodiments, a method of manipulating droplets comprises: and injecting liquid drops into a liquid drop channel of the microfluidic chip, forming sound stimulation sites in the liquid drop channel by adopting an ultrasonic probe, and moving the liquid drops to the sound stimulation sites. In the application, when the micro-fluidic chip is irradiated or acoustically stimulated, the temperature of an illumination site or an acoustic stimulation site is higher, the piezoelectric material generates a high-intensity central electric field, the liquid drop moves to the stimulation site under the action of electrostatic force, the closer the distance between the stimulation site and the liquid drop is, the higher the moving speed of the liquid drop is, and the liquid drop can move along an optical or acoustic moving path by setting the moving track of a light source or an acoustic source, so that the non-contact control of the liquid drop is realized.

In some embodiments of the present disclosure, the light source used to illuminate the microfluidic chip has a wavelength of 150nm to 4000 nm. In some embodiments of the present disclosure, the light source used to illuminate the microfluidic chip has a wavelength of 500nm to 980 nm. In some embodiments of the present application, the illumination intensity of the light source is 1mW to 20000mW, and the illumination intensity of the light source may specifically but not limited to be 1mW, 10mW, 100mW, 1000mW, 5000mW, 10000mW or 20000 mW. In some embodiments of the present application, the sound source for performing the sound stimulation on the microfluidic chip is ultrasonic waves, the power of the ultrasonic waves is 1W to 1000W, and the power of the ultrasonic waves may be, but is not limited to, 1W, 10W, 30W, 100W, 200W, 500W, or 1000W.

In some embodiments of the present application, the volume of the droplet in the droplet channel is 1nL to 100. mu.L, and the volume of the droplet may specifically be, but not limited to, 1nL, 10nL, 100nL, 1. mu.L, 10. mu.L or 100. mu.L,the liquid drops with the volumes are easy to control, and flexible and rapid movement can be realized under the action of the micro-fluidic chip and light. In some embodiments of the present application, the surface tension of the droplet is 10mN · m ^-1 ～100mN·m ^-1 . In some embodiments of the present application, the liquid droplet includes any one of a water droplet, an organic liquid droplet, an inorganic solution droplet, a micro-nano particle suspension liquid droplet, and a biological tissue liquid droplet, wherein the organic liquid droplet may be an organic solvent liquid droplet. In some embodiments of the present application, the organic droplets comprise one or more of ethanol, acetone, chloroform, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, n-hexane, silicone oil, fluoro oil, sunflower seed oil, olive oil, n-hexadecane, heptane, octane, acetic acid, toluene, diethyl ether, ethyl acetate, butanol, ethylene glycol, isopropanol, and glycerol; in the inorganic solution droplets, the solute of the inorganic solution comprises one or more of sodium chloride, calcium chloride, copper sulfate, magnesium chloride, magnesium sulfate, sodium hydroxide, hydrochloric acid and potassium hydroxide; the micro-nano particles in the micro-nano particle suspension liquid drop comprise one or more of polystyrene spheres, silica spheres and gold particles; the biological tissue fluid drop comprises one or more of blood, serum, tissue fluid containing cells and culture fluid containing cells. The liquid drop control method is suitable for various liquid drops, and the control device is simple and convenient, has excellent space-time resolution, and is favorable for application of the liquid drop control method in a digital light control micro-fluidic system, biological and chemical detection, molecular biology and analytical chemistry.

The present application also provides a method of preparing a microfluidic chip, which in some embodiments comprises:

step 100: mixing a piezoelectric material with a solvent to obtain a mixed solution, solidifying the mixed solution to obtain a base layer containing the piezoelectric material, and carrying out polarization treatment on the base layer containing the piezoelectric material to obtain a photoacoustic response layer;

step 200: and providing a chip channel layer, combining the chip channel layer with the photoacoustic response layer and packaging to obtain the microfluidic chip.

In step 100, the piezoelectric material includes one or more of an organic piezoelectric material and an inorganic piezoelectric material. In the embodiments of the present application, the solvent includes one or more of ethylene glycol methyl ether, glacial acetic acid, dimethyl sulfoxide, N-dimethylformamide acetone, trimethyl phosphate, N-dimethylformamide, N-dimethylacetamide, propylene glycol, N-methylpyrrolidone, tetrahydrofuran, tetramethylurea, hexamethylphosphoric acid amide, and hexafluoroisopropanol. In some embodiments of the present disclosure, the mass concentration of the piezoelectric material in the mixed solution is 1% to 50%. The mass concentration of the piezoelectric material may specifically be, but not limited to, 1%, 5%, 10%, 20%, 30%, 40%, or 50%. In some embodiments of the present application, the solidifying of the mixed liquid includes: casting or spin-coating the mixed solution on a substrate, drying and annealing to obtain a base layer containing the piezoelectric material, and polarizing the base layer containing the piezoelectric material to obtain the photoacoustic response layer, wherein the substrate can be a planar substrate or a substrate with a microstructure. In some embodiments of the present application, the mixed solution further includes a photo-thermal material, and the photo-acoustic response layer may be prepared by dispersing the piezoelectric material and the photo-thermal material in a solvent to obtain a mixed solution, casting or spin-coating the mixed solution to obtain a base layer containing the piezoelectric material, and then polarizing to obtain the photo-acoustic response layer.

In some embodiments, a method of preparing a microfluidic chip comprises:

step 100: and pressing the piezoelectric material into a film, and polarizing to obtain the photoacoustic response layer.

In some embodiments of the present application, the polarization treatment comprises one or more of irradiation treatment, electrical treatment, magnetic treatment, and external force treatment, wherein the external force treatment comprises one or more of pressure, tension, deflection, and ultrasound.

In step 200, the surface of the chip channel layer is provided with a pore structure, the chip channel layer and the photoacoustic response layer are combined and packaged to obtain the droplet channel, and the pore structure can be prepared by one or more methods of photoetching micromachining, machining, laser cutting, template coating and 3D printing. In some embodiments, the chip channel layer and the photoacoustic response layer may be bonded by one or more of oxygen plasma surface treatment, chloroform bonding, or double-sided adhesive bonding. In some embodiments of the present application, the method for preparing a microfluidic chip further comprises: and (3) filling a liquid drop channel of the chip channel layer with a lubricant, and filling the lubricant in the liquid drop channel. In the present application, the lubricant is incompatible with the droplets. In some embodiments of the present application, the lubricant comprises one or more of a perfluorooil, a vegetable oil, a vegetable seed oil, n-decanol, ethylene glycol, motor oil, kerosene, mineral oil, oleic acid, methyl oleate, ethyl oleate, ferrofluid, paraffin, thermotropic liquid crystal, ionic liquid, silicone oil.

In some embodiments, a method of preparing a microfluidic chip comprises:

and mixing the piezoelectric material with a solvent to obtain a mixed solution, solidifying the mixed solution to obtain a base layer containing the piezoelectric material, and carrying out polarization treatment on the base layer containing the piezoelectric material to obtain a first chip channel layer, namely the microfluidic chip.

In some embodiments, a method of preparing a microfluidic chip comprises:

and providing a chip channel layer, wherein the chip channel layer is provided with a liquid drop channel, coating a piezoelectric material on the surface of the liquid drop channel, and carrying out polarization treatment on the piezoelectric material to obtain the microfluidic chip.

The preparation method of the microfluidic chip is simple to operate, controllable in process and suitable for industrial production.

The following further describes embodiments of the present application in terms of a number of examples.

Example 1

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein a pyroelectric material in the photoacoustic response layer is polyvinylidene fluoride (PVDF), and the pyroelectric coefficient p of the PVDF is 20 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: mixing 10 wt% of PVDF is dissolved in N, N-dimethylformamide, the solution is cast on the surface of a glass substrate, a film is taken off from the glass substrate after being dried, the film thickness is 100 mu m, the film is stretched by 3 times of elongation to realize polarization, and the pyroelectric coefficient p is obtained to be 20 mu C.m ^-2 ·K ^-1 The PVDF film of (1) was cut to obtain a PVDF film having an area of 15 × 35mm, i.e., a photoacoustic response layer.

2) Preparing a micro-fluidic chip: taking glass with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a photoetching micro-processing method to form a chip channel layer.

Taking unstructured glass with the same size, clamping the PVDF film between the unstructured glass and a chip channel layer, combining the layers through oxygen plasma surface treatment, forming a liquid drop channel by a pore channel structure and the PVDF film, and pouring perfluorinated oil into the liquid drop channel to obtain the microfluidic chip.

Example 2

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the pyroelectric material in the photoacoustic response layer is lead titanate, and the pyroelectric coefficient p of the lead titanate is 100 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: dissolving lead acetate and tetrabutyl titanate in a volume ratio of ethylene glycol monomethyl ether to glacial acetic acid of 1: 1 to obtain 2.5 wt% of lead titanate sol, spin-coating the lead titanate sol on a silicon substrate by a spin coater according to parameters of 3000rpm and 5min, repeating the spin coating for 10 times, and annealing at 750 ℃ to obtain a lead titanate film, wherein the thickness of the lead titanate film is 500 nm; carrying out 5kV direct-current high-voltage electrical treatment on the lead titanate film to realize polarization, and obtaining the pyroelectric coefficient p of 100 mu C.m ^-2 ·K ^-1 The lead titanate film with the silicon substrate is cut to obtain the lead titanate film with the silicon substrate with the area of 20-40 mm.

2) Preparing a micro-fluidic chip: taking organic glass with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a machining method to form a chip channel layer.

And combining a lead titanate film with a silicon substrate and a chip channel layer by using double faced adhesive tape, wherein the lead titanate film is clamped between the chip channel layer and the silicon substrate, the pore channel structure and the lead titanate film form a liquid drop channel, and vegetable oil is filled in the liquid drop channel to obtain the microfluidic chip.

Example 3

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the pyroelectric material in the photoacoustic response layer is barium titanate ceramic, and the pyroelectric coefficient p of the barium titanate ceramic is 50 μ C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: uniformly mixing 95 wt% of barium titanate nano particles and 5 wt% of binder polyvinylpyrrolidone (PVP) by ball milling, and pressing into a ceramic wafer by adopting 300MPa pressure, wherein the thickness of the barium titanate ceramic is 1 mm; carrying out 15kV direct-current high-voltage electrical treatment on the barium titanate ceramic to realize polarization, and obtaining the barium titanate ceramic with the pyroelectric coefficient p of 50 mu C.m ^-2 ·K ^-1 The barium titanate ceramic is cut to obtain the barium titanate ceramic with the area of 20-40 mm.

2) Preparing a micro-fluidic chip: taking organic glass with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 2mm and the height of 2mm by adopting a machining method to form a chip channel layer.

And combining the barium titanate ceramic with the chip channel layer by adopting a double faced adhesive tape, forming a liquid drop channel by the pore channel structure and the barium titanate ceramic, and filling decanol into the liquid drop channel to obtain the microfluidic chip.

Example 4

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein a pyroelectric material in the photoacoustic response layer comprises a composite material of polyvinylidene fluoride and bismuth ferrite, and the pyroelectric coefficient p of the composite material is 1 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: dissolving 10 wt% of polyvinylidene fluoride in N, N-dimethylformamide, dispersing 5 wt% of bismuth ferrite nano powder in polyvinylidene fluoride solution, and making the mixed solution flowDrying the film on a glass substrate, and taking the film from the glass substrate, wherein the thickness of the polyvinylidene fluoride-bismuth ferrite composite film is 100 mu m; carrying out 20kV direct-current high-voltage corona treatment on the composite material film to realize polarization, and obtaining the material with the pyroelectric coefficient p of 15 mu C.m ^-2 ·K ^-1 The polyvinylidene fluoride-bismuth ferrite composite material film is cut to obtain the photoacoustic response layer with the area of 15 x 35 mm.

2) Preparing a micro-fluidic chip: taking polycarbonate with the length of 20mm, the width of 40mm and the height of 3mm, and obtaining a pore channel structure with the width of 2mm and the height of 2mm by adopting a machining method to form a chip channel layer.

Taking unstructured polycarbonate with the same size, clamping the photoacoustic response layer between the unstructured polycarbonate and the chip channel layer, bonding the layers by using double faced adhesive tapes, forming a liquid drop channel by using the pore channel structure and the photoacoustic response layer, and filling ethylene glycol into the liquid drop channel to obtain the microfluidic chip.

Example 5

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the photoacoustic response layer comprises a pyroelectric material polyvinylidene fluoride and a photothermal material gold nanorod, and the pyroelectric coefficient p of the polyvinylidene fluoride is 15 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: dissolving 10 wt% of PVDF in N, N-dimethylformamide, dispersing 0.5 wt% of gold nanorods in the PVDF solution, casting the mixed solution on the surface of a glass substrate, drying, and taking down the composite membrane from the glass substrate, wherein the thickness of the composite membrane is 100 mu m; carrying out 15kV direct-current high-voltage corona treatment on the composite film to realize polarization, and obtaining the pyroelectric coefficient p of 15 mu C.m ^-2 ·K ^-1 The polyvinylidene fluoride-gold nanorod composite membrane is cut to obtain the photoacoustic response layer with the area of 15 x 35 mm.

2) Preparing a micro-fluidic chip: taking a polyether sulfone plate with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a template molding method to form a chip channel layer.

Taking an unstructured polyether sulfone plate with the same size, clamping a photoacoustic response layer between the unstructured polyether sulfone plate and a chip channel layer, bonding the layers by using double faced adhesive tapes, forming a liquid drop channel by using a pore channel structure and the photoacoustic response layer, and pouring silicone oil into the liquid drop channel to obtain the microfluidic chip.

Example 6

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the photoacoustic response layer comprises a pyroelectric material polyvinylidene fluoride-trifluoroethylene copolymer (PVDF-TrFE), barium titanate and a photothermal material polydopamine, and the pyroelectric coefficient p of the pyroelectric material is 20 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: dissolving 10 wt% of PVDF-TrFE in N, N-dimethylformamide, dispersing 5 wt% of polydopamine-coated barium titanate nano powder in PVDF-TrFE solution, casting the mixed solution on a glass substrate, drying, and taking down the composite membrane from the glass substrate, wherein the thickness of the composite membrane is 100 mu m; carrying out 15kV direct-current high-voltage electrical treatment corona treatment on the composite film to realize polarization, and obtaining the composite film with the pyroelectric coefficient p of 20 mu C.m ^-2 ·K ^-1 The PVDF-TrFE/polydopamine @ barium titanate composite membrane is cut to obtain the photoacoustic response layer with the area of 15 x 35 mm.

2) Preparing a micro-fluidic chip: taking a polyether sulfone plate with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a 3D printing method to form a chip channel layer.

Example 7

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the photoacoustic response layer comprises a pyroelectric material polyvinylidene fluoride-trifluoroethylene copolymer (PVDF-TrFE) and polyacrylonitrile, and the pyroelectric coefficient p of the pyroelectric material is 15 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: dissolving 10 wt% of PVDF-TrFE and 5 wt% of polyacrylonitrile in N, N-dimethylformamide, placing the mixed solution in a container, and performing solvent replacement to obtain a composite membrane, wherein the thickness of the composite membrane is 100 micrometers; carrying out 15kV direct-current high-voltage corona treatment on the composite film to realize polarization, and obtaining the pyroelectric coefficient p of 15 mu C.m ^-2 ·K ^-1 The PVDF-TrFE/polyacrylonitrile composite membrane is cut to obtain the photoacoustic response layer with the area of 15 x 35 mm.

2) Preparing a micro-fluidic chip: taking a polyether sulfone plate with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a mechanical processing method to form a chip channel layer.

Example 8

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the photoacoustic response layer comprises pyroelectric materials of lead titanate and bismuth ferrite, and the pyroelectric coefficient p of the pyroelectric materials is 500 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: dissolving lead acetate, tetrabutyl titanate, ferric nitrate and bismuth acetate in ethylene glycol monomethyl ether and glacial acetic acid in a volume ratio of 1: 1, respectively obtaining mixed sol of 2.5 wt% of lead titanate and 2.5 wt% of bismuth ferrite, spin-coating the sol on a silicon substrate by a spin coater at 3000rpm for 5min, repeating spin coating for 10 times, and annealing at 750 ℃ to obtain a lead titanate-bismuth ferrite composite film, wherein the thickness of the composite film is 500 nm; carrying out 5kV direct-current high-voltage electrical treatment on the composite film to realize polarization, and obtaining the pyroelectric coefficient p of 500 mu C.m ^-2 ·K ^-1 The lead titanate-bismuth ferrite composite membrane is cut to obtain the photoacoustic response layer with the area of 15 x 35 mm.

2) Preparing a micro-fluidic chip: taking organic glass with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a mechanical processing method to form a chip channel layer.

And bonding the lead titanate-bismuth ferrite composite film with the silicon substrate with the chip channel layer through a double-sided adhesive tape, wherein the lead titanate-bismuth ferrite composite film is positioned between the silicon substrate and the chip channel layer, the pore channel structure and the lead titanate-bismuth ferrite composite film form a liquid drop channel, and vegetable oil is poured into the liquid drop channel to obtain the microfluidic chip.

Example 9

A micro-fluidic chip comprises a chip channel layer, wherein a pyroelectric material in the chip channel layer is polyvinylidene fluoride (PVDF), and the pyroelectric coefficient p of the PVDF is 20 mu C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

dissolving 10 wt% of PVDF in N, N-dimethylformamide, casting the solution in a PMMA chip die, wherein the die has a pore channel structure with the width of 1mm and the height of 1mm, taking down a film with the pore channel structure from the die after drying, carrying out corona polarization on the film, taking glass with the length of 20mm, the width of 40mm and the height of 2mm, bonding the glass with the film with the pore channel structure to form a chip channel layer, and pouring perfluorinated oil into a liquid drop channel to obtain the microfluidic chip.

Example 10

A microfluidic chip comprises a chip channel layer, wherein the pyroelectric material in the chip channel layer is barium titanate, and the pyroelectric coefficient p of the barium titanate is 50 μ C.m ^-2 ·K ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

the method comprises the steps of obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a photoetching micromachining method for barium titanate single crystals, forming a chip channel layer by taking glass with the length of 20mm, the width of 40mm and the height of 2mm and the barium titanate single crystals, and filling perfluorinated oil into a liquid drop channel to obtain the microfluidic chip.

Example 11

A microfluidic chip comprises a chip channel layer including pyroelectric material barium titanate powder and photo-thermal materialPoly-dopamine, the pyroelectric coefficient p of the pyroelectric material is 20 μ C.m ^-2 ·K ^-1 。

Taking a polyether sulfone plate with the length of 20mm, the width of 40mm and the height of 2mm, obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a 3D printing method, spraying mixed powder of barium titanate powder and polydopamine on the inner wall of a channel layer, then carrying out corona polarization, taking a non-structural polyether sulfone plate with the same size, bonding the polyether sulfone plate with the pore channel structure and the non-structural polyether sulfone plate by adopting double faced adhesive tape to form a liquid drop channel, obtaining a chip channel layer, and pouring silicone oil into the liquid drop channel to obtain the microfluidic chip.

Example 12

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the photoacoustic response layer comprises a piezoelectric material polyvinylidene fluoride, and the piezoelectric coefficient of the polyvinylidene fluoride is 25 pC.N ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: dissolving 10 wt% of PVDF in N, N-dimethylformamide, casting the solution on the surface of a glass substrate, drying, and taking down a film from the glass substrate, wherein the thickness of the film is 100 mu m; the film is processed by 15kV DC high voltage corona treatment to realize polarization, and the obtained piezoelectric coefficient is 25 pC.N ^-1 The polyvinylidene fluoride composite membrane is cut to obtain the photoacoustic response layer with the area of 15 x 35 mm.

Example 13

A micro-fluidic chip comprises a chip channel layer, wherein a piezoelectric material in the chip channel layer is polyvinylidene fluoride (PVDF), and the piezoelectric coefficient of the PVDF is 25 pC.N ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

Example 14

A micro-fluidic chip comprises a chip channel layer and a photoacoustic response layer, wherein the piezoelectric material in the photoacoustic response layer is barium titanate ceramic, and the piezoelectric coefficient p of the barium titanate ceramic is 50 pC.N ^-1 。

The preparation method of the microfluidic chip comprises the following steps:

1) preparing a photoacoustic response layer: uniformly mixing 95 wt% of barium titanate nano particles and 5 wt% of binder polyvinylpyrrolidone (PVP) by ball milling, and pressing into a ceramic wafer by adopting 300MPa pressure, wherein the thickness of the barium titanate ceramic is 1 mm; carrying out 15kV direct-current high-voltage electrical treatment on the barium titanate ceramic to realize polarization, and obtaining the piezoelectric coefficient p of 50 pC.N ^-1 The barium titanate ceramic of (1) is cut to obtain a barium titanate ceramic with an area of 20 x 40 mm.

Comparative example 1

A method of making a droplet microfluidic platform, comprising:

dissolving 10 wt% of polyvinylidene fluoride-trifluoroethylene copolymer (PVDF-TrFE) in N, N-dimethylformamide, dispersing 5 wt% of polydopamine-coated barium titanate nano powder in the PVDF-TrFE solution, casting the mixed solution on a glass substrate, drying, taking down the PVDF-TrFE/polydopamine-coated barium titanate composite membrane from the glass substrate, wherein the thickness of the composite membrane is 100 mu m, and cutting the composite membrane to obtain the composite membrane with the size of 15 x 35 mm.

Taking a polyether sulfone plate with the length of 20mm, the width of 40mm and the height of 2mm, and obtaining a pore channel structure with the width of 1mm and the height of 1mm by adopting a 3D printing method to form a chip channel layer. Taking an unstructured polyether sulfone plate with the same size, clamping an unpolarized composite membrane between the unstructured polyether sulfone plate and a chip channel layer, bonding the layers by using double faced adhesive tapes, and forming a liquid drop channel by using a channel structure and the composite membrane to obtain a liquid drop microfluidic platform.

Effects of the embodiment

In order to verify the performance of the microfluidic chip manufactured by the method, the method also provides an effect embodiment.

1) And injecting liquid drops into the microfluidic chips of examples 1 to 11 and the liquid drop microfluidic platform of the comparative example 1, controlling the liquid drops by using a laser pen, and observing the movement condition of the liquid drops when the illumination point is at the edge of the liquid drops. Taking example 1 as an example, the droplet of example 1 is a water droplet, the size of the water droplet is 1nL, the wavelength λ of light is 4000nm, a laser pen with illumination intensity of 2000mW irradiates a droplet channel, and the movement speed of the droplet in the microfluidic chip is 100 mm/s. See table 1 for specific parameters of each example and comparative example experiment.

2) And injecting liquid drops into the microfluidic chips of examples 12 to 14 and the liquid drop microfluidic platform of comparative example 1, controlling the liquid drops by using an ultrasonic probe, aligning the ultrasonic probe to the edges of the liquid drops at a position of 1cm on the chip, and observing the movement condition of the liquid drops. Taking the example 12 as an example, the droplet of the example 12 is a water droplet, the size of the water droplet is 300nL, the power of the ultrasonic probe is 60W, the droplet in the channel is driven, and the moving speed of the droplet in the acoustic control droplet microfluidic chip is 10 mm/s. For specific parameters of the examples and comparative experiments, see table 1.

TABLE 1 Experimental parameter tables for examples 1-14 and comparative example 1

As can be seen from table 1, the movement speed of the droplet in comparative example 1 is much lower than that of the droplet in example 6, and the structure of the microfluidic platform of the droplet in comparative example 1 is the same as that of the microfluidic chip in example 6, except that the composite film in comparative example 1 is not polarized, and when the composite film is not polarized, the electric field gradient cannot be generated by illumination, that is, the droplet cannot be driven to move by electrostatic force. The reason why the droplet of comparative example 1 can move is that the thermal effect drives the droplet to move, but since the viscous resistance of the droplet movement is large, the driving force of the thermal effect is limited, and the droplet of comparative example 1 moves at a slow speed and over a short distance. When the droplet microfluidic platform of the comparative example 2 is stimulated by sound, the movement speed of the droplet is much lower than that of the droplet in the example 14, and the droplet microfluidic platform of the comparative example 2 and the microfluidic chip of the example 14 have the same structure, except that the composite membrane of the comparative example 2 is not polarized, and the sound stimulation cannot generate an electric field gradient when the composite membrane is not polarized, that is, the droplet cannot be driven to move by electrostatic force. The reason why the liquid droplets of comparative example 2 can move is that the liquid droplets are driven to move by the thermal effect generated by the ultrasound, but the driving force of the thermal effect is limited because the viscous resistance of the liquid droplet movement is large, and the liquid droplets of comparative example 2 move at a slow speed and over a short distance. Experiments show that the micro-fluidic chip can efficiently utilize light to drive liquid drops to realize rapid movement of the liquid drops, is suitable for different types of liquid drops, and can change the movement speed of the liquid drops by adjusting the wavelength of the light, the illumination intensity and the polarization intensity of the piezoelectric material.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A microfluidic chip comprising a first chip channel layer comprising a piezoelectric material, the first chip channel layer having a first droplet channel;

2. The microfluidic chip of claim 1, wherein the material of the first chip channel layer comprises a piezoelectric material.

3. The microfluidic chip of claim 1, wherein a surface of the first droplet channel is coated with a piezoelectric material.

4. The microfluidic chip according to any of claims 1 to 3, wherein the piezoelectric material comprises one or more of an organic piezoelectric material and an inorganic piezoelectric material; the piezoelectric coefficient of the organic piezoelectric material is greater than or equal to 10 pC.N ^-1 (ii) a The piezoelectric coefficient of the inorganic piezoelectric material is greater than or equal to 30 pC.N ^-1 。

5. The microfluidic chip according to claim 4, wherein the organic piezoelectric material comprises one or more of polyvinylidene fluoride, polyvinylidene fluoride copolymer, polytetrafluoroethylene, nylon with odd number of carbon atoms, polyacrylonitrile, polyimide, polyvinylidene cyanide, polyurea, polyphenylcyano ether, polyvinyl chloride, polyvinyl acetate, polypropylene, polyacrylamide, and ferroelectric liquid crystal.

6. The microfluidic chip according to claim 4, wherein the inorganic piezoelectric material comprises one or more of lead titanate, barium titanate, potassium niobate, lithium tantalate, bismuth titanate, bismuth layer-like perovskite structure ferroelectric, tungsten bronze type ferroelectric, bismuth ferrite, potassium dihydrogen phosphate, ammonium trinitrate sulfate, rosette, perovskite type organic metal halide ferroelectric, and doped compounds thereof.

7. The microfluidic chip according to any of claims 1 to 3, wherein said piezoelectric material comprises a pyroelectric material, said pyroelectric material comprising one or more of an organic pyroelectric material and an inorganic pyroelectric material; the organic pyroelectric material has a pyroelectric coefficient of 10 μ C.m or more ^-2 ·K ^-1 (ii) a The inorganic pyroelectric material has a pyroelectric coefficient of 30 [ mu ] C.m or more ^-2 ·K ^-1 。

8. The microfluidic chip of claim 7, wherein the first chip channel layer further comprises a photo-thermal material, or the photo-acoustic response layer further comprises a photo-thermal material; the photothermal conversion rate of the photothermal material is 0.1-99.99%.

9. The microfluidic chip of claim 8, wherein the photothermal material comprises one or more of a metallic photothermal nanomaterial, an inorganic non-metallic photothermal nanomaterial, and a high molecular polymer photothermal material.

10. The microfluidic chip of claim 8 or 9, wherein a mass ratio of the pyroelectric material to the photothermal material is greater than or equal to 1.

11. The microfluidic chip according to any of claims 1 to 10, wherein the first droplet channel is filled with a lubricant, or the second droplet channel is filled with a lubricant; the lubricant comprises vegetable oil, glycol, polyethylene glycol, perfluoropolyether, mineral oil, glycerol, paraffin, N-dodecane, N-dodecene, hexadecene, long-chain lubricant, polyurethane, acrylic polyurethane, fluorine oil, vegetable seed oil, N-decanol, motor lubricant, kerosene, oleic acid, methyl oleate, ethyl oleate, fatty acid amide, stearic acid, stearamide, N-ethylene bis stearamide, oleamide, butyl stearate, glycerol trihydroxystearate, polyester, synthetic ester, carboxylic acid, silicate ester, phosphate ester, synthetic hydrocarbon oil, ferrofluid, thermotropic liquid crystal, ionic liquid, iodoacetic acid, mannitol, eicosapentaenoic acid, algin, alginic acid, mucopolysaccharide, hyaluronic acid, collagen, elastin, allantoin, glucuronic acid, glycolic acid, collagen, mushroom liquid, emodin, and the like, One or more of kelp mucilage, snail mucilage and silicone oil.

12. The microfluidic chip according to any of claims 1 to 11, wherein the material of the chip channel layer comprises inorganic glass, transparent ceramic, transparent wood, organic glass, polyvinyl chloride, polystyrene, polycarbonate, polyethersulfone, polypropylene, polyamide, polyurethane, polyimide, polyethylene terephthalate-1, 4-cyclohexanedimethanol, styrene-acrylonitrile copolymer, styrene-methyl methacrylate copolymer, acrylonitrile-butadiene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, diallyl diglycol carbonate polymer, polymethyl-1-pentene, polytetrafluoroethylene, polyvinylidene fluoride, transparent resin, epoxy resin, polyethylene terephthalate, polyvinyl chloride, polyethylene terephthalate, polyethylene glycol, polyethylene terephthalate, and the like, One or more of phenolic resin, unsaturated polyester resin, cellulose acetate, cellulose nitrate and ethylene-vinyl acetate copolymer.

13. A method of manipulating droplets, comprising: providing a light source and the microfluidic chip as claimed in any one of claims 1 to 12, wherein a droplet channel of the microfluidic chip contains a droplet, an illumination site is formed in the droplet channel by using the light source, and the droplet moves to the illumination site;

or the manipulation method of the droplets comprises: providing a sound source and the microfluidic chip of any one of claims 1 to 12, wherein a droplet channel of the microfluidic chip contains a droplet, and a sound stimulation site is formed in the droplet channel by the sound source, and the droplet moves to the sound stimulation site.

14. The microfluidic chip according to claim 13, wherein the droplet comprises any one of a water droplet, an organic droplet, an inorganic solution droplet, a micro-nano particle suspension droplet, and a biological tissue fluid droplet.

15. Use of the microfluidic chip according to any of claims 1 to 12 in microfluidic chip control systems, biological assays and chemical assays.