CN116764705A - Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof - Google Patents

Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof Download PDF

Info

Publication number
CN116764705A
CN116764705A CN202310784843.4A CN202310784843A CN116764705A CN 116764705 A CN116764705 A CN 116764705A CN 202310784843 A CN202310784843 A CN 202310784843A CN 116764705 A CN116764705 A CN 116764705A
Authority
CN
China
Prior art keywords
layer
polar plate
micro
photoconductive
photoelectric
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202310784843.4A
Other languages
Chinese (zh)
Inventor
张帅龙
李恭
徐冰睿
符荣鑫
李航
李凤刚
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Institute of Technology BIT
Original Assignee
Beijing Institute of Technology BIT
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beijing Institute of Technology BIT filed Critical Beijing Institute of Technology BIT
Priority to CN202310784843.4A priority Critical patent/CN116764705A/en
Publication of CN116764705A publication Critical patent/CN116764705A/en
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/502707—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by the manufacture of the container or its components
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/50273—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by the means or forces applied to move the fluids
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/502761—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads, for physically stretching molecules
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/502769—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by multiphase flow arrangements
    • B01L3/502784—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by multiphase flow arrangements specially adapted for droplet or plug flow, e.g. digital microfluidics
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2400/00—Moving or stopping fluids
    • B01L2400/04—Moving fluids with specific forces or mechanical means
    • B01L2400/0403—Moving fluids with specific forces or mechanical means specific forces
    • B01L2400/0415—Moving fluids with specific forces or mechanical means specific forces electrical forces, e.g. electrokinetic
    • B01L2400/0424—Dielectrophoretic forces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L2400/00—Moving or stopping fluids
    • B01L2400/04—Moving fluids with specific forces or mechanical means
    • B01L2400/0403—Moving fluids with specific forces or mechanical means specific forces
    • B01L2400/0415—Moving fluids with specific forces or mechanical means specific forces electrical forces, e.g. electrokinetic
    • B01L2400/0427—Electrowetting

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Hematology (AREA)
  • Clinical Laboratory Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Micromachines (AREA)

Abstract

The invention discloses a novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and a manufacturing method thereof. The invention provides digital micro-fluidic chips with two structures: the micro flow channel driven by the micro pump is connected with the photoelectric tweezers functional area and the digital micro-fluidic functional area, holes are respectively formed in the upper polar plate of the photoelectric tweezers area and the upper polar plate of the digital micro-fluidic area, and micro liquid drops are transferred in the two functional areas by the micro flow channel and the micro pump; one is to divide a specific area of the digital microfluidic chip into a functional area of the photoelectric tweezers, and shield the area when the dielectric layer is grown. The digital microfluidic chip integrates the advantages of precise and high-flux parallel operation of the micro-object by the photoelectric tweezers technology and the high-flux parallel operation of the micro-droplet by the digital microfluidic technology, and solves the problems that the micro-operation technologies such as the photoelectric tweezers and the like cannot control the liquid environment where the micro-object is located and the precise operation of the micro-substance in the droplet is difficult to realize by the conventional digital microfluidic technology.

Description

Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof
Technical Field
The invention relates to a novel digital microfluidic chip capable of performing operations such as cell sorting and particle capturing and a manufacturing method thereof, belonging to the crossing field of micro-nano operation technology and digital microfluidic technology.
Background
Digital microfluidic technology (DMF), i.e. micro-droplet technology, mainly utilizes dielectric wetting effect to control micro-droplets, and can drive a plurality of micro-droplets in a digitized and arrayed manner on a chip. At present, digital microfluidic chips can realize single-cell-level microfluidic, but the cost of the chips is high, and the chips are difficult to popularize. Therefore, in most digital microfluidic application scenarios, the digital microfluidic chip only operates on the liquid drops, and it is difficult to achieve fine operations of single cells, particles, and the like.
The optical tweezers technology (OET) is an optical manipulation micro-nano operation technology, and mainly utilizes the photo-dielectrophoresis effect to perform micro-nano scale operation on micro-objects (such as cells, substance particles, micro-nano robots and the like). Because of the advantages of precision, high efficiency, high throughput, graphical operation and the like, the technology can perform various cell operations such as cell sorting, cell directional movement, cell fusion, cell lysis and the like; the method can also be used for carrying out various operations of tiny objects, such as capturing tiny particles, patterning and arranging tiny particles, assembling a microcircuit and the like; meanwhile, the photoelectric tweezers technology and the micro-nano robot with a specific structure are combined to realize the specific operation of the micro-nano robot based on the driving of the photoelectric tweezers.
The common photoelectric tweezers chip consists of an upper polar plate, a lower polar plate and double-sided adhesive tape for connecting the upper polar plate and the lower polar plate. The upper electrode plate of the photoelectric tweezers is required to have good light transmittance and good conductivity on the lower surface, and most researchers currently select ITO (indium tin oxide) glass as the upper electrode plate of the photoelectric tweezers chip. The lower electrode plate of the photoelectric tweezer chip needs to grow a thinner photoelectric guide layer on the ITO glass. When the cell operation is performed by using the optical tweezers technology, the method is generally combined with a continuous microfluidic technology, holes are formed in an on-chip polar plate, and injection and collection of samples are realized by matching the polar plate with a micropump. In general, only one external condition can be tested in one operation, while the photoelectric tweezers can realize high-flux parallel control on micro operation, a series of controlled variable tests for complex external conditions cannot be realized on one chip, and when the external conditions are changed, the tests need to be carried out again, so that the efficiency is low.
Both the above technologies have good application in the respective fields, however, there are corresponding drawbacks, but if a digital microfluidic chip capable of performing optical tweezers operation on micro substances in micro droplets can be developed, the above problems can be solved to a great extent.
However, these two techniques are difficult to combine simply. Since the manipulation force of the electro-optical tweezers technology is a photo-dielectrophoresis force, illumination is used to change the conductivity of the electro-optical layer, thereby generating a non-uniform electric field and providing the manipulation force. In view of the increased conductivity of the photoconductive layer in the illuminated portion, the applied voltage required for the photoelectromotive chip is typically small, typically not exceeding 25V, in order to prevent the chip from breakdown and failure. The control force of the digital microfluidic technology is dielectric wetting force, charges are enriched through a dielectric layer, and the contact angle of the liquid drop is changed by utilizing attraction of the charges to the liquid drop, so that the liquid drop is promoted to move. Because the operation object is far larger than micro particles controlled by the photoelectric tweezers, the digital microfluidic technology needs larger external voltage to ensure the control of micro liquid drops, and generally needs 90-110V. If the two technologies are simply combined, the chip breaks down at the illumination part due to the increase of the conductivity of the chip at the illumination part, and the chip is disabled; however, if a low driving voltage is used, manipulation of the microdroplet cannot be achieved.
Therefore, developing a digital microfluidic chip that can perform droplet operations and perform high-throughput parallel operations on micro substances in micro droplets, and providing a corresponding control manner for a novel chip are urgent to those skilled in the art. The invention is proposed for this purpose.
Disclosure of Invention
The invention aims to provide a novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and a manufacturing method thereof, so that the operations such as high-flux cell sorting and particle capturing can be realized on one digital micro-fluidic chip, and the problems that the conventional chip is difficult to transfer liquid drops out of an optical tweezers area and the chip is easy to break down due to high requirements on operation voltage are solved.
The invention provides novel digital micro-fluidic chips with two structures.
The structure of the first novel digital microfluidic chip is as follows:
comprises an upper polar plate and a lower polar plate; wherein,,
the upper polar plate and the lower polar plate are matched in a fitting way to form a photoelectric forceps functional area and a digital micro-fluidic functional area, and the photoelectric forceps functional area and the digital micro-fluidic functional area are separated by an isolation structure;
the upper polar plate corresponding to the photoelectric forceps functional area is provided with a liquid inlet, and the photoelectric forceps functional area is communicated with the digital microfluidic functional area;
the upper polar plate comprises a transparent substrate, and a conducting layer and a hydrophobic layer I which are arranged on the substrate;
the lower polar plate comprises a substrate, a patterned electrode, a photoconductive layer, a dielectric layer and a hydrophobic layer II, wherein the patterned electrode, the photoconductive layer, the dielectric layer and the hydrophobic layer II are arranged on the substrate; wherein the photoconductive layer corresponds to the photoelectric tweezers functional area, and the dielectric layer corresponds to the digital microfluidic functional area;
when the micro-fluidic liquid pump is used, the liquid inlet is connected with the micro-pump to provide driving force for liquid flow, and the photoelectric forceps functional area is connected with the digital micro-fluidic functional area through a micro-channel guide pipe.
Preferably, the material of the conductive layer may be transparent conductive materials such as indium tin oxide transparent conductive film, carbon nanotube transparent conductive film, graphene transparent conductive film, etc.;
the thickness of the conductive layer may be 20nm to 200nm.
Preferably, the patterned electrode may be made of transparent conductive materials such as indium tin oxide transparent conductive film, carbon nanotube transparent conductive film, graphene transparent conductive film, etc.;
the hydrophobic layer I and the hydrophobic layer II can be made of materials with good hydrophobicity such as Teflon, cytop and PFC;
the thickness of the hydrophobic layer I and the hydrophobic layer II can be 10 nm-50 nm;
the substrate can be made of transparent materials such as glass, acrylic plates and the like;
preferably, the photoconductive layer may be made of hydrogenated amorphous silicon, silicon-based phototriode, organic polymer photoconductive material, etc. with good photoconductive property;
the thickness of the photoconductive layer can be 50 nm-5000 nm;
the dielectric layer can be made of silicon nitride, silicon dioxide or parylene C;
the thickness of the dielectric layer may be 0.1um to 50um.
Preferably, the isolation structure may be a non-conductive adhesive material such as waterproof tape, PDMS, photoresist, etc.
The microfluidic chip of the invention can be manufactured according to the following method:
s1, manufacturing the upper polar plate
Sequentially preparing the conducting layer and the hydrophobic layer I on the substrate, and then punching to form the liquid inlet and a through hole for communicating the photoelectric tweezers functional area and the digital microfluidic functional area;
s2, manufacturing the lower polar plate
Preparing the patterned electrode on the substrate, preparing the photoconductive layer and the dielectric layer on the patterned electrode, and preparing the hydrophobic layer II on the photoconductive layer and the dielectric layer;
and S3, fitting the upper polar plate and the lower polar plate, and separating the photoelectric tweezers functional area and the digital microfluidic functional area by adopting the isolation structure.
The functional layers can be prepared according to the existing method, for example, the conductive layer can be prepared by adopting a PECVD method, the patterned electrode can be prepared by adopting a Lift-Off method, the dielectric layer can be prepared by adopting a PECVD method, the photoconductive layer can be prepared by adopting a PECVD method, and the hydrophobic layer can be prepared by adopting a spin-on heating method.
When the digital micro-fluidic chip is applied, the method can be carried out according to the following steps:
1) Injecting micro liquid drops to be operated into the functional areas of the photoelectric tweezers by adopting a micro pump;
2) Changing the conductivity of the photoconductive layer by illumination to generate a non-uniform electric field;
3) The dielectrophoresis force is utilized to perform high-flux parallel operation such as enrichment, capture and the like on the particles to be operated, and the particles can also be combined with a micropump to realize the screening of the particles;
4) After the operation of the photoelectric tweezers is finished, transferring the liquid drops after the operation into the digital microfluidic functional area by adopting a micropump;
5) By applying voltage to the driving electrode, dielectric wetting force is generated on the liquid drops, the liquid drops are attracted to move along the driving electrode, and high-flux parallel operation such as liquid separation, uniform mixing and the like is realized on the micro liquid drops.
The structure of the second novel digital microfluidic chip is as follows:
comprises an upper polar plate and a lower polar plate; the upper polar plate and the lower polar plate are matched in a fitting way to form a digital microfluidic function area; wherein:
a plurality of photoelectric tweezers function areas formed inside the digital microfluidic function area;
the upper polar plate comprises a substrate, a conductive layer, a photoconductive layer and a hydrophobic layer A, wherein the conductive layer, the photoconductive layer and the hydrophobic layer A are arranged on the substrate, the photoconductive layer A is arranged on the conductive layer and the photoconductive layer, and the photoconductive layer is arranged on the conductive layer;
the lower polar plate comprises a substrate, a patterned electrode, a dielectric layer and a hydrophobic layer B, wherein the patterned electrode, the dielectric layer and the hydrophobic layer B are arranged on the substrate, the hydrophobic layer B is arranged on the dielectric layer and the patterned electrode, the dielectric layer is arranged on the patterned electrode of the digital microfluidic functional region, the patterned electrode with the middle part exposed corresponds to the photoconductive layer, and the region between the patterned electrode and the photoconductive layer forms the photoelectric tweezer functional region.
Wherein, the material and thickness of each functional layer are not substantially different from those of the first digital micro-fluidic chip.
The microfluidic chip of the invention can be manufactured according to the following method:
s I, manufacturing of the upper polar plate
Preparing the conductive layer on the substrate, preparing the patterned photoconductive layer array on the conductive layer, and preparing the hydrophobic layer A on the conductive layer and the photoconductive layer;
s II, manufacturing the lower polar plate
Preparing the patterned electrode on the substrate, preparing the dielectric layer on the patterned electrode of the digital microfluidic function region, and preparing the hydrophobic layer B on the dielectric layer and the patterned electrode with the middle part exposed;
and S III, fitting the upper polar plate and the lower polar plate, wherein the region between the photoconductive layer and the patterned electrode is the photoelectric forceps functional region, and the rest regions are the digital microfluidic functional regions.
The functional layers can be prepared according to the existing method, for example, the conductive layer can be prepared by adopting a PECVD method, the patterned electrode can be prepared by adopting a Lift-Off method, the dielectric layer can be prepared by adopting a Lift-Off method, the patterned photoconductive layer array can be prepared by adopting a Lift-Off method, and the hydrophobic layer can be prepared by adopting a spin-on heating method.
The digital microfluidic chip with the second structure needs to consider the connection between the photoelectric tweezers functional area and the digital microfluidic functional area, namely, the liquid drops are controlled to reach the photoelectric tweezers area, and the next liquid drop operation is carried out by utilizing dielectric wetting after the photoelectric tweezers are controlled. The area of the photoelectric tweezers functional area is required to be smaller than the electrode area of the digital microfluidic functional area, namely, a photoelectric tweezers control area is planned at the center of the digital microfluidic electrode, so that the purpose that liquid drops freely enter and exit the photoelectric tweezers area is realized.
According to the invention, the hydrophobic layer is arranged in the functional area of the photoelectric tweezers, so that the problems that the traditional microfluidic chip is difficult to transfer liquid drops out of the functional area of the photoelectric tweezers and the chip is easy to break down due to high requirements on operation voltage are solved: when the function area of the photoelectric tweezers is not provided with a hydrophobic layer, liquid drops are easily attracted by the function area of the photoelectric tweezers and are difficult to control by dielectric wetting force, and the bias voltage of a digital microfluidic driving electrode needs to be increased, so that the chip is extremely easy to break down and discard; secondly, because the photoconductive layer is thinner, the movement of the liquid drops is not influenced by the small-range protrusions, the photoconductive layer is not used in the digital microfluidic region, the requirement for driving voltage is increased by the redundant photoconductive layer instead, and one layer of photoconductive layer is not required to be paved in the whole digital microfluidic region.
When the digital microfluidic chip is applied, the method can be carried out according to the following steps:
1) Adding liquid drops to be operated into the digital micro-fluidic chip through a sample injection hole or a liquid storage electrode;
2) Applying voltage to a driving electrode on a programmable path, wherein the generated dielectric wetting force can attract liquid drops to move along the programmable path, so that operations such as mixing and liquid separation of the liquid drops are realized;
3) If the operation of the photoelectric tweezers is needed, applying voltage to the photoelectric tweezers electrode and the surrounding transition electrode, and attracting the liquid drops to be operated to enter the photoelectric tweezers functional area by utilizing dielectric wetting force;
4) Applying illumination to the photoconductive layer to generate a nonuniform electric field, and realizing high-flux parallel operation such as enrichment, capture and the like on target particles in liquid drops by utilizing dielectrophoresis force;
5) After the operation is completed, the transition electrode and the driving electrode are activated, and the movement of the micro-droplet is realized by utilizing the dielectric wetting force. If the cell culture solution is to be updated in the photoelectric forceps region, cells in the micro-droplets can be fixed by using dielectrophoresis force of the photoelectric forceps, and the fresh culture solution is controlled to enter the photoelectric forceps operating region by using dielectric wetting force and the old culture solution is controlled to leave the photoelectric forceps operating region, so that the operations such as updating the cell culture solution on the sheet are realized.
The photoelectric tweezers technology can realize the fine operation of single cells and particle levels, can control a plurality of targets to operate in parallel, has the advantages of accuracy and high flux of particle size, and the digital microfluidic technology can realize the high flux parallel operation of a plurality of liquid drops on the micro liquid drop level. For example, the novel chip can be used for carrying out drug resistance experiments on cells, the digital microfluidic technology can realize transportation of drugs and nutrient substances, multiple groups of experiments can be carried out simultaneously by utilizing the advantage of high flux parallelism of the novel chip, and the photoelectric tweezers technology can enrich cells in single liquid drops so as to separate the cells from metabolic waste liquid by utilizing the liquid separation function of the digital microfluidic technology.
Aiming at the problem that the voltage required by digital micro-fluidic is extremely easy to break through the photoelectric guide layer of the photoelectric tweezer chip, the invention creatively develops two digital micro-fluidic chips capable of performing photoelectric tweezer operation. On the basis, the invention integrates the advantages of accurate and high-flux parallel operation of the optical tweezers technology on the micro objects and the high-flux parallel operation of the digital microfluidic technology on the micro liquid drops, and solves the problems that the micro operation technologies such as the optical tweezers and the like cannot control the liquid environment where the micro objects are located and the accurate operation of the micro substances in the liquid drops is difficult to realize by the conventional digital microfluidic technology.
Drawings
Fig. 1 is a schematic structural diagram of a first digital microfluidic chip according to the present invention.
Fig. 2 is a schematic structural diagram of a second digital microfluidic chip according to the present invention.
Fig. 3 is a schematic diagram of an electrode arrangement in the digital microfluidic chip shown in fig. 2.
The figures are marked as follows:
1 micropump, 2 conducting layer, 3,5 hydrophobic layer, 4 waterproof tape, 6 photoelectric conducting layer, 7 patterned electrode, 7-1 digital micro-fluidic functional area patterned electrode, 7-2 photoelectric tweezers functional area patterned electrode, 8 conduit, 9, 11 substrate, 10 dielectric layer, 12 micro-droplet, 13 micro-substance, 14 digital micro-fluidic driving electrode, 15 functional interval transition electrode, 16 photoelectric tweezers electrode.
Detailed Description
The present invention will be further described with reference to the accompanying drawings, but the present invention is not limited to the following examples.
Example 1,
As shown in fig. 1, a schematic structural diagram of a digital microfluidic chip with a first structure provided by the invention is that a micro-channel driven by a micro-pump is used to connect a photoelectric tweezers functional area and a digital microfluidic functional area, holes are respectively formed in an upper polar plate of the photoelectric tweezers area and an upper polar plate of the digital microfluidic area, and micro-liquid drops are transferred in the two functional areas by the micro-channel and the micro-pump.
As shown in fig. 1, the digital microfluidic chip with the first structure provided by the invention has the following structure:
comprises a transparent upper polar plate and a transparent lower polar plate. Wherein, the upper polar plate and the lower polar plate are fit to form a photoelectric forceps functional area and a digital micro-fluidic functional area, and the photoelectric forceps functional area and the digital micro-fluidic functional area are separated by a waterproof adhesive tape 4.
As shown in fig. 1, a liquid inlet is arranged on the corresponding upper polar plate of the photoelectric forceps functional area and is connected with a micropump 1, the photoelectric forceps functional area is communicated with the digital microfluidic functional area through a conduit 8, and the micropump 1 provides power for transferring liquid drops in the photoelectric forceps functional area and the digital microfluidic functional area.
As shown in fig. 1, the upper electrode plate comprises a transparent substrate 9, a transparent conductive layer 2 and a hydrophobic layer 3 arranged on the substrate 9, and the lower electrode plate comprises a substrate 11, a patterned electrode 7 arranged on the substrate, a photoconductive layer 6, a dielectric layer 10 and a hydrophobic layer 5; wherein the photoconductive layer 6 corresponds to the functional region of the electro-optical tweezers and the dielectric layer 10 corresponds to the functional region of the digital micro-fluidic.
In fig. 1, reference numeral 12 denotes a micro-droplet which can be operated in parallel with high throughput by a digital microfluidic chip, and reference numeral 13 denotes a micro-substance such as a cell, a substance particle, etc. in the micro-droplet environment which can be specifically operated in parallel with high throughput by a pair of electro-optical tweezers.
In this embodiment, the material of the conductive layer 2 may be a transparent conductive material, such as Indium Tin Oxide (ITO), which is grounded in the circuit and has a thickness of 20 nm-200 nm; the material of the hydrophobic layers 3 and 5 can be Teflon, cytop, PFC and other materials, and the thickness can be 10 nm-50 nm; the photoconductive layer 6 can be made of hydrogenated amorphous silicon, silicon-based phototriode, organic polymer photoconductive material, and the like, and the thickness can be 50 nm-5000 nm; the patterned electrode 7 may be made of ITO, wherein the electrode in the functional region of the electro-optical tweezers is connected to a low voltage, and the electrode in the functional region of the digital microfluidic is connected to a high voltage. The substrate 9 may be made of glass, acrylic plate, etc.; the dielectric layer 10 may be silicon nitride with a thickness of 0.1um to 50um, and the substrate 11 may be glass, acrylic plate, silicon plate, etc., and if an inverted microscope is used for observation, a transparent material is required.
The manufacturing method of the digital micro-fluidic chip provided by the embodiment is as follows:
1. the manufacturing method of the upper polar plate comprises the following steps:
1) A conductive layer 2 is grown on a substrate 9. A transparent conductive film is prepared on the substrate 9 by using a PECVD method, namely a conductive layer 2.
2) A hydrophobic layer 3 is prepared on the conductive layer 2. And (3) dropwise adding a hydrophobic material solution on the conductive layer 2, spin-coating by using a spin coater to ensure that the hydrophobic layer is uniform and smooth, and then placing the conductive layer into an oven for heating and annealing to obtain the hydrophobic layer 3.
3) And punching according to the parameters of the microfluidic pump and the guide pipe.
2. The manufacturing method of the lower polar plate comprises the following steps:
1) Patterned electrode 7 was fabricated on substrate 11 using a Lift-Off process. Photoresist is spin-coated on the substrate 11, and a corresponding pattern is photo-etched according to the electrode pattern. On the basis, a layer of transparent conductive material is grown by a PECVD method, and the surplus photoresist and the redundant conductive material attached to the surface of the photoresist are washed away to obtain the patterned electrode 7.
2) The photo-conductive layer 6 is grown in the region of the photo-tweezers and the dielectric layer 10 is grown in the digital microfluidic region, respectively, using a Lift-Off process.
3) A hydrophobic layer 5 was prepared using spin-on heating. And (3) dropwise adding a hydrophobic material solution on the photoconductive layer 6 and the dielectric layer 10, spin-coating by using a spin coater to ensure that the hydrophobic layer is uniform and smooth, and then placing the materials into an oven for heating and annealing to obtain the hydrophobic layer 5.
The use process of the digital microfluidic chip of the embodiment is as follows:
1. injecting micro liquid drops to be operated into the functional areas of the photoelectric tweezers by using a micro pump;
2. using the change of the conductivity of the photoconductive layer 6 by illumination, a non-uniform electric field is generated;
3. the dielectrophoresis force is utilized to perform high-flux parallel operation such as enrichment, capture and the like on the particles to be operated, and the particles can also be combined with the micropump 1 to realize the screening of the particles;
4. after the operation of the photoelectric tweezers is finished, transferring the liquid drops after the operation into a digital microfluidic function area by using a micropump 1;
5. by applying voltage to the driving electrode, dielectric wetting force is generated on the liquid drops, the liquid drops are attracted to move along the driving electrode, and high-flux parallel operation such as liquid separation, uniform mixing and the like is realized on the micro liquid drops.
The digital microfluidic chip of the embodiment can realize the operations of accurately, specifically and high-flux sorting, screening, capturing and the like on cell-level operation objects such as sea-pulling cells, circulating tumor cells and the like and exosomes of various target cells.
EXAMPLE 2,
As shown in fig. 2, a schematic structural diagram of a digital microfluidic chip with a second structure provided by the present invention divides a specific area of the digital microfluidic chip into functional areas of the electro-optical tweezers, and shields the specific area when the dielectric layer is grown. The electrode of the photoelectric forceps functional area is low voltage (about 20V) to prevent breakdown, and the electrode of the digital microfluidic functional area is high voltage (about 100V) to perform operations such as liquid drop movement, liquid separation, uniform mixing and the like.
As shown in fig. 2, the digital microfluidic chip with the second structure provided by the invention has the following structure:
the device comprises an upper polar plate and a lower polar plate, wherein the upper polar plate and the lower polar plate are matched in a fitting way to form a digital microfluidic function area; wherein: a plurality of photoelectric tweezers functional areas (only one photoelectric tweezers functional area is shown in the figure) are formed inside the digital microfluidic functional area.
As shown in fig. 2, the upper polar plate comprises a transparent substrate 9, a conductive layer 2 arranged on the substrate 9, a photoconductive layer 6 and a hydrophobic layer 3, wherein the hydrophobic layer 3 is arranged on the conductive layer 2 and the photoconductive layer 6, and the photoconductive layer 6 in one photoelectric tweezers functional area is arranged in the middle of the conductive layer 2.
As shown in fig. 2, the lower electrode plate comprises a substrate 11, a patterned electrode, a dielectric layer 10 and a hydrophobic layer 5, wherein the patterned electrode 7-1 of the digital microfluidic function region at two ends modifies the dielectric layer 10 and then covers the hydrophobic layer 5, the patterned electrode 7-2 of the photoelectric tweezers function region exposed in the middle directly covers the hydrophobic layer 5, the patterned electrode 7-2 of the electric tweezers function region corresponds to the photoelectric guide layer 6, and the region between the patterned electrode 7-2 and the photoelectric tweezers function region forms the photoelectric tweezers function region.
In this embodiment, the material and thickness of each functional layer are not substantially different from those of the first digital microfluidic chip.
In fig. 2, reference numeral 12 denotes a micro-droplet which can be operated in parallel with high throughput by a digital microfluidic chip, and reference numeral 13 denotes a micro-substance such as a cell, a substance particle, etc. in the micro-droplet environment which can be specifically operated in parallel with high throughput by a pair of electro-optical tweezers.
Fig. 3 is an electrode arrangement example of a patterned electrode, 14 represents a digital microfluidic driving electrode for controlling micro-droplets to perform high-flux parallel movement, 15 represents a functional interval transition electrode, so that the droplets can be conveniently transferred between a photoelectric tweezers functional area and a digital microfluidic functional area; the micro-liquid drop separation and other operations can be realized by combining the micro-liquid drop detection device with the digital micro-fluidic driving electrode 14, and the electrode 16 represents an electric tweezers electrode, and an electric field can be provided for the functional area of the electric tweezers by combining the electrode plate with a corresponding polar plate.
The manufacturing method of the digital micro-fluidic chip provided by the embodiment is as follows:
manufacturing method of I and upper polar plate
1) Preparing a conductive layer 2 on a substrate 9; a transparent conductive film is prepared on the substrate 9 by using a PECVD method, namely a conductive layer 2.
2) A patterned photoconductive layer 6 is prepared on the conductive layer 2 using a Lift-Off process; firstly, photoresist is coated on the conductive layer 2 in a spinning way, and corresponding patterns are formed according to the photoetching plate of the photoelectric guiding layer in a photoetching way. And then growing a layer of photoconductive film by using a PECVD method, and washing off the residual photoresist and the redundant photoconductive film on the residual photoresist to obtain the patterned photoconductive layer 6.
3) Preparing a hydrophobic layer 3 on the conductive layer 2 and the photoconductive layer 6; and (3) dropwise adding a hydrophobic material solution on the conductive layer 2 and the photoconductive layer 6, spin-coating by using a spin coater to ensure that the hydrophobic layer is uniform and smooth, and then heating in an oven and annealing to obtain the hydrophobic layer 3.
II, manufacturing method of lower polar plate
1) Growing a patterned conductive layer 2 on a substrate 11 using a Lift-Off process; first, photoresist is spin-coated on a substrate 11, and corresponding patterns are photo-etched according to the photo-etching plate of the electrode array. And then growing a layer of conductive film by using a PECVD method, and washing off the residual photoresist and the redundant conductive film on the residual photoresist to obtain the patterned conductive layer 2.
2) And growing a sacrificial layer in the functional area of the photoelectric tweezers by using a PECVD process, wherein the sacrificial layer is used for preventing the dielectric layer from growing in the functional area of the photoelectric tweezers.
3) A layer of dielectric 10, such as silicon nitride, is grown using a PECVD process.
4) And removing the sacrificial layer, wherein a dielectric layer is covered on the digital microfluidic region, and the photoelectric tweezers region is a bare drain electrode.
5) A hydrophobic layer 5 is prepared by spin-coating heating, and a dielectric layer 10 and a conductive layer 2 of the photoelectric tweezers region are covered.
III, the upper polar plate is matched with the lower polar plate in a fitting way, the region between the photoconductive layer 6 and the patterned electrode 7-2 of the photoelectric tweezer functional region is the photoelectric tweezer functional region, and the rest regions are digital microfluidic functional regions.
The use process of the digital microfluidic chip of the embodiment is as follows:
1. adding liquid drops to be operated into the digital microfluidic chip through a sample injection hole or a liquid storage electrode;
2. applying voltage to a driving electrode on a programmable path, wherein the generated dielectric wetting force can attract liquid drops to move along the programmable path, so that operations such as mixing and liquid separation of the liquid drops are realized;
3. if the operation of the photoelectric tweezers is needed, applying voltage to the photoelectric tweezers electrode and the surrounding transition electrode, and attracting the liquid drops to be operated to enter the photoelectric tweezers functional area by utilizing dielectric wetting force;
4. applying illumination to the photoconductive layer to generate a nonuniform electric field, and realizing high-flux parallel operation such as enrichment, capture and the like on target particles in the liquid drops by utilizing dielectrophoresis force;
5. after the operation is completed, the transition electrode and the driving electrode are activated, and the movement of the micro-droplet is realized by utilizing the dielectric wetting force. If the cell culture solution is to be updated in the photoelectric forceps region, cells in the micro-droplets can be fixed by using dielectrophoresis force of the photoelectric forceps, and the fresh culture solution is controlled to enter the photoelectric forceps operating region by using dielectric wetting force and the old culture solution is controlled to leave the photoelectric forceps operating region, so that the operations such as updating the cell culture solution on the sheet are realized.
The digital microfluidic chip of the embodiment can realize the operations of accurately, specifically and high-flux sorting, screening, capturing and the like on cell-level operation objects such as sea-pulling cells, circulating tumor cells and the like and exosomes of various target cells.
The present disclosure is based on the development of digital microfluidic chips that can be operated with optical tweezers, and the processing of the chips includes, but is not limited to, the cases mentioned herein. The chip based on the invention and improved on the basis of the invention is simply modified by a person skilled in the art on the basis of the reference to the invention, and is within the protection scope of the invention.

Claims (10)

1. A micro-fluidic chip capable of operating an optical tweezers comprises an upper polar plate and a lower polar plate; the method is characterized in that:
the upper polar plate and the lower polar plate are matched in a fitting way to form a photoelectric forceps functional area and a digital micro-fluidic functional area, and the photoelectric forceps functional area and the digital micro-fluidic functional area are separated by an isolation structure;
the upper polar plate corresponding to the photoelectric forceps functional area is provided with a liquid inlet, and the photoelectric forceps functional area is communicated with the digital microfluidic functional area;
the upper polar plate comprises a substrate, and a conductive layer and a hydrophobic layer I which are arranged on the substrate;
the lower polar plate comprises a substrate, a patterned electrode, a photoconductive layer, a dielectric layer and a hydrophobic layer II, wherein the patterned electrode, the photoconductive layer, the dielectric layer and the hydrophobic layer II are arranged on the substrate; wherein the photoconductive layer corresponds to the photoelectric tweezers functional area, and the dielectric layer corresponds to the digital microfluidic functional area.
2. The microfluidic chip of claim 1, wherein: the material of the conductive layer is transparent conductive material, such as: indium tin oxide transparent conductive film, carbon nanotube transparent conductive film, graphene transparent conductive film;
the thickness of the conductive layer is 20 nm-200 nm.
3. The microfluidic chip according to claim 1 or 2, wherein: the patterned electrode is made of transparent conductive material, such as: indium tin oxide transparent conductive film, carbon nanotube transparent conductive film, graphene transparent conductive film;
the material of the hydrophobic layer I and the hydrophobic layer II is a hydrophobic material, such as: teflon, cytop, PFC;
the thickness of the hydrophobic layer I and the hydrophobic layer II is 10 nm-50 nm;
the substrate is made of transparent materials, such as: glass and acrylic plate.
4. A microfluidic chip according to any one of claims 1-3, wherein: the photoconductive layer is made of materials with good photoconductive properties, such as: hydrogenated amorphous silicon, a semiconductor phototransistor, an organic high molecular photoconductive material, an inorganic semiconductor photoconductive material, and an inorganic photoconductive material;
the thickness of the photoconductive layer is 50 nm-5000 nm;
the dielectric layer is made of a material with good dielectric properties, such as: silicon nitride, silicon dioxide, parylene C, inorganic semiconductor dielectric materials, organic polymer dielectric materials;
the thickness of the dielectric layer is 0.1 um-50 um.
5. The microfluidic chip according to any one of claims 1-4, wherein: the isolation structure is an adhesive waterproof material, such as: waterproof adhesive tape, PDMS, photoresist.
6. The method for manufacturing a microfluidic chip according to any one of claims 1 to 5, comprising the steps of:
s1, manufacturing the upper polar plate
Sequentially preparing the conducting layer and the hydrophobic layer I on the substrate, and then punching to form the liquid inlet and a through hole for communicating the photoelectric tweezers functional area and the digital microfluidic functional area;
s2, manufacturing the lower polar plate
Preparing the patterned electrode on the substrate, preparing the photoconductive layer and the dielectric layer on the patterned electrode, and preparing the hydrophobic layer II on the photoconductive layer and the dielectric layer;
and S3, fitting the upper polar plate and the lower polar plate, and separating the photoelectric tweezers functional area and the digital microfluidic functional area by adopting the isolation structure.
7. A micro-fluidic chip capable of operating an optical tweezers comprises an upper polar plate and a lower polar plate; the upper polar plate and the lower polar plate are matched in a fitting way to form a digital microfluidic function area; the method is characterized in that:
a plurality of photoelectric tweezers function areas are formed inside the digital microfluidic function area;
the upper polar plate comprises a substrate, a conductive layer, a photoconductive layer and a hydrophobic layer A, wherein the conductive layer, the photoconductive layer and the hydrophobic layer A are arranged on the substrate, the photoconductive layer A is arranged on the conductive layer and the photoconductive layer, and the photoconductive layer is arranged on the conductive layer;
the lower polar plate comprises a substrate, a patterned electrode, a dielectric layer and a hydrophobic layer B, wherein the patterned electrode, the dielectric layer and the hydrophobic layer B are arranged on the substrate, the hydrophobic layer B is arranged on the dielectric layer and the patterned electrode, the dielectric layer is arranged on the patterned electrode of the digital microfluidic functional region, the patterned electrode with the middle part exposed corresponds to the photoconductive layer, and the region between the patterned electrode and the photoconductive layer forms the photoelectric tweezer functional region.
8. The microfluidic chip of claim 7, wherein: the material of the conductive layer is transparent conductive material, such as: indium tin oxide transparent conductive film, carbon nanotube transparent conductive film, graphene transparent conductive film;
the thickness of the conductive layer is 20 nm-200 nm;
the patterned electrode is made of transparent conductive material, such as: indium tin oxide transparent conductive film, carbon nanotube transparent conductive film, graphene transparent conductive film;
the materials of the hydrophobic layer a and the hydrophobic layer B are hydrophobic materials, such as: teflon, cytop, PFC;
the thickness of the hydrophobic layer A and the thickness of the hydrophobic layer B are 10 nm-50 nm;
the substrate is made of transparent materials such as: glass and acrylic plate.
9. The microfluidic chip according to claim 7 or 8, wherein: the photoconductive layer is made of materials with good photoconductive properties, such as: hydrogenated amorphous silicon, silicon-based phototriodes, organic high-molecular photoconductive materials, inorganic semiconductor photoconductive materials and inorganic photoconductive materials;
the thickness of the photoconductive layer is 50 nm-5000 nm;
the dielectric layer is made of a material with good dielectric properties, such as: silicon nitride, silicon dioxide, parylene C, inorganic semiconductor dielectric materials, organic polymer dielectric materials;
the thickness of the dielectric layer is 0.1 um-50 um.
10. The method for manufacturing the microfluidic chip according to claim 8 or 9, comprising the steps of:
s I, manufacturing of the upper polar plate
Preparing the conductive layer on the substrate, preparing the photoconductive layer on the conductive layer, and preparing the hydrophobic layer A on the conductive layer and the photoconductive layer;
s II, manufacturing the lower polar plate
Preparing the patterned electrode on the substrate, preparing the dielectric layer on the patterned electrode of the digital microfluidic function region, and preparing the hydrophobic layer B on the dielectric layer and the patterned electrode with the middle part exposed;
and S III, fitting the upper polar plate and the lower polar plate, wherein the region between the photoconductive layer and the patterned electrode is the photoelectric forceps functional region, and the rest regions are the digital microfluidic functional regions.
CN202310784843.4A 2023-06-29 2023-06-29 Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof Pending CN116764705A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310784843.4A CN116764705A (en) 2023-06-29 2023-06-29 Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310784843.4A CN116764705A (en) 2023-06-29 2023-06-29 Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof

Publications (1)

Publication Number Publication Date
CN116764705A true CN116764705A (en) 2023-09-19

Family

ID=88007885

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310784843.4A Pending CN116764705A (en) 2023-06-29 2023-06-29 Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN116764705A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117920372A (en) * 2024-03-18 2024-04-26 微纳动力(北京)科技有限责任公司 Optical tweezers chip and manufacturing method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117920372A (en) * 2024-03-18 2024-04-26 微纳动力(北京)科技有限责任公司 Optical tweezers chip and manufacturing method thereof

Similar Documents

Publication Publication Date Title
JP6826618B2 (en) Electronic control of fluid species
US11123729B2 (en) Directing motion of droplets using differential wetting
KR100991752B1 (en) Apparatus and Method for Microparticle Manipulation Using Single Planar Optoelectronic Device
US11103868B2 (en) Microfluidic chip, biological detection device and method
US20220016631A1 (en) Microdroplet manipulation device
WO2021208872A1 (en) Electrohydrodynamics-based microfluidic chip, micro sample application device and method
CN1645089A (en) Sorting particles
CN1644250A (en) Sorting particles in parallel
CN116764705A (en) Novel digital micro-fluidic chip capable of performing operations such as cell sorting and particle capturing and manufacturing method thereof
CN108169966B (en) Droplet control detection device and droplet control detection method
CN109580506A (en) A kind of fungal detection system and two Methods for Fungi Detection based on digital microfluidic technology
JP2005531409A (en) Apparatus and method for optical driving of microfluidics based on light and electrical wetting
CN107250344B (en) Self-locking photoelectric tweezers and manufacture thereof
Yu et al. Integration of organic opto-electrowetting and poly (ethylene) glycol diacrylate (PEGDA) microfluidics for droplets manipulation
CN104096608A (en) Separated type automatic micron-size particle assembling and sorting device and manufacturing method thereof
EP3656472A1 (en) Cell analyser
CN116899644B (en) Photoelectric micro-fluidic device and system
US20200230605A1 (en) Device for sorting bio-particles using image-manipulated electric force and operating method thereof
Liu et al. Two-dimensional manipulation of droplets on a single-sided continuous optoelectrowetting digital microfluidic chip
KR100921561B1 (en) Apparatus for Optoelectronic Microparticle Manipulation of Integrating Each Electrode
TW201736819A (en) Biological micro-particle capture and retrieval system and method especially for capturing a single target biological micro particle and separating from the liquid specimen
Chen et al. Development of coplanar electro-wetting based microfluidic sorter to select micro-particles in high volume throughput at milliliter amount within twenty minutes
Witte et al. Channel integrated optoelectronic tweezer chip for microfluidic particle manipulation
JP4651715B2 (en) Liquid analyzer
KR20230172547A (en) Method and device for capturing at least one nucleated cell using at least one electrode for a microfluidic device

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination