CN1330151A - Flow-type cell instrument based on microflow control technique - Google Patents

Abstract

A flow cytometer based on micro-flow control technique is a miniature one composed of base, casing, micro-flow control chip, optical detection unit, fluid I/O interface, micro-displacement regulating table, signal processing box, connecting cables and control host. Its optical detection is performed by regulating the relative position.

Description

A kind of flow cytometer based on microflow control technique

What the present invention relates to is a kind of novel flow cytometer based on microflow control technique.Flow cytometer can carry out fast quantitative analysis to the multiple physics and the biological characteristics of biological particles (mainly being cell, microorganism, synthetic microballoon), and to the sorting in addition of specific cells colony.

Flow cytometer has purposes widely in multidisciplinary fields such as current cytobiology, immunology, oncology, hematology, pathology, genetics, Clinical Laboratorys.Passed through half a century from first the cell of flow state being observed so far, flow cytometry is the mobile cell from microscopically visual inspection kapillary, with simple optoelectronic equipment record in addition, develop into today a kind of (per second is measured thousands of cells) fast, the multiparameter measurement of correlation (can not only pair cell colony or the subgroup of composition carry out quantitative analysis, the simultaneously quantitatively DNA or the rna content of cell, enzyme amount activity) and carry out sorting (from cell colony, separate with certain subgroup of purifying so that further to its function, morphology research and cultivate or do other and analyze) height advanced person's technological method.Flow cytometry is responsive and multi-functional detection method to the optical characteristics of microorganism particle.The principle of work of flow cytometer is the suspension that cell preparation to be measured is become individual cells, puts into sample hose behind the specificity fluorescent dyeing, enters flow chamber under the pressure effect of gas.Be full of sheath fluid in the flow chamber, the about bundle cell of sheath fluid is arranged in single-row nozzle ejection by flow chamber, becomes the cell fluid column.The oval focal spot of fluid column and incident laser beam intersects vertically, and joining is a measurement zone.Cell by measurement zone is produced fluorescence by laser excitation.Place optical system (lens, diaphragm, filter disc and detector etc.) in order to collect fluorescent signal at laser beam incident bundle and fluid column vertical direction.Fluorimetric detector is a photomultiplier, in order to collect the fluorescent signal of different wave length.Light scattering detector is a photorectifier, is used for collecting forward scatter light and side scattered light.The principle of cell sorting is: drop forms the signal of the about 30KHZ of frequency, this signal is added in the mechanical vibration that make it to produce different frequency on the piezoquartz, flow chamber is vibration thereupon also, so fluid column fragments into a succession of uniform drop, its formation speed is about for 30,000/second.If the characteristic of cell conforms to the chosen cell characteristics that will carry out sorting, then instrument fills with specified electric charge for when this chosen cell has just formed drop whole fluid column, the drop deflection under the effect of high tension electrostatic field that has electric charge falls into specified container, thereby realizes the collection of pair cell classification.The flow cytometer of traditional commercialization is large-scale, complicated instrument, needs empirical operator and uses.

The proposition of micro-fluidic chip technology is of long duration.Along with the propelling of semiconductor fabrication, the storage capacity of semi-conductor chip is with geometric growth, people to the information processing ability also along with the proposition of parallel processing technique is developed rapidly.The raising that has promoted ability that the unknown is sought is handled in the parallelization of information.Typical example is exactly the Human Genome Project.The large scale sequencing ability is that fulfiling ahead of schedule of the Human Genome Project laid a good foundation.Utilize the magnanimity information of Human genome simultaneously, the scientist of various countries designs the index that biochip comes parallel detection people's various biochemical pathology, and the develop rapidly in this present field has proved the huge market potential and the development prospect of this industry.

With the method for traditional biochemical test with instrument is microminiaturized and the thinking of miniaturization A in the early 1990s.Obtain preliminary realization in the paper of little chemical analysis system of MANZ.The various microminiaturized chemical treatment chip technologies that originate from the semiconductor fine processing technology have appearred subsequently, the electric field chemical treatment chip of NANOGEN company for example, the fluid chip of CALIPER company, the microfluid system of REDWOODMICRO company etc.Hewlett-Packard Corporation and the CALIPER company that is absorbed in the bioinformation processing form the exploitation that JDP is engaged in chip lab.They estimate that the market of chip lab has 1,000,000,000 US dollars in the coming years.Typical patent has US6071394,5632286,5639423,5824204,5890745,6099803,5296114 etc.

The research of performer such as simultaneously relevant micro fluidic plate, micro-fluid pump, microfluidic valve is also carried out.The various little valves that utilize silicon processing technique utilize thermal source, and pressure source, electricity drive silicon fiml, shape memory alloy film and realize that the switching of little valve controls the break-make of microfluid.The pump of microfluid utilizes fluid pressure to drive and realizes.The classification of Micropump is divided into from driving angle: hot driving, Piezoelectric Driving, static driven, electromagnetic drive etc.The flow of pump is by 7.5UL/MIN is to 1200UL/MIN.German scholar is developed micro fluidic plate, and Micropump, little valve, microfluidic channel are integrated, and adopts the thinking convection cell plate that flexibly connects to make up simultaneously and finishes stronger function.

The research of microfluidic channel has obtained many gratifying results.On silicon substrate, utilize methods such as silicon photoetching, burn into reactive ion etching, ion milling successfully to obtain the microchannel of different shape and depth-to-width ratio.Can produce the part that has microfluidic channel in enormous quantities by LIGA technology, little injection molding technology in addition.

The chip material master has glass, silicon chip, quartz, plastics, pcb board etc.Adopt the method for corrosion or injection moulding to go out fluid cavity or fluid slot in the surface working of matrix.Every kind of material is each has something to recommend him.Quartzy insulating property are good, and the UV-light perviousness is strong, are the desirable base materials of electrophoretic analysis.Polymer materials is applicable to cheap batch process.Silicon chip is because IC technology also is applicable to production in enormous quantities, but owing to its semiconductor material, it is infeasible from the use angle of reality to apply high pressure.

The transport process of the little quality in the treating processes of micro-fluid chip, the transport process of low-grade fever amount, stress in electric field, magnetic field, the use, strain, the input of the microfluids such as change of fluid line and reaction chamber surface property, the interface of output are difficult problems that troubles the investigator always.Present typical method is used the built-in tubule of fluid system and is connected with the fluid pool or the fluid drive system of outside.The research group in DAVIS branch school, University of California has proposed to utilize the various interface of mechanical joggle, and the adapter of circle foreign side connects microfluidic channel and outside fluid source in the corrosion.They propose a kind of method of utilizing glass capillary interface microfluid again simultaneously.Corrosion micropore ring is fixed on kapillary in the micropore on silicon chip, and fluid enters runner by kapillary and micropore.In addition, the material of tubule has stainless steel tube, poly-tetrafluoro etc.The purifying function of micro-fluid chip mainly adopts electric field or magnetic field that charged fluid is separated.Typical application electrophoresis chip and cytorheology measured chip.The method of optical detection is mainly adopted in the detection of chip.Different application purpose according to chip adopts different detection meanss at present.The typical application example is a capillary electrophoresis chip, adopts the CCD scan method that band images different on the chip is noted, and utilizes special-purpose imgae processing software that the result of CE is analyzed.Method of focusing is to weak signal (fluorescent signal) detection altogether to adopt similar laser in addition, and typical example is a gene chip tester.

In view of the huge potential industrial value of microfluid system, a large amount of investigation and the preliminary research of our processes utilizes the micro-fluid chip of various available advanced manufacturing technologies development miniaturizations and microminiaturization and comprises micro-fluidic chip and the miniature flow cytometer of the optical table of compactness.

At traditional flow cytometer complexity, be unfavorable for the deficiency of individuation diagnosis and treatment proposing a kind of flow cytometer based on microflow control technique.The objective of the invention is practicality and personalized demand, develop a kind of miniature flow cytometer in order to improve flow cytometer.

A kind of flow cytometer based on microflow control technique is to adopt following scheme to realize: miniature flow cytometer primary structure is regulated platform, signal processing case, tie cable, main control system etc. and is formed by base, cabinet, removable micro-fluidic chip, compact optical detection unit, fluid input/output interface, micrometric displacement.Base is fixed on the cabinet, micro-displacement platform is fixed on the base, micro-fluidic chip is fixed on the micro-displacement platform, the fluid input/output interface is connected with micro-fluidic chip by platform, optical detection unit is positioned at the top of micro-fluidic chip, finish optical detection by regulating relative position, the separation unit on the chip is finished sorting work simultaneously.

Its principle of work is: the input and output of fluid process fluid enter the passage of microfluid, because the microfluidic channel width dimensions is at 2-4 times of particle dia, the particle alignment that enters runner is embarked on journey, laser apparatus or optical fiber are introduced detection zone with exciting light, when particle passes through detection zone, light generation scattering and fluorescence excitation, place in the place ahead of runner low-angle detector with incident light and the scattered light placement wide-angle detector of cross surface vertical direction mutually, in order to collect large angle scattering and fluorescence.Through laser radiation, cell was to all direction scattered beams of space 360 degree solid angles when cell passed through detection zone in liquid stream, and the signal of scattering is relevant with the specific refractory power of the size of cell, shape, plasma membrane and cell interior.The intensity of small angle scattering is relevant with the size of cell.The specific refractory power of large-angle scattered light cell membrane, kytoplasm, nuclear membrane is comparatively responsive, and is information-related with the fine structure and the particle properties of cell interior.When producing fluorescence under the irradiation at incident light behind the cell dyeing, collect by the large angle scattering detector.The Small angle detector adopts photorectifier, and the wide-angle detector adopts photomultiplier.Classify from functional module, comprise the separation unit (4) and the Controlling System (5) of the microfluid unit (1) that can change arbitrarily and optical detection unit (2) and fluidic input-output unit (3), fluid particles based on its composition of flow cytometer of microflow control technique.

According to the present invention (1), the microfluid unit adopts the method for the microfabrication of traditional IC to obtain or little injection moulding process.The cross section of fluid channel can be shapes such as semicircle, square, trapezoidal, trilateral, hexagon.The material of injection moulding can be a polycarbonate, silica gel, tetrafluoroethylene etc.Detection window processes on the cover plate of runner.Runner adopts methods such as accurate electrical spark, electrolysis, line cutting, laser processing to obtain.The diameter of runner is in fluid between 1 times to 4 times of maximum particle dia.According to the present invention (2), optical detection unit comprises laser apparatus, beam expanding lens group, condensing lens group, various combination of devices such as optical splitter mirror group, colour filter group, electrooptical device.When fluid or sheath stream are flowed through microfluidic channel, the arrangement because cell or particle are embarked on journey, incident light and cell interaction cause scattering of light or fluorescence excitation.According to the present invention (3), flexible pipe, kapillary, scalp needle tubing etc. are adopted in the fluidic input and output.The method that adopts corrosion or punch processes the interface of fluid input and output at the two ends of fluid channel, in order to improve the sealing property of liquid, go out to adopt the little obturator of rubber at interface, the little valve one control fluid of fluid is installed is simultaneously entered runner.The fluidic sample introduction adopts pressure sample introduction, methods such as ram pump sample introduction, electric osmose sample introduction.According to the present invention (4), at the both sides of sprue processing microelectrode, after the particle in the convection cell finishes identification, apply electric field to particle and this section fluid column, open little valve of sorting branch road inlet simultaneously, particle is drawn to branch road gets on, finish sorting particle.According to the present invention (5), the fluidic sample introduction detects data, and the adjusting of light source etc. is finished by control software, under the irradiation of the cell in the liquid,, collect the correlation parameter of each cell by the detector that is placed on all directions to all directions emission scattered light and fluorescence at laser.Conversion is processed into various results by control software through A/D in the output of detector.

The present invention compares with existing commercial flow cytometer has following advantage: (1) owing to adopt the microfluidic control chip, instrumental function is with commercial identical, but instrument miniaturization is easy to carry; (2) owing to adopt compact optical detection design, carry out push-in the connection between chip and the optical detecting platform, adopt simultaneously and regulate platform automatically and finish optical alignment, easy and simple to handle; (3) push-in fluid interface seals reliable and secure.

The utility model is described in further detail below in conjunction with accompanying drawing.

Fig. 1 is body unit and optical detection synoptic diagram, and dotted line is represented erythrocytic scattered light.

Fig. 2 is an ambient fluid sample introduction synoptic diagram.

Fig. 3 is a PDMS fluidic access diagram.

Fig. 4 is the block diagram of Controlling System.

With reference to accompanying drawing 1, according to the present invention, the design of element of fluid and detection as shown in Figure 1.Fig. 1 element of fluid and optical detection synoptic diagram, dotted line is represented erythrocytic scattered light, laser apparatus 1, optical fiber 2, focus head 3, wide-angle detector 4, camera lens 5, Small angle detector 6, Resistance 7, microfluid substrate and cover glass 8, red corpuscle is in runner during directed flow, the light of laser apparatus 1 incides runner 8 intersections through optical fiber 2 and focus head 3 (488NMHE-NA laser apparatus), at the measurement zone light beam on the surface of cell to all directions scattering, small angle scattering illumination forward is mapped on the Small angle detector 6, directly the light of reflection is blocked district's 7 partitions, reduce detection noise, fluorescence and large-angle scattered light shine on the large angle scattering detector 4.The photosignal of detector enters the A/D collection plates through amplifying, and utilizes data processing software to obtain the various processing figure of different scattering strengths, thereby the characteristic of particle is characterized.

According to the present invention, ambient fluid sample introduction synoptic diagram, as shown in Figure 2.Regulate the break-make of fluidic head pressure and variable valve, obtain the sample introduction of micro fluid.Micro-fluid chip 10 is placed on the back up pad 9, processes input/output port 12 and 14 at chip 10, fluid channel 13, and cover glass 11 and 10 bondings constitute the runner of sealing.The fluid of fluid liquid storage tank 17 enters fluid channel under the control of magnetic valve 16, fluid flows into expense liquid pool 15 at last.

According to the present invention, PDMS fluidic passage as shown in Figure 3.Fluid chip interface board 18 has interface 19 and miniflow guidance tape 20 and transmitter and control circuit board 21 bondings formation micro-fluid chip.On the miniflow guidance tape, have sorting branch road and relevant little valve.

According to the present invention, the block diagram of Controlling System as shown in Figure 4.System enters the instrument that module controls forms the hardware organic connections functionalization under the control at main interface.

Claims (2)

1, a kind of flow cytometer based on microflow control technique, it is characterized in that: primary structure is by base, cabinet, removable micro-fluidic chip, compact optical detection unit, the fluid input/output interface, micrometric displacement is regulated platform, the signal processing case, tie cable, main control system is formed, base is fixed on the cabinet, micro-displacement platform is fixed on the base, micro-fluidic chip is fixed on the micro-displacement platform, the fluid input/output interface is connected with micro-fluidic chip by platform, optical detection unit is positioned at the top of micro-fluidic chip, micro-fluidic chip comprises interface board, runner plate, transmitter and circuit card are formed, and on the miniflow guidance tape runner are arranged, the little valve of sorting branch road and sorting.

2, a kind of flow cytometer based on microflow control technique according to claim 1, it is characterized in that: optical detection unit comprises laser apparatus, optical fiber, focus head, small angle scattering detector, large angle scattering detector and various mirror group.

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