CN1152256C - Electroosmotic current driven high-pressure perfusion pump - Google Patents
Electroosmotic current driven high-pressure perfusion pump Download PDFInfo
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- CN1152256C CN1152256C CNB011105062A CN01110506A CN1152256C CN 1152256 C CN1152256 C CN 1152256C CN B011105062 A CNB011105062 A CN B011105062A CN 01110506 A CN01110506 A CN 01110506A CN 1152256 C CN1152256 C CN 1152256C
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- current driven
- driven high
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Abstract
The present invention discloses a high-pressure infusion pump for driving an electroosmotic flow, which is a non-piston valveless high-pressure infusion pump capable of converting electric energy into fluid flowing energy with accurate control of flow quantity. The pump can generate 0 to 45 MPa output pressure, the flow quantity is smaller than or equal to 2 mu L/min, and no minimum flow quantity limit exists. The high-pressure infusion pump is especially suitable for the fluid drive of a microflow system, for example, the moving phase drive of the separation analysis of a microflow liquid phase chromatograph (mu-HPLC), the improvement and enhancement of the separating and analyzing efficiency in the field of a capillary electrochromatograph (CEC), capillary electrophoresis (CE) and the like, and the infusion control of the microflow system.
Description
Technical field
The invention belongs to a kind of electroosmotic current driven high-pressure perfusion pump, specifically, belong to a kind of micro flux liquid chromatogram (transfusion control of the miniature flow system in the moving phase driving of the compartment analysis of μ-HPLC), capillary electric chromatogram (CEC), Capillary Electrophoresis fields such as (CE) that can be used for.
Background technology
Just notice electroosmosis as far back as Reuss in 1809, i.e. the phenomenon that under the effect of DC electric field, moves of liquid with respect to charged tube wall, but well used always.The main application of electroosmotic flow is a chemical analysis field, Pretorius in 1974 etc. are by being applied to electric field at the packed column two ends, having demonstrated high-voltage DC power supply can replace forcing pump to drive chromatogram (" Electro-osmosis-ANew Concept for High-speed Liquid Chromatography ", J.Chromatography, 9,23-30,1974), Jorgenson and Lukacs are applied to kapillary with this principle, are capillary electric chromatogram (CEC).CEC is meant and adopts the fused quartz capillary column, fill the stationary phase that HPLC uses in the post, micro column liquid chromatography with the electric field force driving, promptly use electroosmotic flow (ElectroosmoticFlow, EOF) replace pressure to promote capillary electric chromatogram moving phase, separated according to the difference of solute different and self electrophoretic mobility (electric field action) of partition factor (or distribution principle) in moving phase and stationary phase.CEC is that it replaces pressure-driven to flow mutually with EOF with the fundamental difference of HPLC, and this is the thought basis of no piston valveless electroosmotic current driven high-pressure perfusion pump invention.
Although electroosmosis is familiar with by people very early, used EOF also existing 30 years, the applied research that really effectively has commercial value is just since 1996 years.The porous stem stem electroosmotic pump that is used for the FIA system of inventions such as He Youzhao (He Youzhao, Gan five or two, Chinese patent application ZL97,212,126; 1997) use the operating voltage of hundreds of volt low-voltage dc power supplies as pump, flow adjustment range is that per minute is counted microlitre to milliliter (μ L-mL/min) level, and output pressure is several MPas at zero point (MPa); Its significant disadvantages is the non-stop run time of pump can only continue several hrs, and microlitre still is difficult to accurate control with down-off, and output pressure is low, and the moving phase that can not satisfy the liquid chromatography compartment analysis far away drives requirement.Electronic high-pressure hydraulic (the Paul of invention such as Paul, etal United States Patent 6,019,882, February 1,2000) be no piston valveless high-pressure hydraulic truly, can access 17MPa (promptly 2, pressure 500Psi), and foretell that theoretically EOF can produce the pressure up to 35MPa; But the enforcement of this patent runs into following fatal problem: the electrochemical process of electrode surface in buffering liquid always will produce gas, the long slightly bubble that just forms of time.In direct driving system, bubble enters in the capillary column inevitably, and electric-force gradient becomes at the bubble place greatly, and the part produces higher Joule heat and makes bubble volume expansion, causes liquid stream to open circuit and the electric osmose interruption; In indirect driving system, the gathering of gas can cause that bubble is counter goes into the electric osmose post, and the electric osmose process is interrupted.So this pump can not continuous working, and is impracticable.
(technology of μ-HPLC) and capillary electric chromatogram (CEC), miniature flow analysis (usually relate to the problem of liquid with precise control tiny flow quantity in the system of μ-FIA) in the micro high efficiency liquid chromatography.Several microlitres of per minute to transporting of liquid of milliliter level can use prior mechanical commodity pump accurately to control; And per minute is counted microlitre and microlitre and is transported with the high pressure of subordinate's liquid and be difficult to accurately control with existing general goods pump, invent for this reason and a kind ofly be used for accurately controlling micro updating and microlitre not have piston valveless micro-infusion pump with the high pressure of down-off be very necessary, states such as the U.S., Korea S, Sweden, Japan have done a large amount of explorations to the problem of liquid with precise control tiny flow quantity, but make slow progress.
Summary of the invention
The object of the present invention is to provide a kind of electroosmotic current driven high-pressure perfusion pump, this pump can be used for the liquid driven of the micrometeor system of accurate Control Flow, can provide per minute to receive and rise to the liquid delivery rate of microlitre (nL～μ L/min) level and the output pressure more than 0～45MPa.
To achieve these goals, the present invention adopts following principle:
The mineral molecule is because its big specific surface usually produces the unsaturation of key, cause its surface to lose electric neutrality and charged, the ion that has an opposite charges with particle surface in polar solvent or electrolyte solution is attracted on its surface with its electric charge of balance, and this effect realizes by the coulomb reciprocation.In general, belong to strong physisorption, be called fixed layer near one deck of particle surface, its effect is balance ultramicron surface electrically; From the more weak adsorbed layer of ultramicron then formation far away slightly, be called dispersion layer.Because anxious poly-decline of strong adsorbed layer inner potential slowly reduces in weak adsorbed layer, the result produces the current potential downward gradient in whole adsorbed layer.Above-mentioned two-layer formation electrostatic double layer.The present invention utilizes the electric osmose drive principle of current-carrying, and promptly at the quartz capillary interface particularly under the situation of filler particles surface charging, the current-carrying of band heterocharge is made the electric osmose travel motion in the diffusion layer under External Electrical Field.The Smoluchowski equation that employing is similar in the capillary zone electrophoresis (CZE) provides the EOF expression formula
Ueo＝ε
0ε
rζE/η (1)
Ueo is an electric osmose speed in the formula, ε
0Be permittivity of vacuum, ε
rBe the current-carrying specific inductive capacity, ζ is that Zeta potential is an eletrokinetic potential, and η is the fluid viscosity coefficient, and E is an electric field intensity;
Electric osmose flow Q can be expressed as:
Q＝Ueo A＝ε
0ε
rζEA/η (2)
Wherein A is a net sectional area.By selecting for use different electric osmose media and connected mode to change flow range, regulate field intensity and change the current-carrying flow like this, conversion field intensity direction changes current-carrying and flows to.
The diffusion layer Potential Distributing that produces electroosmosis meets the Gouy-Chapman theory, promptly can be expressed as when ζ is little:
Ψ＝F(ζ)e
-κx
F in the formula (ζ) is the function of ζ, x be in the diffusion region somewhere to the distance of adsorbed layer.κ decision diffusion layer electromotive force increases the speed that descends, κ with distance x
-1Claim electrostatic double layer thickness again;
κ
-1＝(∑n
iz
i 2e
2/ε
0ε
rkT)
-1/2 (3)
In the formula, k is the Boltzmann constant, and T is an absolute temperature, and e is an electron charge.By (2) (3) as seen, diffusion layer reach and solution ion strength n
iWith electricity price z
iRelevant.When water is made current-carrying, κ
-1Maximum, electric osmose flow and range of adjustment are bigger.
In existing under the situation of direct current external electric field, there is frictional resistance in the especially small filler particles of migration liquid and capillary wall surface surface in the diffusion layer of generation electroosmosis, balance between them has determined the motion of liquid in the diffusion layer, and electric osmose power then depends on the electric field force that acts on diffusion layer and " excessive charge " in the diffusion layer; Polar solvent or electrolyte solution will flow to negative pole end from positive terminal capillaceous under the effect of electric osmose power, form electroosmotic flow (EOF) thus, if the output terminal at EOF adds a resistance, liquid stream will accumulate in output terminal and form the electric osmose pressure electric osmose power of contending with, till the two reaches balance.When electroosmotic flow is output as zero, can obtain top pressure output, as a same reason, when electric osmose pressure is zero, can obtain the highest electroosmotic flow output.
The miniature electroosmotic current driven high-pressure perfusion pump of no piston valveless is to fill quartz capillary chromatographic column or blank pipe capillary chromatographic column by one or several internal diameter less than 200 μ m, in fill out the filler (silica gel, finishing silica gel, ion exchange resin, polymer microsphere, inorganic ball-type or unformed filler, interior moulding filler) of particle diameter less than 10 μ m, form the pump housing by series, parallel combination; And provide electric osmose power by single high-voltage power supply for single-stage or multistage liquid transport pump, output pressure be multistage pump add and; Produce high pressure by electroosmotic flow in flow in capillary tube; Get rid of the bubble that electrode produces by the depassing unit system; Regulate delivery rate and pressure by control voltage or electroosmotic flow, to satisfy various micrometeor transfusion requirement; Can be for a long time uninterrupted continuous working of this pump, flow range≤2 μ L/min and do not have the minimum flow restriction.
The concrete technical scheme of the present invention is as follows:
The output terminal that flows in electroosmotic flow adds a resistance, the liquid stream aggregation forms the electric osmose pressure electric osmose power of contending with at output terminal, produce the electric osmose high pressure, regulate the no piston valveless electroosmotic current driven high-pressure perfusion pump system of delivery rate and pressure by control voltage or electroosmotic flow, it is characterized in that, be in series with the air scavenge device at delivery side of pump, and satisfy following condition as the single-stage electroosmotic current driven high-pressure perfusion pump:
Used capillary chromatographic column adopts the kapillary of internal diameter 50-200 μ m, and packing material size is 1-10 μ m;
Electrode used therein adopts the coreless armature of internal diameter 100-200 μ m;
Used conduit adopts the kapillary of 10-100 μ m;
Flow range is≤2 μ L/min.
Filler is selected a kind of in silica gel, finishing silica gel, ion exchange resin, polymer microsphere, inorganic ball-type or unformed filler, the interior moulding filler for use.
Coreless armature adopts inert metal, alloy, conducing composite material and conductive plastic material, as platinum, metallic cementation pottery, conductive plastics or copper etc.
The air scavenge device is made of the hollow chamber of a carrying liqs input port, delivery outlet and exhausr port (in be coated with hydrophobic material), from liquid inlet input liquid, liquid outlet discharged liquid through hollow chamber bottom is discharged and contain the exhausr port that the liquid of gas is provided with by hollow cavity top (on add a resistance).
Constitute multistage pump by a plurality of series connection of single-stage electroosmotic current driven high-pressure perfusion pump, be in series with the air scavenge device at delivery side of pump.
Constitute multistage pump by a plurality of series connection of single-stage electroosmotic current driven high-pressure perfusion pump, only drive the series multistage pump simultaneously with single group power supply.
Constitute multistage pump by the parallel connection of single-stage electroosmotic current driven high-pressure perfusion pump, be in series with the air scavenge device at delivery side of pump; This pump can be used as polynary gradient elution pump, to satisfy special transfusion requirement.
Each is in parallel or series connection single-stage electroosmotic current driven high-pressure perfusion pump is connected respectively again and/or single-stage electroosmotic current driven high-pressure perfusion pump in parallel constitutes the combined multi-stage pump.
Coreless armature is two logical, threeway or logical coreless armature how.
Description of drawings
Below in conjunction with drawings and Examples the present invention is described in detail.
Fig. 1 is the synoptic diagram of single-stage electroosmotic current driven high-pressure perfusion pump;
Fig. 2 constitutes the synoptic diagram of multistage pump for the series connection of single-stage electroosmotic current driven high-pressure perfusion pump;
Fig. 3 is the single-stage electroosmotic current driven high-pressure perfusion pump synoptic diagram that constitutes multistage pump in parallel;
Fig. 4 is that each is in parallel or series connection single-stage electroosmotic current driven high-pressure perfusion pump is connected respectively again and/or the synoptic diagram of single-stage electroosmotic current driven high-pressure perfusion pump in parallel formation combined multi-stage pump.
Fig. 5 is the air scavenge schematic representation of apparatus.
Among the figure: the 1-capillary chromatographic column; The 2-conduit; The 3-coreless armature; 3 '-the threeway coreless armature; 3 " lead to coreless armature more; 4-air scavenge device; 5-constant voltage/constant current control device; The 14-liquid inlet; The 15-liquid outlet; The 16-exhausr port.
Embodiment
Embodiment 1: see Fig. 1, be the single-stage driving pump.Copper hollow two logical (3) its internal diameter 200 μ m are as electrode and fluid passage, chromatographic column (1) adopts column length 20cm, internal diameter 75 μ m packed columns, in fill out the silica filler of particle diameter 5 μ m, conduit (2) internal diameter 100 μ m, aqueous ph value is 6.5, driving voltage 13.0-26.0KV, flow range 0.3000-0.4000 μ L/min, output pressure 2.5-7.5Mpa.Air scavenge device (4) is made of the hollow chamber of a liquid inlet (14), delivery outlet (15) and exhausr port (in be coated with hydrophobic material), from liquid inlet input liquid, liquid outlet discharged liquid through hollow chamber bottom is discharged and contain the exhausr port (16) that the liquid of gas is provided with by hollow cavity top (on add a resistance).Relevant air scavenge device (4) can be referring to shown in Figure 5.
Embodiment 2: see Fig. 2, be the secondary drive pump, constitute 2 grades of pumps by 2 series connection of single-stage electroosmotic current driven high-pressure perfusion pump, be in series with the air scavenge device at delivery side of pump.Stainless steel hollow two logical internal diameter (3) 100 μ m are as electrode and fluid passage, chromatographic column (1) adopts internal diameter 50 μ m packed columns, in fill out the silica filler of particle diameter 1 μ m, conduit (2) internal diameter 50 μ m, all the other conditions are with embodiment 1, driving voltage 8.0-15.0KV, flow range 0.2500-0.9500 μ L/min, output pressure 3.5-15MPa.Except that 2 grades of pumps of present embodiment, can constitute multistage pump by the same principle series connection.The multistage pump that series connection constitutes only can drive the multistage pump of series connection simultaneously with single group power supply.
Embodiment 3: the secondary drive pump, and metallic cementation ceramic hollow two logical internal diameter 150 μ m adopt internal diameter 200 μ m packed columns as electrode and fluid passage, in fill out the ion exchange resin of particle diameter 5 μ m, catheter diameter 10 μ m, all the other conditions are with embodiment 1, and experimental result is with embodiment 2.
Embodiment 4: the secondary drive pump, and conductive plastics hollow two logical internal diameter 200 μ m adopt internal diameter 100 μ m packed columns as electrode and fluid passage, in fill out the polymer microsphere of particle diameter 2 μ m, catheter diameter 75 μ m, all the other conditions are with embodiment 1, and experimental result is with embodiment 2.
Embodiment 5: the secondary drive pump, and platinum system hollow two logical internal diameter 150 μ m adopt internal diameter 150 μ m packed columns as electrode and fluid passage, in fill out the inorganic ball-type filler of particle diameter 10 μ m, catheter diameter 50 μ m, all the other conditions are with embodiment 1, and experimental result is with embodiment 2.
Embodiment 6: the secondary drive pump, and stainless steel hollow two logical internal diameter 100 μ m adopt internal diameter 50 μ m packed columns as electrode and fluid passage, in fill out the unformed filler of particle diameter 10 μ m, catheter diameter 100 μ m, all the other conditions are with embodiment 1, and experimental result is with embodiment 2.
Embodiment 7: the secondary drive pump, the logical internal diameter 200 μ m of conductive plastics hollow two adopt internal diameter 100 μ m packed columns as electrode and fluid passage, in fill out in the moulding filler, catheter diameter 75 μ m, all the other conditions are with embodiment 1, experimental result is with embodiment 2.
Embodiment 8: see Fig. 3, three grades of driving pumps constitute multistage pump by the parallel connection of single-stage electroosmotic current driven high-pressure perfusion pump, are in series with air scavenge device (4) at delivery side of pump.The hollow threeway of copper (3 ') is as electrode and fluid passage, chromatographic column 1: column length 20cm, internal diameter 200 μ m, in fill out the silica filler of particle diameter 5 μ m; Post 2: column length 18cm, internal diameter 100 μ m, in fill out the silica filler of particle diameter 5 μ m; Post 3: with post 1; Aqueous ph value is 6.5, driving voltage 8.7-17.4KV, flow range 0.2500-0.7000 μ l/min, output pressure 1.6-4.8MPa.This pump can be used as polynary gradient elution pump, to satisfy special transfusion requirement.
Description according to above each embodiment, be easy to imagine, in actual applications can also be with each in parallel or series connection single-stage electroosmotic current driven high-pressure perfusion pump series connection and/or single-stage electroosmotic current driven high-pressure perfusion pump in parallel constitute the combined multi-stage pump respectively again, used coreless armature correspondingly is many logical coreless armatures, as shown in Figure 4.
Claims (9)
1, a kind of single-stage electroosmotic current driven high-pressure perfusion pump, be to add resistance at the output terminal that electroosmotic flow flows, the liquid stream aggregation forms the electric osmose pressure electric osmose power of contending with at output terminal, produce the electric osmose high pressure, regulate the no piston valveless electroosmotic current driven high-pressure perfusion pump system of delivery rate and pressure by control voltage or electroosmotic flow, it is characterized in that, be in series with the air scavenge device, and satisfy following condition as the single-stage electroosmotic current driven high-pressure perfusion pump at delivery side of pump:
A. used capillary chromatographic column adopts the kapillary of internal diameter 50-200 μ m, and packing material size is 1-10 μ m;
B. electrode used therein adopts the coreless armature of internal diameter 100-200 μ m;
C. used conduit adopts the kapillary of 10-100 μ m;
D. flow range is≤2 μ L/min.
2, single-stage electroosmotic current driven high-pressure perfusion pump according to claim 1 is characterized in that described filler selects a kind of in silica gel, finishing silica gel, ion exchange resin, polymer microsphere, inorganic ball-type or unformed filler, the interior moulding filler for use.
3, single-stage electroosmotic current driven high-pressure perfusion pump according to claim 1 is characterized in that described coreless armature adopts inert metal, alloy, conducing composite material and conductive plastic material.
4, single-stage electroosmotic current driven high-pressure perfusion pump according to claim 1, it is characterized in that described air scavenge device is made of the hollow chamber of a carrying liqs input port, delivery outlet and exhausr port, from liquid inlet input liquid, liquid outlet discharged liquid through hollow chamber bottom, and the liquid that contains gas is discharged by the exhausr port that hollow cavity top is provided with.
5, a kind of electroosmotic current driven high-pressure perfusion pump is characterized in that it being to constitute multistage pump by a plurality of series connection of the described single-stage electroosmotic current driven high-pressure perfusion pump of claim 1-4, is in series with the air scavenge device at delivery side of pump.
6, a kind of electroosmotic current driven high-pressure perfusion pump is characterized in that it being to constitute multistage pump by a plurality of series connection of the described single-stage electroosmotic current driven high-pressure perfusion pump of claim 1-4, only drives the series multistage pump simultaneously with single group power supply.
7, a kind of electroosmotic current driven high-pressure perfusion pump is characterized in that it being to constitute multistage pump by the parallel connection of the described single-stage electroosmotic current driven high-pressure perfusion pump of claim 1-4, is in series with the air scavenge device at delivery side of pump; This pump can be used as polynary gradient elution pump, to satisfy special transfusion requirement.
8,, it is characterized in that each is in parallel or series connection single-stage electroosmotic current driven high-pressure perfusion pump is connected respectively again and/or the described single-stage electroosmotic current driven high-pressure perfusion pump of claim 1-4 in parallel constitutes the combined multi-stage pump according to claim 5 or 7 described electroosmotic current driven high-pressure perfusion pumps.
9,, it is characterized in that used coreless armature is two logical, threeway or logical coreless armature how according to claim 1,5,7 or 8 described electroosmotic current driven high-pressure perfusion pumps.
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| CNB011105062A CN1152256C (en) | 2001-04-06 | 2001-04-06 | Electroosmotic current driven high-pressure perfusion pump |
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|---|---|---|---|
| CNB011105062A CN1152256C (en) | 2001-04-06 | 2001-04-06 | Electroosmotic current driven high-pressure perfusion pump |
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| CN1152256C true CN1152256C (en) | 2004-06-02 |
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| JP4086001B2 (en) * | 2004-03-25 | 2008-05-14 | 株式会社島津製作所 | Liquid chromatograph pump |
| CN100378454C (en) * | 2005-04-01 | 2008-04-02 | 中国科学技术大学 | Dynamic and complete analysis system for dynamic electric current |
| CN101093227B (en) * | 2007-06-14 | 2011-09-14 | 山东师范大学 | Gravity drive pump of microflow controlled chip system |
| CN102331473A (en) * | 2011-09-09 | 2012-01-25 | 李彤 | Phase change actuating fluid delivery pump |
| CN110373325B (en) * | 2019-07-11 | 2020-11-06 | 上海交通大学 | Trace blood hatching device and trace blood hatching method |
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