CN101266255A - Intelligent non-contact type minim biological reagent distribution method and its dispensing system - Google Patents

Abstract

The invention provides a intelligent non-contact type method for distributing trace biology agent and distributing system. A micro-flow detecting sensor is integrated on the distributing system by combining the MEMS technique and the intelligent control method and presupposing a great variety of knowledge information are used to perform the self-adapting automatic and intelligent adjustment of all kinds of the distribution parameters and strategies during high pass rapid cycle distribution process, therefore the accurate, trace agent not-contact type distribution can be realized direct towards all kinds of viscosity agent and all kinds of external condition effects. The automatic and intelligent adjustment of control parameters and the fault real-time monitoring and diagnosing function can be quickly performed to prevent the factors variation such as remain agent amount, environment temperature, agent viscosity or the like from influencing the distribution precision, so as to really ensure the exact size trace agent distribution, therefore the accuracy and reliability of the agent distribution can be increased. The distributing system has function of automatic calibration and searching the optimal control parameter, high agent viscosity adaptation character to satisfy the distribution requirement of the extensive volume (nanoliter to milliliter).

Description

Intelligent non-contact type distributes the method and the distribution system thereof of minim biological reagent

(1) technical field

The present invention relates to technical field of bioengineering, be specifically related to plurality of reagents in the high flux operating process carry out intelligence, trace, fast, the method for accurately distributing.

(2) background technology

The biological reagent treatment technology is one of laboratory facilities the most commonly used in the Life Science Experiment, plays crucial effects at technical field of bioengineering such as the screening of crystallization of protein, medicine, Biochemistry Experiments.For example, in the protein crystal procurement process, need the crystallization conditions such as specific concentration, reductive agent and detersive of pH value, ionic strength, salt be optimized, the precision of biological reagent absorption, transfer and micro-batch operation and speed become the main bottleneck that restriction protein structure assay method develops; In the drug research field, be the main path that obtains new drug as the high-throughput screening method of experimental tool carrier with microplate.In order further to improve the screening flux, must constantly reduce the volume of biological reagent proportioning in the single test, improve constantly the precision that reagent distributes, thereby promote the speed of drug screening and development to improve constantly; Equally, in some other biological research fields, as the research of gene sequencing, mononucleotide polymorphic Genotyping, and aspect such as Biochemistry Experiment, require the agent treated level to improve constantly equally, realize microlitre even receive the fast high-flux of upgrading reagent distributing and shifting.Simultaneously, along with experimental implementation develops to the high flux direction, to distributing reliability, speed etc. are also had higher requirement.

About the research of liquid reagent distribution technique always in continuous development, present existing all ingredients distribution method, according to nozzle or needle point whether with container or substrate contacts, the reagent distribution method can be divided into contact and contactless allocation scheme.Initial trace reagent distributes employing contact distribution method, and it is to move in injection tube by the Electric Machine Control piston, realizes the absorption or the distribution of trace reagent.Adopt this method, can measure the dosage that distributes reagent, be not subjected to the influence of reagent viscosity by the motion of control piston.Having occurred contactless allocation scheme afterwards, is exactly in fact under external force, when the reagent extrusion nozzle, and the influence that can provide enough energy to overcome drip gauge surface tension, viscosity etc., thus realize the process that drop and nozzle come off.Contactless distribution method has air pressure to drive according to the type of drive difference, hydraulic-driven, and Piezoelectric Driving, thermal enlargement drives, several different methods such as electric field driven.

In the above the whole bag of tricks, contact reagent distribution method based on piston motion can the control piston motion accurately be extruded reagent, but can not provide enough energy to spray reagent fast, dispensing head need be contacted the transfer that realizes reagent with the bottom of carrying vessel.In solenoid control air pressure or hydraulic-driven method, overcome contact distribution method deficiency, but also need be at the variation that distributes reagent viscosity, folding time and the pressure source pressure and other parameters of adjusting solenoid valve realize accurate distribution.The mode of Piezoelectric Driving can't adapt to the big reagent of viscosity, distributes the type of reagent to be restricted, and its reliability is still waiting further raising, and the commercialization process is also slow.Some other trace reagent distribution methods such as heat expansion and acoustic excitation also are in conceptual phase.More than the various distribution methods of mentioning, also all need experience and test operation repeatedly for the adjustment of allocation of parameters, calibration.The user must the cooperation of producer with instruct under use distributing equipment.

(3) summary of the invention

The object of the present invention is to provide a kind of precise volumes reagent of can realizing to distribute, have the method and the distribution system thereof of the contactless distribution minim biological reagent of extremely strong viscosity adaptability intelligent.

The object of the present invention is achieved like this: intelligent non-contact type distributes the method step of minim biological reagent to be: in the circulation of reagent distribution each time, the flow rate information of the continuous flow sensor feedback of control system is carried out integration, obtain in solenoid valve is opened time t velocity integral both t distribute reagent volume Vt in the time, the velocity integral of whole assignment period T is information such as reagent actual allocated reagent volume VT and mean flow rate both, be that control cycle is when consistent with assignment period when n gets 1, after distribution follows each time, control system can be according to reagent dispensed volume VT last time, postpone volume VT-Vt, and information such as required dispensed volume V0, adopt the FUZZY ALGORITHMS FOR CONTROL judgement to calculate the required solenoid valve that next time circulates and open time t, control system is constantly monitored flow information and is adjusted electromagnetic valve switch time t, realizes accurately reagent distribution in the global scope.Simultaneously, in order to make system, in the middle of first fuzzy control circulation, adopt delay compensation method to come the rapid adjustment solenoid valve to open time t fast near the ideal Distribution state.Promptly according to postponing volume dt, with the volume v of needs distribution ₀Deduct the delay volumetric point dt of overabsorption owing to postpone.Like this, the real-time integration of flow velocity in the following sub-distribution is when the dispensed volume of integration equals v ₀During-dt, close solenoid valve, and record opening time t at this moment ₀, as next adopt fuzzy control strategy carry out closed-loop control initial opening time t.In addition, flow feedback cycle and closed-loop control cycle are not synchronous in the native system.After system stability, for improving system's arithmetic speed, can also increase control cycle, in several sub-distribution circulation backs or error during, carry out the closed-loop control adjustment again, the dirigibility that improves system greatly greater than setting value.

Distribution system is mainly by syringe pump, the 4-2 introduction valve, the reservoir pressure reagent bottle, pressure regulating system, solenoid valve, motion platform, flow sensor and intelligence operation control system are formed, the reservoir pressure reagent bottle connects the ambient pressure source by pressure regulating system, syringe pump connects syringe, motion platform is arranged on the pipe system below, flow sensor is arranged on the solenoid valve top, the 4-2 introduction valve connects the reservoir pressure reagent bottle respectively, solenoid valve and syringe, the intelligence operation control system connects the 4-2 introduction valve respectively, solenoid valve, motion platform, flow sensor and pressure regulating system.

The present invention adopts the form of pressure/solenoid valve combination, discloses a cover non-contacting micro reagent distribution method.Adopt this method to carry out theory diagram that single channel reagent distributes as shown in Figure 1-Figure 3.During the system initialization, introduction valve deflection right side, syringe pump drives syringe piston and moves downward, from reagent bottle extraction system liquid, on the left of the introduction valve deflection, syringe pump drives piston and moves upward afterwards, reagent is filled in the pipe system, and this action repeats to finish for several times the cleaning and the filling of pipeline.When reagent was drawn, introduction valve forwarded the left side to, and solenoid valve is opened, and utilized the piston precise motion to realize the absorption of reagent.When drawing reagent to be allocated,, pollute and waste, can draw a bit of air or silicone oil earlier system liquid and reagent to be allocated are separated if worry system liquid and reagent mix to be allocated.Reagent divides timing, and introduction valve motion turns to top position and precompressed reagent bottle to connect, open solenoid valve after, reagent sprays from nozzle under pressure, realizes contactless distribution.At this moment, can regulate and distribute reagent volume by control electromagnetic valve switching time and pressure size.Concrete time and pressure parameter system are according to sensor feedback flow information and set information configuration and intelligent adaptive adjustment automatically.

In fact, in a large amount of reagent batch operation processes, because the system residual amount constantly reduces, cause that the liquid viscosity value changes a little in the distribution circuit system, simultaneously, ambient temperature also can influence viscosity and change, cause like this under the same system pressure effect, flow velocity can change or fluctuate; And, also have the interference of some the unknowns also can influence flow velocity generation fluctuation.Simultaneously, in the trace reagent assigning process, owing to distribute reagent volume small, flow velocity u can not infinitely reduce in order to ensure contactless distribution, so the solenoid valve unlatching time is also shorter, like this, the influence that accurate reagent divides the timing operating lag just cannot be ignored.As shown in Figure 4, have delay phenomenon owing to reagent in solenoid valve unlatching time and the pipeline flows, closed electromagnetic valve signal output back is owing to delay phenomenon still has the outflow of part reagent.Like this, under the same controlled variable effect, can influence last each actual volume that distributes reagent owing to the fluctuation and the situations such as variation and delay of flow velocity.This method is in order to realize more accurate reagent batch operation, the remaining amount of reagent of distributing of opposing, ambient temperature, when viscosity changes to the influence of assignment accuracy.Concrete control idea is as follows:

As shown in Figure 1-Figure 3 in the theory diagram, a microflow sensor that utilizes the MEMS technology to develop voluntarily is integrated in the middle of the pipe system, flow rate information according to the flow sensor feedback, can control electromagnetic valve opening time self-adaptation adjust, thereby guarantee that each reagent volume of distributing is not subjected to disturbance, realizes accurately distributing.

Equally, according to above principle, this method can also be allocated in advance once at a kind of reagent to be allocated, and like this according to feedback information, system can be according to the adjustment strategy automatic adjustment system pressure of realizing storage, systematic parameters such as solenoid valve unlatching time.Needn't do a large amount of calibration tests like this and redefine system pressure and open-interval parameter, and, realize that precise volumes reagent distributes, and has extremely strong viscosity adaptability in conjunction with flow feedback information intelligent decision and the automatic controlled variable of adjusting.

The inventive method adopts the form of pressure/solenoid valve combination, flows by the pre-hydraulic fluid of solenoid control and realizes the batch operation of reagent.Dispensing head can not realized contactless distribution with substrate contacts in the reagent assigning process, and dispensing rate is fast, pollutes little.Have single titer noncontact distribution, many continuous and quantitative noncontacts distribution, single titer contacts distribution, many continuous and quantitatives contact distribution, plurality of reagents allocation models such as distribution of constant speed continuous injection and quantitative absorption.And system can Based Intelligent Control and limits in the pipeline pressure greater than critical value, guarantee that trace reagent distributes after, come off and can not adhere to and realize contactless distribution above it thereby have enough energy and nozzle; Function with real-time monitoring system distribution state in high flux circulates the reagent assigning process fast, at distributing the specificity of reagent situation of change, and the variation of other unknown integrated conditions, can carry out adjustment of controlled variable automated intelligent and fault monitoring and diagnostic function in real time fast, avoided the influence of various factorss such as residual agent amount, environment temperature, reagent viscosity variation to assignment accuracy, guaranteed that really the precise volumes trace reagent distributes, improved accuracy and reliability that reagent distributes; Have the function of automatic calibration and searching optimization control parameter, have extremely strong reagent viscosity adaptive character, satisfying on a large scale, volume (receive and rise to milliliter) distributes requirement.

(4) description of drawings

Fig. 1-Fig. 3 is the principle schematic of reagent assigning process;

Fig. 4 is for distributing reagent volume synoptic diagram in the circulation;

Fig. 5 is intelligent loop control theory synoptic diagram.

(5) embodiment

The present invention is further illustrated below in conjunction with accompanying drawing:

Present embodiment adopts the form of pressure/solenoid valve combination, has developed a cover non-contacting micro reagent distribution method.Distribution system is mainly by syringe pump, the 4-2 introduction valve, and the reservoir pressure reagent bottle, pressure regulating system, solenoid valve, motion platform, sensor and intelligence operation control system etc. are partly formed.During the system initialization, introduction valve deflection right side, the driven by motor syringe piston moves downward, from reagent bottle extraction system liquid, on the left of the introduction valve deflection, the driven by motor piston moves upward afterwards, reagent is filled in the pipe system, and this action repeats to finish for several times the cleaning and the filling of pipeline.When reagent was drawn, introduction valve forwarded the left side to, and solenoid valve is opened, and utilized the piston precise motion to realize the absorption of reagent.When drawing reagent to be allocated,, pollute and waste, can draw a bit of air or silicone oil earlier system liquid and reagent to be allocated are separated if worry system liquid and reagent mix to be allocated.Reagent divides timing, and introduction valve motion turns to top position and precompressed reagent bottle to connect, open solenoid valve after, reagent sprays from nozzle under pressure, realizes contactless distribution.At this moment, can regulate and distribute reagent volume by control electromagnetic valve switching time and pressure size.Concrete time and pressure parameter system are according to sensor feedback flow information and set information configuration and intelligent adaptive adjustment automatically.

The concrete thinking of its Based Intelligent Control and adjustment strategy is as follows:

1, volitional check controlled variable is guaranteed contactless distribution

Divide timing carrying out trace reagent,, usually can stick on the nozzle because reagent volume is less.

Reagent distributes in the back drop formation and the process that comes off, and the liquid flow process is influenced by following four kinds of power: fluid inertia force, viscosity pulls power, surface tension and gravity.In the trace reagent assigning process, the relation between these power can be described with following several dimensionless numbers, is respectively reynolds number Re, represents the ratio of inertial force and viscous force.Capillary is counted Ca, represents viscous force and capillary ratio.Weber number We represents inertial force and capillary ratio.The total Bo of nation (G) represents gravity and capillary ratio, specifically explains suc as formula shown in (1) to (4).

$\mathrm{Bo}\left(G\right)\≡\frac{\mathrm{\ρ}{R}^{2}g}{\mathrm{\σ}}---\left(1\right)$

$\mathrm{Re}\≡\frac{\mathrm{\ρuR}}{\mathrm{\η}}---\left(2\right)$

$\mathrm{Ca}\≡\frac{\mathrm{\ηu}}{\mathrm{\σ}}---\left(3\right)$

$\mathrm{We}\≡\mathrm{CaRe}=\frac{\mathrm{\ρ}{u}^{2}R}{\mathrm{\σ}}---\left(4\right)$

Wherein: ρ-density; σ-surface tension; η-viscosity; The u-flow velocity; The R-spout radius

Divide timing at trace reagent, jet size is little, and Bo is very little, and the influence of gravity is very little.We, Re and Ca have bigger influence to allocation result.It can also be seen that the viscosity of distributing reagent from formula, surface tension, density, and jet size and flowing velocity etc. all influence assigning process.Concrete influence is closed and is: reagent volume is smaller distributing, and ignores influencing under the situation of gravity, want to distribute reagent can be successfully and nozzle come off, the dimensionless number that these parameters are formed---We and Re must just can come off greater than critical value; Re, We are big more, and drop is easy more to come off, and the liquid bridge in the assigning process between main droplet and the nozzle is long more, when We is bigger, can form fluid column, splits into many droplets easily.For practical application, Re generally all satisfies condition, and key is will control We to satisfy condition; And the ratio of weber number and Reynolds number---capillary number (Ca), also influential to droplet profile, when Ca was big, it is flat that droplet profile can become.

According to above theory, in the time of distributing a kind of reagent, can import specificity of reagent information such as this reagent viscosity, density, again in conjunction with pipeline size information such as jet sizes, calculate We greater than critical value desired flow rates value,, determine system pressure then in conjunction with flow resistance information such as pipeline size.Like this control system automatically according to these information Adjustment System pressure greater than this lower limit, guaranteed that trace reagent divides the contactless distribution of timing.Simultaneously, be unlikely to again to adjust system pressure too high, cause solenoid valve can't higher frequency during work influence distribute small size reagent accurate.

2, intelligent close-loop feedback control is at guaranteeing accurately reliable the distribution under specificity of reagent variation and the other factors disturbance situation

As mentioned above, trace reagent divides the success that whether comes off of timing drop to realize that the key of contactless batch operation is the control of reagent mass flowing nozzle speed.And after pipe system configured, the adjustment of flow velocity can realize by the system pressure adjustment.Therefore, system's minimum pressure P at first is determined in order to ensure contactless distribution.And then, distribute the reagent body according to need, determine that according to formula (5) solenoid valve opens time t.

V＝πR ²ut (5)

Conventional reagent distributes control, perhaps to the less demanding occasion of assignment accuracy, can realize each opening time of reservation system pressure P and solenoid valve, carries out repeatedly cycle assignment fast, finishes a large amount of batch operations.

This distributes control procedure as shown in Figure 5.In the circulation of reagent distribution each time, the flow rate information of the continuous flow sensor feedback of control system is carried out integration, obtain like this in solenoid valve is opened time t velocity integral both t distribute reagent volume Vt in the time, the velocity integral of whole assignment period T is information such as reagent actual allocated reagent volume VT and mean flow rate both.Be that control cycle is when consistent with assignment period when n gets 1, after distribution follows each time, control system can be according to reagent dispensed volume VT last time, postpone volume VT-Vt, and information such as required dispensed volume V0, adopt Based Intelligent Control plan comprehensive intelligent to judge that calculating the required solenoid valve that next time circulates opens time t.Control system is constantly monitored flow information and is adjusted electromagnetic valve switch time t, realizes accurately reagent distribution in the global scope.

Claims (3)

1, a kind of intelligent non-contact type distributes the method for minim biological reagent, it is characterized in that: intelligent non-contact type distributes the method step of minim biological reagent to be: in the circulation of reagent distribution each time, the flow rate information of the continuous flow sensor feedback of control system is carried out integration, obtain in solenoid valve is opened time t velocity integral both t distribute reagent volume Vt in the time, the velocity integral of whole assignment period T is information such as reagent actual allocated reagent volume VT and mean flow rate both, be that control cycle is when consistent with assignment period when n gets 1, after distribution follows each time, control system can be according to reagent dispensed volume VT last time, postpone volume VT-Vt, and information such as required dispensed volume V0, adopt the FUZZY ALGORITHMS FOR CONTROL judgement to calculate the required solenoid valve that next time circulates and open time t, control system is constantly monitored flow information and is adjusted electromagnetic valve switch time t, realizes accurately reagent distribution in the global scope.

2, the method for a kind of intelligent non-contact type distribution minim biological reagent according to claim 1, it is characterized in that: in the described FUZZY ALGORITHMS FOR CONTROL, in the middle of first fuzzy control circulation, adopt delay compensation method to come the rapid adjustment solenoid valve to open time t, promptly according to postponing volume dt, with the volume v of needs distribution ₀Deduct the delay volumetric point dt of overabsorption owing to postpone.Like this, the real-time integration of flow velocity in the following sub-distribution is when the dispensed volume of integration equals v ₀During-dt, close solenoid valve, and record opening time t at this moment ₀, as next adopt fuzzy control strategy carry out closed-loop control initial opening time t; After system stability, can increase control cycle, in several sub-distribution circulation back or error during, carry out the closed-loop control adjustment again greater than setting value.

3, a kind of intelligent non-contact type according to claim 1 distributes the distribution system of minim biological reagent, it is characterized in that: distribution system is mainly by syringe pump, the 4-2 introduction valve, the reservoir pressure reagent bottle, pressure regulating system, solenoid valve, motion platform, flow sensor and intelligence operation control system are formed, the reservoir pressure reagent bottle connects the ambient pressure source by pressure regulating system, syringe pump connects syringe, motion platform is arranged on the pipe system below, flow sensor is arranged on the solenoid valve top, the 4-2 introduction valve connects the reservoir pressure reagent bottle respectively, solenoid valve and syringe, the intelligence operation control system connects the 4-2 introduction valve respectively, solenoid valve, motion platform, flow sensor and pressure regulating system.

Images