Control method and system for ultra-high performance liquid chromatography analysis

Abstract

The present application relates to a control method and system for ultra-high performance liquid chromatography analysis. The method includes: the main and auxiliary pumps infuse the system according to a preset pressure and a preset flow rate; receive a signal for preparing for injection; according to the signal for preparing for injection, the control system enters or maintains an INJECT state; calculates the compensation flow rate according to the main pump chamber plunger operation data, the preset pressure, the sampling needle volume, the set time and the preset flow rate; the control system enters a LOAD state; controls the sampling needle to be connected to the waste liquid pipe through the needle seat for pressure relief, and the syringe extracts the sample according to the set value; the control system enters a pre-pressurization state, and the main and auxiliary pumps are superimposed on the vectors and infuse the system according to the compensation flow rate; the control system enters the INJECT state again, and the flow rate after the main and auxiliary pumps are superimposed on the vectors is restored to the preset flow rate, and an analysis start signal is sent to the workstation. The use of this method can avoid the relatively large pressure drop generated at the moment after the valve is cut.

Description

Technical Field

[0001] The present application relates to the technical field of ultra-high performance liquid chromatography analysis, and in particular to a control method and system for ultra-high performance liquid chromatography analysis. Background Art

[0002] Ultra-high performance liquid chromatography (UHPLC) is gradually replacing conventional high performance liquid chromatography (HPLC) systems for separation and analysis of complex samples due to its advantages of high separation, high throughput, high sensitivity, rapid analysis and saving of mobile phase. The commonly used pressure of UHPLC is usually 40-80 MPa, and the highest can reach more than 120 MPa. If, under such system pressure conditions, a sample at normal pressure is introduced into the UHPLC system using a traditional injection valve, on the one hand, a portion of the input mobile phase will be used to compensate for the compression of the normal pressure sample, compressing the sample to the system pressure. Therefore, the actual output flow rate will be much smaller than the flow rate before injection, causing the system to produce a relatively large pressure drop at the moment after the valve is cut. The large pressure drop in a short period of time will impact the chromatographic column, causing the column head packing to collapse, seriously affecting the separation effect and service life of the chromatographic column; on the other hand, the high-pressure liquid will actively flow to the low-pressure side. At the moment the normal pressure sample enters the high-pressure system, the liquid will actively flow into the sample, which is opposite to the flow direction of the sample entering the system, thereby increasing the diffusion of the sample in the pipeline, resulting in an increase in the theoretical plate height during sample analysis, a decrease in the overall theoretical plate number, an increase in peak broadening, and a decrease in column efficiency, thereby losing some of the performance advantages of the UHPLC system.

[0003] At present, there are methods to pressurize the system by using multiple high-pressure rotary switching valves, such as patent number US8257586B2, which uses two high-pressure rotary switching valves to change the flow path and extend the valve cutting time. During the valve cutting process, a high-pressure pump is used to pressurize the sample, and then the pressurized sample is introduced into the system. This method requires two high-pressure valves, which need to be switched under high pressure and low pressure conditions, and their lifespan is much lower than that of normal pressure components. Increasing the number of high-pressure valves will increase the maintenance cost, maintenance frequency and maintenance difficulty of the system during use. In addition, using the infusion flow path to pressurize the sample requires extending the valve cutting time. During this process, the infusion flow path is completely disconnected from the chromatographic column, which is equivalent to the real-time flow rate of the chromatographic column being 0 during the process of pressurizing the sample. Therefore, although this method reduces the pressure drop caused by the introduction of the sample into the system, it also increases the pressure drop of the chromatographic column during the valve cutting process. In fact, the pressure sudden change on the column head still exists.

[0004] In addition, there is also a method of adding a high-pressure metering pump to the system flow path to pressurize the sample, such as patent number US9435773B2, which uses a high-pressure metering pump, which is in the system flow path. After sampling, the sample is first pressurized using the high-pressure metering pump, and then the sample is introduced into the system. This method requires adding a high-pressure metering pump in the system flow path, that is, a relatively complex mobile phase will flow through the metering pump (such as a buffer salt solution of a certain concentration), and the high-pressure metering pump does not have a separate cleaning pump and cleaning liquid flow path to clean itself. There is a certain probability of precipitating buffer salts when the sample is inhaled, which will shorten the life of the high-pressure metering pump and increase its maintenance difficulty. In addition, the metering pump is in the system, that is, it is part of the system hysteresis volume, and its volume is at least the maximum injection volume of the system (actually, due to the existence of sealing components, plunger gaps, travel margins, etc., the volume will be larger), which will greatly increase the hysteresis volume of the system, that is, increase the time for the gradient ratio change to reach the chromatographic column head when the gradient is running. The peak elution time of UHPLC is very fast. The increase in dwell volume caused by this method may cause the chromatographic peak to be eluted before the gradient change reaches the column head, limiting the application of fast gradient changes.

[0005] In conclusion, the existing ultra-high performance liquid chromatography system will bring other problems while solving the pressure problem. Therefore, there is an urgent need for a control method for ultra-high performance liquid chromatography analysis that can reduce the impact of pressure shock on the chromatographic column and has low cost. Summary of the invention

[0006] Based on this, it is necessary to provide a control method and system for ultra-high performance liquid chromatography analysis that can reduce the pressure change of the chromatographic column during the injection process in order to solve the above technical problems.

[0007] A control method for ultra-high performance liquid chromatography analysis, the method comprising:

[0008] The main and auxiliary pumps deliver fluid to the system at a preset pressure and preset flow rate;

[0009] receiving a signal for preparing to inject a sample;

[0010] According to the injection preparation signal, the control system enters or maintains the INJECT state;

[0011] Calculate the compensation flow rate according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow rate;

[0012] The control system enters the LOAD state;

[0013] The sampling needle is controlled to be connected to the waste liquid tube through the needle seat for pressure relief, and the syringe extracts the sample according to the set value;

[0014] The control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed on each other and the fluid is infused into the system according to the compensation flow rate;

[0015] The control system enters the INJECT state again, the flow rate after the main and auxiliary pump vector superposition is restored to the preset flow rate, and an analysis start signal is sent to the workstation.

[0016] In one of the embodiments, before the main and auxiliary pumps infuse fluid into the system according to the preset pressure and preset flow rate, the method further includes: obtaining the preset pressure and the preset flow rate.

[0017] In one of the embodiments, the compensation flow is calculated according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow, including: when the system is an isocratic system, obtaining the plunger operation distance of the main pump chamber in the process of compressing the mobile phase from normal pressure to the preset pressure; calculating the first liquid volume required to compress the liquid in the main pump chamber from normal pressure to the preset pressure according to the plunger operation distance and the plunger diameter; obtaining the sampling needle volume and the main pump chamber volume; calculating the second liquid volume required to compress the normal pressure liquid in the sampling needle to the preset pressure according to the main pump chamber volume, the first liquid volume and the sampling needle volume; calculating the flow increase value according to the second liquid volume and the set time; calculating the sum of the preset flow and the flow increase value to obtain the compensation flow;

[0018] The control system enters a pre-pressurization state, and the main and auxiliary pumps are superimposed and infuse fluid into the system according to the compensation flow rate, including: the control system enters a pre-pressurization state, and the main and auxiliary pumps are superimposed and infuse fluid into the system according to the compensation flow rate, and continue for a set time.

[0019] In one of the embodiments, the compensation flow is calculated according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow, including: when the system is a high-pressure gradient system, obtaining the plunger operation distance of each main pump chamber in the process of compressing the mobile phase from normal pressure to the preset pressure and the flow ratio of each channel; calculating the first liquid volume required for compressing the liquid from normal pressure to the preset pressure according to the plunger operation distance of each channel, the flow ratio of each channel and the plunger diameter; obtaining the sampling needle volume and the pump chamber volume; calculating the second liquid volume required for compressing the normal pressure liquid in the sampling needle to the preset pressure according to the pump chamber volume, the first liquid volume and the sampling needle volume; calculating the flow increase value according to the second liquid volume and the set time; calculating the sum of the preset flow and the flow increase value to obtain the compensation flow;

[0020] The control system enters a pre-pressurization state, and the main and auxiliary pumps are superimposed to infuse fluid into the system at a compensation flow rate, including: the control system enters a pre-pressurization state, and the main and auxiliary pumps are superimposed to infuse fluid into the system at a compensation flow rate for a set period of time.

[0021] In one of the embodiments, the control system enters a pre-pressurization state, and the main and auxiliary pumps are vector-superimposed and then infuse fluid into the system at a compensation flow rate, including: the control system enters a pre-pressurization state; when the system is a high-pressure gradient system, the flow ratio of the first route is obtained; the real-time system pressure and the real-time system flow rate are obtained; the pressure difference is obtained according to the difference between the preset pressure and the real-time system pressure; the flow difference is calculated according to the difference between the preset flow rate and the real-time system flow rate; the flow rate is increased according to the pressure difference and the flow difference to obtain the compensation flow rate to infuse fluid into the system, forming a closed-loop control, and when the pressure difference is greater than or equal to the margin value, the fluid is infused into the system at the preset flow rate; wherein, the real-time system flow rate is less than the flow threshold, and the margin value is a negative number.

[0022] In one embodiment, before controlling the sampling needle to release pressure through the needle seat and connecting to the waste liquid pipe, the method includes: controlling the syringe to empty and absorb the injection liquid.

[0023] In one of the embodiments, the sampling needle is controlled to be connected to the waste liquid pipe through the needle seat for pressure relief, and the syringe extracts samples according to the set value, including: controlling one end of the sampling needle to be connected to the syringe through the sixth valve port and the fifth valve port of the six-way rotary switching valve, and the other end to be connected to the waste liquid pipe through the needle seat, the third valve port and the fourth valve port of the six-way rotary switching valve; controlling the syringe to empty the injection liquid into the sampling needle to control the sampling needle for pressure relief; controlling the sampling needle to move to the cleaning seat for cleaning; controlling the sampling needle to move to the sample position to extract samples according to the set value; controlling the sampling needle to move to the cleaning seat for cleaning again, and moving to the needle seat for sealing.

[0024] A control system for ultra-high performance liquid chromatography analysis, comprising:

[0025] Infusion module, used for main and auxiliary pumps to infuse fluid into the system according to preset pressure and preset flow rate;

[0026] A sample preparation signal receiving module, used for receiving a sample preparation signal;

[0027] A state adjustment module, used to control the system to enter or maintain the INJECT state according to a signal for preparing for injection;

[0028] A compensation flow calculation module, used to calculate the compensation flow according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow;

[0029] The state adjustment module is used to control the system to enter the LOAD state;

[0030] A pressure relief module, used to control the sampling needle to be connected to the waste liquid pipe through the needle seat for pressure relief;

[0031] A sample extraction module is used to extract samples according to set values;

[0032] The state adjustment module is used to control the system to enter the pre-pressurization state, and the main and auxiliary pumps are superimposed on each other to infuse the system with liquid according to the compensation flow rate;

[0033] The analysis start signal sending module is used to control the system to enter the INJECT state again, the flow rate after the main and auxiliary pump vectors are superimposed is restored to the preset flow rate, and an analysis start signal is sent to the workstation.

[0034] In one embodiment, a control system for ultra-high performance liquid chromatography analysis further includes: a syringe aspiration module, which is used to control the emptying of the syringe and aspiration of the injection liquid.

[0035] An ultra-high performance liquid chromatography analysis system controlled by the above-mentioned ultra-high performance liquid chromatography analysis control method comprises: an ultra-high performance liquid chromatography infusion device and an ultra-high performance liquid chromatography automatic injection device; the ultra-high performance liquid chromatography infusion device comprises a main pump, an auxiliary pump, inlet and outlet one-way valves, a main pump cavity pressure sensor and a system pressure sensor; an ultra-high performance liquid chromatography automatic injection device, the ultra-high performance liquid chromatography automatic injection device comprises a sampling device, a cleaning device, a waste liquid flow path, a syringe and a two-position three-way valve and a six-way rotary switching valve, the stator of the six-way rotary switching valve is provided with a first groove connected to a mobile phase inlet valve port, and the first groove is located at a circumferential position where the mobile phase inlet valve port is located.

[0036] The above-mentioned control method and system for ultra-high performance liquid chromatography analysis pre-pressurizes the sample during the pre-pressurization process through an infusion pump, compensates for the pressure difference caused by the normal pressure sample entering the high-pressure system during the injection process, avoids the relatively large pressure drop generated at the moment when the valve is cut and the sample enters the system in the prior art, thereby avoiding the collapse of the chromatographic column head filler, optimizing the separation effect of the chromatographic column and increasing the service life of the chromatographic column, and also avoids the high-pressure flow after the valve is cut. Reverse influx into the sample flow path causes sample diffusion and reduced column efficiency; and the sample in the sampling needle is pressurized in the pre-pressurized state, and the pressurized sample directly enters the chromatographic column. The sample does not pass through other positions of the system flow path, and the system flow path does not need to be cleaned, reducing the cleaning difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic flow chart of a control method for ultra-high performance liquid chromatography analysis in one embodiment;

[0038] Figure 2 A system structure diagram of an isocratic ultra-high performance liquid chromatography analysis system in an INJECT state in an embodiment;

[0039] Figure 3 A system structure diagram of an isocratic ultra-high performance liquid chromatography analysis system in a LOAD state in one embodiment;

[0040] Figure 4 It is a system structure diagram of an isocratic ultra-high performance liquid chromatography analysis system in a pre-pressurized state in one embodiment;

[0041] Figure 5 A system structure diagram of a high-pressure gradient ultra-high performance liquid chromatography analysis system in an INJECT state in an embodiment;

[0042] Figure 6 A schematic diagram of the structure of a stator of a six-way rotary switching valve in an ultra-high performance liquid chromatography analysis system in one embodiment;

[0043] Figure 7 A schematic diagram of the structure of a six-way rotary switching valve rotor in an ultra-high performance liquid chromatography analysis system in one embodiment;

[0044] Figure 8 It is a structural block diagram of a control system for ultra-high performance liquid chromatography analysis in one embodiment.

[0045] Figures are labeled: six-way rotary switching valve 110; stator 101; first valve port 111; second valve port 112; third valve port 113; fourth valve port 114; fifth valve port 115; sixth valve port 116; first notch 117; rotor 102; second notch 1011; third notch 1012; fourth notch 1013; system pressure sensor 103; sampling needle 120; needle seat 130; waste liquid flow path 140; syringe two-position three-way valve 150 ; Syringe 160; Sampling needle cleaning device 170; Cleaning seat 171; Cleaning pump 172; Controller 180; Sample bottle 190; First main piston pump 210; First main pump chamber 211; First main pump chamber pressure sensor 212; First auxiliary piston pump 220; Second main piston pump 230; Second main pump chamber 231; Second main pump chamber pressure sensor 232; Second auxiliary piston pump 240; Chromatographic column 300; Detector 400; Workstation 500. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0047] In one embodiment, Figure 1 As shown, a control method for ultra-high performance liquid chromatography analysis is provided, comprising the following steps:

[0048] S110, the main pump and the auxiliary pump infuse fluid into the system according to the preset pressure and preset flow rate.

[0049] Among them, after the main pump chamber completes the liquid aspiration, the main pump chamber motor speed is changed according to the real-time pressure of the main pump chamber pressure sensor to form a closed-loop control until the mobile phase at normal pressure in the main pump chamber is compressed to the preset pressure. The main pump chamber controls the infusion of the mobile phase that has reached the system pressure, and the auxiliary pump chamber aspirates liquid. After the main and auxiliary pump vectors are superimposed, the preset flow rate is reached to infuse liquid into the system.

[0050] Wherein, when the system is an isocratic system, the main pump chamber may be the first main pump chamber 211; when the system is a high-pressure gradient system, the main pump chamber may be the first main pump chamber 211 or the second main pump chamber 231. Of course, when the system is an isocratic system, the main pump chamber pressure sensor may be the first main pump chamber pressure sensor 212; when the system is a high-pressure gradient system, the main pump chamber pressure sensor may be the first main pump chamber pressure sensor 212 or the second main pump chamber pressure sensor 232.

[0051] After the main pump chamber completes the aspiration, the controller changes the main pump chamber motor speed according to the real-time pressure of the main pump chamber pressure sensor to form a closed-loop control until the mobile phase at normal pressure in the main pump chamber is compressed to the system pressure P1. The distance L that the plunger travels during this process is recorded, and the L value is updated once per infusion pump cycle, replacing the information of the old cycle with the information of the new cycle.

[0052] Among them, when the system is an isocratic system, such as Figure 2-Figure 4 As shown, the infusion unit is composed of two plunger pumps that are driven separately in series. The first main plunger pump 210 is provided with a first main pump chamber pressure sensor 212 for real-time monitoring of the pressure of the first main pump chamber 211. The first main pump chamber pressure sensor 212 is responsible for transmitting the real-time pressure signal to the controller 180. The controller 180 controls the operation of the first main plunger pump 210 and the first auxiliary plunger pump 220 by controlling the driver of the plunger pump. A one-way valve is installed at the inlet and outlet of the first main pump chamber 211, respectively, so that the liquid can only flow from one side of the first main pump chamber 211 to the other side of the first auxiliary plunger pump 220.

[0053] When the pressure in the first main pump chamber 211 is less than the system pressure, the outlet check valve is closed, and the liquid in the first main pump chamber 211 is completely isolated from the system. At this time, the controller 180 controls the first auxiliary plunger pump 220 to output a preset flow rate; when the pressure in the first main pump chamber 211 is greater than the system pressure, the outlet check valve is opened, and the controller 180 controls the first auxiliary plunger pump 220 to aspirate liquid, and the first main plunger pump 210 to output a mobile phase that is the sum of the aspirated flow rate of the first auxiliary plunger pump 220 and the preset flow rate. Among them, the volume V0 in the first main pump chamber 211 is known during the design (unit μL) and can be obtained by measurement or theoretical calculation of drawings. After the mobile phase flows out of the infusion system, it enters the six-way rotary switching valve 110 of the automatic sampler. The main and auxiliary pump vectors are superimposed as the sum of the flow vector values ​​of the main pump and the auxiliary pump, where infusion is recorded as a positive value and aspiration is recorded as a negative value.

[0054] S120, receiving a sample injection preparation signal.

[0055] The sample injection preparation signal may be sent by the workstation 500 .

[0056] S130, according to the injection preparation signal, the control system enters or maintains the INJECT state.

[0057] Among them, Figure 2 and Figure 5 As shown, the system enters the INJECT state, the fourth groove 1013 of the rotor 102 of the six-way rotary switching valve 110 connects the first valve port 111 and the sixth valve port 116 of the stator 101, the second groove 1011 connects the second valve port 112 and the third valve port 113, and the third groove 1012 connects the fourth valve port 114 and the fifth valve port 115.

[0058] At this time, the sampling needle 120 is located in the needle seat 130, and the two are completely sealed. The mobile phase output by the infusion pump passes through the first valve port 111 and enters the sixth valve port 116, flows through the sampling needle 120 and the needle seat 130, enters the third valve port 113 of the valve, and finally flows out from the second valve port 112 and enters the chromatographic column 300. At this time, the drainage cleaning time of the syringe 160 is set to discharge the bubbles in the syringe 160.

[0059] S140, calculating the compensation flow rate according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow rate.

[0060] The infusion pump is a reciprocating series pump, which basically consists of two states:

[0061] 1) The auxiliary pump delivers liquid at the set flow rate (at this time, the one-way valve is closed to separate the two pump flow paths, and the main pump completes the liquid suction and pressurization);

[0062] 2) The one-way valve is opened to connect the two pumps, the auxiliary pump sucks liquid, and the main pump infuses liquid; the main pump infusion speed = auxiliary pump suction flow (absolute value) + system set flow.

[0063] Therefore, the compensation flow can occur in state 1 or state 2).

[0064] S150, the control system enters the LOAD state.

[0065] Among them, Figure 3 As shown, the system enters the LOAD state, the second groove 1011 of the rotor 102 of the six-way rotary switching valve 110 connects the first valve port 111 and the second valve port 112 of the stator 101, the third groove 1012 connects the third valve port 113 and the fourth valve port 114, and the fourth groove 114 connects the fifth valve port 115 and the sixth valve port 116.

[0066] Specifically, the system enters the LOAD state from the INJECT state, and the rotor 102 rotates 60° counterclockwise. During the switching process, the angle of the chromatographic column 300 to cut off the flow is α. After switching to the LOAD state, the liquid with system pressure in the sampling needle 120 will release excess pressure from the waste liquid port connected to the waste liquid flow path 140 through the fourth valve port 114. In this state, the syringe 160 is connected to the fifth valve port 115 of the six-way rotary switching valve 110 through the syringe two-position three-way valve 150, and then connected to the sampling needle 120 through the sixth valve port 116.

[0067] S160, controlling the sampling needle to be connected to the waste liquid pipe through the needle seat to release the pressure, and the syringe extracts the sample according to the set value.

[0068] Among them, Figure 3 As shown, the sample can be stored in the sample bottle 190 in advance, and the sampling needle 120 is inserted into the sample bottle 190 to extract the sample. The syringe, the sampling needle, the needle seat, and the waste liquid pipe are connected in sequence, and the minimum pressure is in the waste liquid pipe, and the pressure is released from the waste liquid pipe.

[0069] S170, the control system enters the pre-pressurization state, and the main and auxiliary pumps are vector-superimposed and fluid is infused into the system according to the compensation flow rate.

[0070] Among them, Figure 4 As shown, the system enters the pre-pressurization state from the LOAD state, and the rotor rotates counterclockwise by an angle of α. In the PRE state, the infusion pump, the sampling needle 120, the needle seat 130, and the chromatographic column 300 are all in the same flow path, and the chromatographic column 300 will not be interrupted. The system can switch to the pre-pressurization state and stay for a period of time, because the series plunger pump has been running, and the chromatographic column 300 and the sampling needle 120 are in the same flow path. At this time, the system fluid will actively pressurize the sample in the sampling needle 120. The volume of the sample taken by the sampling needle 120 is generally half of the volume of the sampling needle, so in this state, the sample is in the front end of the sampling needle 120, the needle seat 130 and the third valve port 113, and no additional diffusion will occur. The injection system waits for a certain period of time in pre-pressurization, such as 0.1s, and switches to the INJECT state after the sample is pressurized. At this time, the sample pressure entering the chromatographic column 300 is consistent with the system pressure, and will not cause reverse diffusion due to the pressure difference between the sample and the system.

[0071] S180, the control system enters the INJECT state again, the flow rate after the main and auxiliary pump vectors are superimposed is restored to the preset flow rate, and an analysis start signal is sent to the workstation.

[0072] The specific position of S140 in the steps is not limited, as long as S140 is before S170.

[0073] The above-mentioned control method for ultra-high performance liquid chromatography analysis pre-pressurizes the sample during the pre-pressurization process through an infusion pump, compensates for the pressure difference caused by the normal pressure sample entering the high-pressure system during the injection process, avoids the relatively large pressure drop generated at the moment of valve cutting in the prior art, thereby avoiding the collapse of the chromatographic column head filler, optimizing the separation effect of the chromatographic column and increasing the service life of the chromatographic column, and also avoids the high-pressure flow after the valve is cut. Reverse influx into the sample flow path causes sample diffusion and reduced column efficiency; and the sample in the sampling needle is pressurized in the pre-pressurized state, and the pressurized sample directly enters the chromatographic column, the sample does not pass through other positions of the system flow path, and the system flow path does not need to be cleaned, reducing the cleaning difficulty.

[0074] In one of the embodiments, before the main and auxiliary pumps infuse fluid into the system according to the preset pressure and preset flow rate, the method further includes: obtaining the preset pressure and the preset flow rate.

[0075] The preset pressure P0 is set according to the mobile phase pressure required for chromatographic column analysis, and the preset flow rate Q0 is set according to the flow rate of the mobile phase required by the system.

[0076] In one embodiment, the compensation flow is calculated according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow, including: when the system is an isocratic system, the plunger operation distance L of the main pump chamber in the process of compressing the mobile phase from normal pressure to the preset pressure is obtained; the first liquid volume V1 required to compress the liquid in the main pump chamber from normal pressure to the preset pressure P1 is calculated according to the plunger operation distance L and the plunger diameter D: the sampling needle volume V2 and the main pump chamber volume V0 are obtained; the second liquid volume V3 required to compress the normal pressure liquid in the sampling needle to the preset pressure P1 is calculated according to the main pump chamber volume V0, the first liquid volume V1 and the sampling needle volume V2; the flow increase value is calculated according to the second liquid volume V3 and the set time; the sum of the preset flow and the flow increase value is calculated to obtain the compensation flow. The control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed and the system is infused according to the compensation flow, including: the control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed and the system is infused according to the compensation flow, and it lasts for the set time.

[0077] Among them, the control system enters a pre-pressurization state, and the main and auxiliary pumps are superimposed and infuse fluid into the system according to the compensation flow rate, including: the control system enters a pre-pressurization state, and the main and auxiliary pumps are superimposed and infuse fluid into the system according to the compensation flow rate, and continue for a set time.

[0078] Specifically, the formula for calculating the first liquid volume V1 required to compress the liquid in the main pump chamber from normal pressure to the preset pressure P1 is as follows based on the plunger running distance L and the plunger diameter D:

[0079]

[0080] The formula for calculating the second liquid volume V3 required to compress the normal pressure liquid in the sampling needle to the preset pressure P1 according to the main pump chamber volume V0, the first liquid volume V1 and the sampling needle volume V2 is as follows:

[0081]

[0082] The flow rate increase value Q1 is calculated according to the second liquid volume V3 and the set time t as follows: Q1 = V3 / t, wherein the set time may be 0.1 s.

[0083] In a specific embodiment, taking the second liquid volume V3=5μL as an example, if the system flow rate is 200μL / min, it takes 0.025min, or 1.5s, to compress the liquid pressure in the sampling needle to the system pressure. During this period, while replenishing the sampling needle pressure, it will also affect the system pressure, and the chromatographic column will have a more obvious pressure drop. At this time, the cooperation of the infusion system is required to perform pressure compensation and reduce the impact of the pressure drop on the chromatographic column. From the calculation results, it can be seen that in order to reduce the pressure drop caused by the sample in the sampling needle, it is necessary to increase the infusion volume of the second liquid volume V3 in a short period of time. If the infusion volume is increased by 5μL within 100ms, 5μL / 0.1s=50μL / min, when the six-way rotary switching valve is switched to the pre-pressurized state, the output flow of the infusion unit increases from 200μL / min to 250μL / min, maintains 100ms, and then returns to 200μL / min, and the synchronization signal is controlled by the controller. The actual infusion pump motor acceleration takes time, so it can also be considered that it linearly accelerates from 200μL / min to 250μL / min within 10ms after the valve is cut, maintains for 90ms, and then linearly decelerates from 250μL / min to 200μL / min in 10ms, with a total time of 110ms. Therefore, the set time can be 0.11s.

[0084] In one embodiment, the compensation flow is calculated according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow, including: when the system is a high-pressure gradient system, the plunger operation distance of each main pump chamber in the process of compressing the mobile phase from normal pressure to the preset pressure and the flow ratio of each channel are obtained; the first liquid volume V1 required for the liquid to be compressed from normal pressure to the preset pressure P1 is calculated according to the plunger operation distance of each channel, the flow ratio of each channel and the plunger diameter D: the sampling needle volume V2 and the pump chamber volume V0 are obtained; the second liquid volume V3 required for the normal pressure liquid in the sampling needle to be compressed to the preset pressure P1 is calculated according to the pump chamber volume V0, the first liquid volume V1 and the sampling needle volume V2; the flow increase value is calculated according to the second liquid volume V3 and the set time; the sum of the preset flow and the flow increase value is calculated to obtain the compensation flow. The control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed and the system is infused according to the compensation flow, including: the control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed and the compensation flow is reached to infuse the system, and it lasts for the set time.

[0085] Specifically, Figure 5 As shown, two series-connected plunger pumps are provided, wherein the first main plunger pump 210 and the first auxiliary plunger pump 220 form a route A, and the second main plunger pump 230 and the second auxiliary plunger pump 240 form a route B. The flow rate ratio of route A is x, and the plunger running distance of route A is L. A , the flow ratio of route B is 1-x, and the running distance of the plunger in route B is L B The formula for calculating the first liquid volume V1 required to compress the liquid from normal pressure to the preset pressure P1 is as follows based on the plunger running distance of each path, the flow ratio of each path and the plunger diameter D:

[0086]

[0087] In this embodiment, the calculation formula of the second liquid volume V3 and the flow rate increase value Q1 is the same as that of the above embodiment. At this time, the flow rate of the A channel is controlled to increase by xQ1 to infuse the system, and the flow rate of the B channel is controlled to increase by (1-x)Q1 to infuse the system, and the flow rate continues for a set time. The set time can be 0.1s.

[0088] In one of the embodiments, the control system enters a pre-pressurization state, and the main and auxiliary pumps are vector-superimposed and then infuse fluid into the system at a compensation flow rate, including: when the system is a high-pressure gradient system, obtaining the flow ratio x of the first route; obtaining the real-time system pressure P and the real-time system flow Q; obtaining the pressure difference ΔP based on the difference between the preset pressure P0 and the real-time system pressure P; calculating the flow difference ΔQ based on the difference between the preset flow Q0 and the real-time system flow Q; increasing the flow based on the pressure difference ΔP and the flow difference ΔQ to obtain a compensation flow rate to infuse fluid into the system, forming a closed-loop control, and when the pressure difference ΔP is greater than or equal to the margin value, infusing fluid into the system at the preset flow rate; wherein, the real-time system flow Q is less than the flow threshold, and the margin value is a negative number.

[0089] Among them, Figure 2 As shown, when the pressure difference ΔP is less than the margin value, the real-time flow rate Q = (Q0+ΔQ), and the control is carried out at intervals of 1 ms. The flow rate is increased according to the pressure difference ΔP and the flow difference ΔQ to obtain a compensating flow rate to infuse the system, forming a closed-loop control until the pressure difference ΔP is greater than or equal to the margin value, and the infusion to the system is restored according to the preset flow rate.

[0090] Among them, Figure 5 As shown, the first main plunger pump 210 and the first auxiliary plunger pump 220 form a route A (i.e., the first route), the second main plunger pump 230 and the second auxiliary plunger pump 240 form a route B, the flow rate ratio of route A is x, the flow rate ratio of route B is 1-x, and the real-time flow rate of route A is Q A =x(Q0+ΔQ), the real-time flow rate of road B is Q B =(1-x)(Q0+ΔQ), the margin value is -0.1Mpa, and the flow is increased according to the pressure difference ΔP and the flow difference ΔQ to obtain the compensation flow to infuse the system, forming a closed-loop control until the pressure difference ΔP is greater than or equal to the margin value, and the system is restored to infuse the fluid according to the preset flow, that is, the flow output from route A to the system is restored to xQ0, and the flow output from route B to the system is restored to (1-x)Q0.

[0091] In one embodiment, before controlling the sampling needle to release pressure through the needle seat and connecting to the waste liquid pipe, the method includes: controlling the syringe to empty and absorb the injection liquid.

[0092] Among them, controlling the syringe to empty and absorb the injection liquid includes: judging whether the drainage and cleaning time of the sampling device has been reached; if the drainage and cleaning time of the sampling device has been reached, the syringe is reset, and the six-way rotary switching valve is controlled to enter the LAOD state; if the drainage and cleaning time of the sampling device has not been reached, the two-position three-way valve of the syringe is controlled to switch to one way of injection liquid, and the syringe is controlled to absorb liquid; the two-position three-way valve of the syringe is controlled to switch to one way of the six-way rotary switching valve, and the syringe is controlled to drain and clean.

[0093] In one of the embodiments, the sampling needle is controlled to be connected to the waste liquid pipe through the needle seat for pressure relief, and the syringe extracts samples according to the set value, including: controlling one end of the sampling needle to be connected to the syringe through the sixth valve port and the fifth valve port of the six-way rotary switching valve, and the other end to be connected to the waste liquid pipe through the needle seat, the third valve port and the fourth valve port of the six-way rotary switching valve; controlling the syringe to empty the injection liquid into the sampling needle to control the sampling needle for pressure relief; controlling the sampling needle to move to the cleaning seat for cleaning; controlling the sampling needle to move to the sample position to extract samples according to the set value; controlling the sampling needle to move to the cleaning seat for cleaning again, and moving to the needle seat for sealing.

[0094] Specifically, the motor controls and moves the sampling needle 120, removes the sampling needle 120 from the needle seat 130, moves it to the position of the cleaning seat 171, and inserts it into the cleaning seat 171. The solvent selection valve of the cleaning pump 172 selects the set cleaning liquid, and according to the cleaning time set by the cleaning pump 172, the outer wall of the sampling needle is generally cleaned in the order of strong, medium, and weak. For samples that are not easy to leave residues, medium or weak cleaning liquid can be directly used; wherein, the cleaning seat 171 and the needle seat 130 can also be combined into one, and a waste liquid port and other structures can be added to the bottom of the needle seat 130. The motor controls the sampling needle 120, removes the sampling needle 120 from the cleaning seat 171, and moves it to the position of the sample bottle 190, and then the syringe extracts the sample in the sample bottle according to the set amount. Then, the motor controls the sampling needle 120 to remove the sampling needle 120 from the sample bottle 190, moves it to the position of the cleaning seat 171, and inserts it into the cleaning seat 171. The solvent selection valve of the cleaning pump 172 selects the set cleaning solution and cleans the outer wall of the sampling needle 120 in the order of strong, medium, and weak according to the set cleaning time of the cleaning pump. Finally, the motor controls the sampling needle 120 to remove the sampling needle 120 from the cleaning seat 171, moves it to the needle seat 130, and inserts it into the seal.

[0095] The cleaning pump 170 can clean the outer wall of the sampling needle 120 in the order of strong, medium and weak cleaning liquids, or can select only one or more cleaning liquids to clean the outer wall of the sampling needle 120 .

[0096] In this embodiment, during the sampling process, the sample only passes through the sampling needle 120, and the sample inside the sampling needle 120 will eventually enter the system for separation and analysis, which will affect the next needle. The only sample left is the sample on the outer wall of the sampling needle 120 during sampling. During the subsequent pre-pressurization process, only the sampling needle 120, the needle seat 130 and the third valve port 113 of the stator 101 of the six-way rotary switching valve 110 are in contact with the sample. When switching to the INJECT state, the sampling needle 120, the needle seat 130 and the third valve port 113 of the stator 101 of the six-way rotary switching valve 110 are all in the system flow path, so there is no need to clean the six-way rotary switching valve 110. Therefore, during the entire sampling process, only the outer wall of the sampling needle needs to be thoroughly cleaned to ensure low residue in the system, which reduces the cleaning cost and improves the cleaning efficiency.

[0097] In one embodiment, if Figure 6 and Figure 7 As shown, the six-way rotary switching valve 110 includes a stator 101 and a rotor 102. The stator 101 is provided with six valve ports and a first groove 117, which are the first valve port 111, the second valve port 112, the third valve port 113, the fourth valve port 114, the fifth valve port 115 and the sixth valve port 116 in sequence. The first valve port 111 is a valve port for the mobile phase to flow in. The first groove is located between the first valve port and the second valve port and is connected to the first valve port and is not connected to the second valve port. The angle between the second valve port 112 and the third valve port 113 is 60°, and the third valve port 114 is 115. The angle between the fourth valve port 114 and the fifth valve port 115 is 60°. The rotor 102 is provided with three grooves in the circumferential direction corresponding to the valve port position, namely the second groove 1011, the third groove 1012 and the fourth groove 1013. The arcs of the second groove 1011 and the third groove 1012 are both 60°. The angle between the fourth groove 1013 and the second groove 1011 is equal to the arc of the first groove 117. The sum of the arc of the fourth groove 1013, the arc of the first groove 117 and the angle between the fourth valve port 114 and the fifth valve port 115 is 180°. The sum of the arcs of the first valve port 111 and the first groove 117 is set to α, and the arc angle between the fourth groove 1013 and the third groove 1012 is set to β. Considering that the diameter of the first groove 117 in the circumferential direction is generally 3 to 5 mm, the diameter of the stator hole is generally 0.3 mm, and the circumferential angle is 3° to 11.5°, it is recommended to reserve a margin of 15°, so the preferred α∈[15°,45°] (for example, α=30°). The angle between the fourth valve port 114 and the fifth valve port 115 is β. Theoretically, the allowable value range of β is 60°>β>α. Also considering the diameter of the stator hole, a margin of 15° is reserved, β∈[α+15°,45°]. Taking α∈[15°,45°] into consideration, the value ranges of the two are α∈[15°,30°] and β∈[α+15°,45°]. Therefore, the value of β = 45° can satisfy almost all the allowed α values. Figure 7 As shown, there are three grooves of different lengths on the rotor. In addition to the two grooves with an arc length of 60°, the arc of the fourth groove 1013 is (180°-α-β). After determining that β=45°, the arc of the groove is (135°-α).

[0098] The controller 180 controls the rotor 102 to rotate, and the six-way rotary switching valve 110 can be switched among three positions: LOAD, INJECT, and pre-pressurization. In this embodiment, during the entire injection process, the chromatographic column and the infusion pump only cut off the flow by a rotation angle α when the INJECT state is switched to the LOAD state, and the chromatographic column cut-off time is short, reducing the impact of pressure shock on the chromatographic column.

[0099] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps may include multiple steps or multiple stages. These steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed in turn or alternately with other steps or at least part of the steps or stages in other steps.

[0100] In one embodiment, Figure 8 As shown, a control system for ultra-high performance liquid chromatography analysis is provided, comprising:

[0101] Infusion module 810, used for the main and auxiliary pumps to infuse the system according to the preset pressure and preset flow rate;

[0102] The sample preparation signal receiving module 820 is used to receive the sample preparation signal;

[0103] The state adjustment module 830 is used to control the system to enter or maintain the INJECT state according to the ready injection signal;

[0104] The compensation flow calculation module 840 is used to calculate the compensation flow according to the main pump chamber plunger operation data, the preset pressure, the sampling needle volume, the set time and the preset flow;

[0105] The state adjustment module 830 is used to control the system to enter the LOAD state;

[0106] The pressure relief module 850 is used to control the sampling needle to be connected to the waste liquid pipe through the needle seat to relieve pressure;

[0107] The sample extraction module 860 is used to extract samples according to the set value;

[0108] The state adjustment module 830 is used to control the system to enter the pre-pressurization state, and the main pump and the auxiliary pump vector are superimposed to infuse the system according to the compensation flow rate;

[0109] The analysis start signal sending module 870 is used to control the system to enter the INJECT state again, the flow rate after the main and auxiliary pumps are vector-superimposed is restored to the preset flow rate, and an analysis start signal is sent to the workstation.

[0110] In one of the embodiments, the control system for ultra-high performance liquid chromatography analysis further includes: a syringe aspiration module, which is used to control the emptying of the syringe and aspiration of the injection liquid.

[0111] In one of the embodiments, the control system of the ultra-high performance liquid chromatography analysis further includes: a pressure and flow data acquisition module, which is used to obtain the preset pressure P0 and the preset flow Q0 before the main and auxiliary pumps infuse the system according to the preset pressure and preset flow.

[0112] In one embodiment, the compensation flow calculation module 840 includes: a plunger running distance acquisition unit, which is used to obtain the plunger running distance of the main pump chamber when the mobile phase is compressed from normal pressure to a preset pressure when the system is an isocratic system; a first liquid volume calculation unit, which is used to calculate the first liquid volume required to compress the liquid in the main pump chamber from normal pressure to a preset pressure based on the plunger running distance and the plunger diameter; a volume acquisition unit, which is used to obtain the sampling needle volume and the main pump chamber volume; a second liquid volume calculation unit, which is used to calculate the second liquid volume required to compress the normal pressure liquid in the sampling needle to a preset pressure based on the main pump chamber volume, the first liquid volume and the sampling needle volume; a flow increase value calculation unit, which is used to calculate the flow increase value based on the second liquid volume and the set time; and a compensation flow calculation unit, which is used to calculate the sum of the preset flow and the flow increase value to obtain the compensation flow. The state adjustment module 830 is also used to control the system to enter a pre-pressurization state, and the main and auxiliary pumps are superimposed vectors to infuse the system according to the compensation flow, and continue for a set time.

[0113] In one embodiment, the compensation flow calculation module 840 includes: a plunger operation data acquisition unit, which is used to obtain the plunger operation distance and the flow ratio of each main pump chamber in the process of compressing the mobile phase from normal pressure to a preset pressure when the system is a high-pressure gradient system; a first liquid volume calculation unit, which is used to calculate the first liquid volume required for the liquid to be compressed from normal pressure to a preset pressure according to the plunger operation distance of each channel, the flow ratio of each channel and the plunger diameter; a volume acquisition unit, which is used to obtain the sampling needle volume and the pump chamber volume; a second liquid volume calculation unit, which is used to calculate the second liquid volume required for the normal pressure liquid in the sampling needle to be compressed to a preset pressure according to the pump chamber volume, the first liquid volume and the sampling needle volume; a flow increase value calculation unit, which is used to calculate the flow increase value according to the second liquid volume and the set time; a compensation flow calculation unit, which is used to calculate the sum of the preset flow and the flow increase value to obtain the compensation flow. The state adjustment module 830 is also used to control the system to enter a pre-pressurization state, and the main and auxiliary pumps are superimposed to reach the compensation flow to infuse the system, and it lasts for a set time.

[0114] In one embodiment, the state adjustment module 830 includes: an infusion control unit, which is used to control the system to enter a pre-pressurization state; a flow ratio acquisition unit of the first route, which is used to obtain the flow ratio of the first route when the system is a high-pressure gradient system; a system information acquisition unit, which is used to obtain real-time system pressure and real-time system flow; a pressure difference calculation unit, which is used to obtain the pressure difference according to the difference between the preset pressure and the real-time system pressure; a flow difference calculation unit, which is used to calculate the flow difference according to the difference between the preset flow and the real-time system flow; a system infusion control unit, which is used to increase the flow according to the pressure difference and the flow difference to obtain a compensating flow to infuse the system, forming a closed-loop control, and when the pressure difference is greater than or equal to the margin value, infuse the system according to the preset flow; wherein, the real-time system flow is less than the flow threshold, and the margin value is a negative number.

[0115] In one embodiment, the sample extraction module 860 includes: a connection unit, used to control one end of the sampling needle to be connected to the syringe through the sixth valve port and the fifth valve port of the six-way rotary switching valve, and the other end to be connected to the waste liquid pipe through the needle seat, the third valve port and the fourth valve port of the six-way rotary switching valve; a pressure relief unit, used to control the syringe to empty the injection liquid into the sampling needle, so as to control the sampling needle to relieve pressure; a cleaning unit, used to control the sampling needle to move to the cleaning seat for cleaning; a sample extraction unit, used to control the sampling needle to move to the sample position to extract the sample according to the set value; a sampling needle moving unit, used to control the sampling needle to move to the cleaning seat again for cleaning, and move to the needle seat for sealing.

[0116] For the specific definition of the control system of ultra-high performance liquid chromatography analysis, please refer to the definition of the control method of ultra-high performance liquid chromatography analysis in the above text, which will not be repeated here. Each module in the control system of the above-mentioned ultra-high performance liquid chromatography analysis can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0117] In one embodiment, an ultra-high performance liquid chromatography analysis system controlled by the control method of ultra-high performance liquid chromatography analysis described in the above embodiment is provided, including: an ultra-high performance liquid chromatography infusion device and an ultra-high performance liquid chromatography automatic sampling device; the ultra-high performance liquid chromatography infusion device includes a main pump, an auxiliary pump, inlet and outlet one-way valves, a main pump chamber pressure sensor and a system pressure sensor; an ultra-high performance liquid chromatography automatic sampling device, the ultra-high performance liquid chromatography automatic sampling device includes a sampling device, a cleaning device, a waste liquid flow path, a syringe and a two-position three-way valve and a six-way rotary switching valve, the stator of the six-way rotary switching valve is provided with a first groove connected to the mobile phase inlet valve port, and the first groove is located at the circumferential position of the mobile phase inlet valve port.

[0118] Among them, an ultra-high performance liquid chromatography automatic sampling device can be applied to HPLC system and UHPLC system, the infusion pump delivers the system mobile phase, the ultra-high performance liquid chromatography automatic sampling device automatically introduces the sample, the chromatographic column analyzes the sample, and the detector connected to the chromatographic column is responsible for detecting the sample.

[0119] The above-mentioned ultra-high performance liquid chromatography automatic sampling device, by setting a first groove in the six-way rotary switching valve, the sample inlet valve port is connected with the first groove, thereby increasing the angle of the sample flowing into the valve. During the switching process of each flow path state, the rotor rotates in a larger range to ensure the connection with other valve ports and the sample inlet valve port and the first groove, thereby reducing the system flow interruption angle; only a single six-way rotary switching valve is used to achieve switching between three states, the overall structure of the device is simple, and the pipeline connection is simple.

[0120] Among them, Figure 2-Figure 7As shown, the six-way rotary switching valve 110 includes a stator 101 and a rotor 102. The stator 101 is provided with six valve ports and a first groove 117, which are the first valve port 111, the second valve port 112, the third valve port 113, the fourth valve port 114, the fifth valve port 115 and the sixth valve port 116 in sequence. The first valve port 111 is a sample inlet valve port. The first groove position 117 is located between the first valve port 111 and the second valve port 112 and is connected to the first valve port but not connected to the second valve port. The angle between the second valve port 112 and the third valve port 113 is 60°. The angle between the third valve port 113 and the fourth valve port 114 is 60°; the rotor 102 is provided with three grooves in the circumferential direction corresponding to the valve port position, namely the second groove 1011, the third groove 1012 and the fourth groove 1013, the arc of the second groove 1011 and the third groove 1012 is 60°, the angle between the fourth groove 1013 and the second groove 1011 is equal to the arc of the first groove 117, and the sum of the arc of the fourth groove 1013, the arc of the first groove 117 and the angle between the fourth valve port 114 and the fifth valve port 115 is 180°.

[0121] Among them, the first valve port 111, the second valve port 112, the third valve port 113, the fourth valve port 114, the fifth valve port 115 and the sixth valve port 116 are non-circumferentially uniformly distributed. The second groove 1011, the third groove 1012 and the fourth groove 1013 have unequal arcs on the rotor, and the rotor 102 has three grooves of different lengths. The arcs of the second groove 1011 and the third groove 1012 are 60°, and the arc between the third groove 1012 and the fourth groove 1013 is β.

[0122] Among them, in the ultra-high performance liquid chromatography automatic sampling device, the infusion pump outlet is connected to the first valve port 111, the chromatographic column 300 is connected to the second valve port 112, the needle seat 130 is connected to the third valve port 113, the waste liquid flow path 140 is connected to the fourth valve port 114, the two-position three-way valve 150 is connected to the fifth valve port 115, and the sampling needle 120 is connected to the sixth valve port 116.

[0123] The above-mentioned ultra-high performance liquid chromatography automatic sampling device has six valve ports respectively connected to the infusion pump, the chromatographic column, the needle seat, the waste liquid flow path, the two-position three-way valve and the sampling needle, which can realize the cleaning of the ultra-high performance liquid chromatography automatic sampling device to ensure the purity of the sample, making the sample analysis more accurate.

[0124] The cleaning device 170 includes a cleaning seat 171, a cleaning pump 172 and a solvent selection valve 173. The solvent selection valve 173 can be connected to various cleaning solvents, such as strong cleaning liquid, medium cleaning liquid and weak cleaning liquid. The cleaning solvent selection valve 173 can be connected to three different cleaning solvent storage bottles. The controller 180 controls the valve position of the cleaning solvent selection valve 173, allowing the cleaning pump 172 to introduce the corresponding cleaning solvent into the cleaning seat 171 according to the set cleaning process to clean the outer wall of the sampling needle 120.

[0125] Among them, the two-position three-way valve 150 is connected to the syringe 160; when the two-position three-way valve 150 is connected to the liquid storage bottle, the syringe is communicated with the liquid storage bottle storing the injection liquid, and the syringe can absorb the injection liquid in the liquid storage bottle; when the two-position three-way valve 150 is connected to the fifth valve port 115, the syringe is communicated with the fifth valve port 115, and when the six-way rotary switching valve 110 is in the INJECT state, the syringe can push out the syringe, discharge its own air or replace the old injection liquid.

[0126] The controller 180 controls the rotor 102 to rotate, and the six-way rotary switching valve 110 can be switched at any position to reach three positions: LOAD, INJECT and PRE, wherein the PRE state is a pre-pressurized state. Figure 6-Figure 7 As shown, the thin lines represent the stator and the thick lines represent the rotor.

[0127] In one embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above method embodiments when executing the computer program.

[0128] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0129] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0130] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0131] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A control method for ultra-high performance liquid chromatography analysis, characterized in that: The method comprises: The main and auxiliary pumps infuse liquid into the system at a preset pressure and a preset flow rate; wherein the mobile phase flows out of the infusion system and enters a six-way rotary switching valve (110) of the automatic sample injector, wherein the six-way rotary switching valve (110) comprises a stator (101), wherein the stator (101) is provided with six valve ports and a first notch (117), which are the first valve port (111), the second valve port (112), the third valve port (113), the fourth valve port (114), the fifth valve port (115) and the sixth valve port (116) in sequence, and the rotor (102) is in contact with the Three grooves are arranged in the circumferential direction corresponding to the valve port position, namely a second groove (1011), a third groove (1012) and a fourth groove (1013); the arcs of the second groove (1011), the third groove (1012) and the fourth groove (1013) on the rotor are unequal; the sum of the arcs of the first valve port (111) and the first groove (117) is set to α; the arc between the third groove (1012) and the fourth groove (1013) is recorded as β, α∈[15°, 30°], β∈[α+15°, 45°]; receiving a signal for preparing to inject a sample; According to the injection preparation signal, the control system enters or maintains the INJECT state; Calculate the compensation flow rate according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow rate; The control system enters the LOAD state; The sampling needle is controlled to be connected to the waste liquid tube through the needle seat for pressure relief, and the syringe extracts the sample according to the set value; The control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed on each other and the fluid is infused into the system according to the compensation flow rate; The control system enters the INJECT state again, the flow rate after the main and auxiliary pump vector superposition is restored to the preset flow rate, and an analysis start signal is sent to the workstation.

2. The method according to claim 1, characterized in that Before the main and auxiliary pumps infuse fluid into the system according to the preset pressure and the preset flow, the method further includes: obtaining the preset pressure and the preset flow.

3. The method according to claim 1, characterized in that The method of calculating the compensation flow rate according to the main pump chamber plunger operation data, the preset pressure, the sampling needle volume, the set time and the preset flow rate includes: When the system is an isocratic system, the distance traveled by the plunger of the main pump chamber during the process of compressing the mobile phase from normal pressure to a preset pressure is obtained; Calculate the first liquid volume required to compress the liquid in the main pump chamber from normal pressure to the preset pressure based on the plunger running distance and plunger diameter: Obtain the sampling needle volume and the main pump chamber volume; Calculate the volume of the second liquid required to compress the normal pressure liquid in the sampling needle to a preset pressure according to the volume of the main pump chamber, the volume of the first liquid and the volume of the sampling needle; Calculate the flow rate increase value according to the second liquid volume and the set time; Calculate the sum of the preset flow and the flow increase value to obtain the compensation flow; The control system enters a pre-pressurization state, and the main and auxiliary pumps are vector-superimposed to infuse fluid into the system according to the compensation flow rate, including: The control system enters the pre-pressurization state. After the main and auxiliary pumps are superimposed, the system is infused with fluid according to the compensation flow rate and continues for the set time.

4. The method according to claim 1, characterized in that The method of calculating the compensation flow rate according to the main pump chamber plunger operation data, the preset pressure, the sampling needle volume, the set time and the preset flow rate includes: When the system is a high-pressure gradient system, the plunger running distance of each main pump chamber in the process of compressing the mobile phase from normal pressure to a preset pressure and the flow rate ratio of each channel are obtained; Calculate the first liquid volume required to compress the liquid from normal pressure to the preset pressure based on the plunger running distance of each channel, the flow ratio of each channel and the plunger diameter: Obtain sampling needle volume and pump chamber volume; Calculate the volume of the second liquid required to compress the normal pressure liquid in the sampling needle to a preset pressure according to the volume of the pump chamber, the volume of the first liquid and the volume of the sampling needle; Calculate the flow rate increase value according to the second liquid volume and the set time; Calculate the sum of the preset flow and the flow increase value to obtain the compensation flow; The control system enters a pre-pressurization state, and the main and auxiliary pumps are vector-superimposed to infuse fluid into the system according to the compensation flow rate, including: The control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed to achieve the compensation flow rate to infuse fluid into the system, which lasts for the set time.

5. The method according to claim 1, characterized in that The control system enters a pre-pressurization state, and the main and auxiliary pumps are vector-superimposed to infuse fluid into the system according to the compensation flow rate, including: The control system enters the pre-pressurization state, and the main and auxiliary pumps are superimposed vectorially to infuse the system with fluid at the preset pressure and preset flow rate; When the system is a high pressure gradient system, the flow ratio of the first path is obtained; Get real-time system pressure and real-time system flow; According to the difference between the preset pressure and the real-time system pressure, the pressure difference is obtained; Calculate the flow difference based on the difference between the preset flow and the real-time system flow; The flow rate is increased according to the pressure difference and the flow rate difference to obtain a compensating flow rate to infuse the system, forming a closed-loop control. When the pressure difference is greater than or equal to the margin value, the system is infused at a preset flow rate; wherein, the real-time system flow rate is less than the flow threshold, and the margin value is a negative number.

6. The method according to claim 1, characterized in that Before controlling the sampling needle to be connected to the waste liquid pipe through the needle seat for pressure relief, it includes: controlling the syringe to empty and absorb the injection liquid.

7. The method according to claim 1, characterized in that The control sampling needle is connected to the waste liquid pipe through the needle seat to release the pressure, and the syringe extracts the sample according to the set value, including: Control one end of the sampling needle to be connected to the syringe through the sixth valve port and the fifth valve port of the six-way rotary switching valve, and the other end to be connected to the waste liquid pipe through the needle seat, the third valve port and the fourth valve port of the six-way rotary switching valve; Control the syringe to empty the injection liquid into the sampling needle to control the sampling needle to release pressure; Control the sampling needle to move to the cleaning seat for cleaning; Control the sampling needle to move to the sample position and extract the sample according to the set value; The sampling needle is controlled to move to the cleaning seat for cleaning again, and then moved to the needle seat for sealing.

8. A control system for ultra-high performance liquid chromatography analysis, characterized in that: include: An infusion module is used for a main and auxiliary pump to infuse liquid into a system according to a preset pressure and a preset flow rate; wherein the mobile phase flows out of the infusion system and enters a six-way rotary switching valve (110) of an automatic sample injector, wherein the six-way rotary switching valve (110) comprises a stator (101), wherein the stator (101) is provided with six valve ports and a first notch (117), which are a first valve port (111), a second valve port (112), a third valve port (113), a fourth valve port (114), a fifth valve port (115) and a sixth valve port (116), respectively; and the rotor (102 ) three grooves are arranged in a circumferential direction corresponding to the valve port position, namely a second groove (1011), a third groove (1012) and a fourth groove (1013); the arcs of the second groove (1011), the third groove (1012) and the fourth groove (1013) on the rotor are unequal; the sum of the arcs of the first valve port (111) and the first groove (117) is set to α; the arc between the third groove (1012) and the fourth groove (1013) is recorded as β, α∈[15°,30°], β∈[α+15°,45°]; A sample preparation signal receiving module, used for receiving a sample preparation signal; A state adjustment module, used to control the system to enter or maintain the INJECT state according to a signal for preparing for injection; A compensation flow calculation module, used to calculate the compensation flow according to the main pump chamber plunger operation data, preset pressure, sampling needle volume, set time and preset flow; The state adjustment module is used to control the system to enter the LOAD state; A pressure relief module, used to control the sampling needle to be connected to the waste liquid pipe through the needle seat for pressure relief; A sample extraction module is used to extract samples according to set values; The state adjustment module is used to control the system to enter the pre-pressurization state, and the main and auxiliary pumps are superimposed on each other to infuse the system with liquid according to the compensation flow rate; The analysis start signal sending module is used to control the system to enter the INJECT state again, the flow rate after the main and auxiliary pump vectors are superimposed is restored to the preset flow rate, and an analysis start signal is sent to the workstation.

9. The system according to claim 8, characterized in that Also includes: The syringe aspiration module is used to control the emptying of the syringe and aspirate the injection liquid.

10. An ultra-high performance liquid chromatography analysis system controlled by the ultra-high performance liquid chromatography analysis control method according to any one of claims 1 to 7, characterized in that: include: Ultra-high performance liquid chromatography infusion device and ultra-high performance liquid chromatography automatic injection device; The ultra-high performance liquid chromatography infusion device comprises a main pump, an auxiliary pump, an inlet check valve, an outlet check valve, a main pump cavity pressure sensor and a system pressure sensor; An ultra-high performance liquid chromatography automatic sampling device comprises a sampling device, a cleaning device, a waste liquid flow path, a syringe, a two-position three-way valve for the syringe and a six-way rotary switching valve. The stator of the six-way rotary switching valve is provided with a first groove connected to a mobile phase inlet valve port, and the first groove is located at a circumferential position of the mobile phase inlet valve port.

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