Method for mixing sample liquid by in-vitro diagnostic instrument sampling needle and application thereof
By retaining surplus reagent in the sampling needle of the in vitro diagnostic instrument and optimizing the aspiration and expulsion process, the problem of unstable test results caused by sample solution mixing methods has been solved, achieving higher test repeatability and accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHENZHEN COMEN MEDICAL INSTR
- Filing Date
- 2023-03-24
- Publication Date
- 2026-06-30
AI Technical Summary
When existing in vitro diagnostic instruments detect the content of specific proteins, the mixing method of the sample solution leads to poor repeatability of the test results, and the contact between purified water and the mixture causes unstable protein concentration.
The process employs aspiration, initial drainage, and aspiration-expulsion mixing steps. By retaining excess reagent in the liquid path and forming an isolation gas column, the aspiration-expulsion coefficient and needle tip position are optimized to prevent the purified water from mixing with the mixture and ensure the stability of the mixture.
It improved the stability of protein concentration in the sample solution, reduced the coefficient of variation in multiple parallel measurements, and improved the repeatability and accuracy of the test results.
Smart Images
Figure CN116338220B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of medical testing technology, specifically to a method and application of mixing sample solution with a sampling needle of an in vitro diagnostic instrument. Background Technology
[0002] In clinical practice, various in vitro diagnostic instruments are used to detect human samples such as blood and body fluids to obtain clinical diagnostic information. For example, in vitro diagnostic instruments such as chemical analyzers and chemiluminescence analyzers require precise sampling of liquids such as samples and analytical reagents. High-concentration samples are injected into reaction vessels and diluted and mixed to avoid affecting the test results and facilitate instrument testing and analysis. For example, when using a specific protein analyzer to measure the content of a specific protein (such as C-reactive protein) in blood in a single test, two mixing actions are required. The first mixing involves mixing the sample and a lysing agent (diluent) to obtain a diluted sample solution, the purpose of which is to dissolve the specific protein in the blood with the lysing agent to fully release the specific protein. The second mixing involves mixing the diluted sample solution, buffer solution, and latex to obtain the test sample solution, where the specific protein reacts and binds with the latex to form larger microclusters. Transmission or turbidimetric methods are usually used to detect the test sample solution. By monitoring the rate of change of the transmission or scattering signal of the microclusters after irradiation with light of a specific wavelength, the content of the specific protein in the blood sample is obtained through a specific algorithm.
[0003] Currently, when measuring the content of a specific protein in a sample solution using a specific protein analyzer, regardless of whether it is a single or double mixing, the sample solution mixing method typically includes sampling needle aspiration, initial drainage, and aspiration-expelling mixing steps. For example, in the first mixing, the sampling needle first aspirates a quantitative hemolysin, then collects a blood sample. The sampling needle then moves with the motor into the primary mixing reaction vessel, where a plunger pump uses piston motion to expel all the hemolysin and blood sample, forming a turbid liquid in the reaction vessel. The sampling needle then repeatedly aspirates and expels this turbid liquid to obtain a diluted sample solution. However, because the syringe's internal fluid path is filled with purified water, this water may enter the mixed solution during the initial drainage and aspiration-expelling mixing processes, affecting the detection results. This results in poor repeatability of the detection results obtained using existing sample solution mixing methods. Summary of the Invention
[0004] Therefore, the technical problem to be solved by the present invention is to overcome the poor repeatability of detection results of in vitro diagnostic instruments such as specific protein analyzers in the prior art, thereby providing a method and application for mixing sample solution with sampling needle of in vitro diagnostic instrument to solve the above-mentioned technical problem.
[0005] The technical solution of the present invention:
[0006] A method for mixing sample solution with a sampling needle of an in vitro diagnostic instrument includes sequential steps of aspiration, initial drainage, and aspiration / distraction mixing.
[0007] The liquid aspiration step is as follows: reagents and samples are sequentially aspirated through the sampling needle of the in vitro diagnostic instrument to sequentially form a liquid distribution of purified water, surplus reagent, reagent to be mixed and sample in the liquid path inside the needle;
[0008] The initial drainage step is as follows: after the aspiration is completed, the sample and the reagent to be mixed in the sampling needle are completely discharged into the mixing reaction container to form a turbid liquid with the initial discharge volume, and the excess reagent is retained in the liquid path;
[0009] The aspiration and mixing step is as follows: after the initial drainage is completed, a portion of the turbid liquid is aspirated through the sampling needle and then discharged into the mixing reaction container for at least one reciprocating aspiration and mixing step to obtain the sample liquid.
[0010] The liquid aspiration step also includes a first step of aspirating air before the sampling needle aspirates the reagent. After the liquid aspiration is completed, a liquid distribution of purified water, isolation air column, surplus reagent, reagent to be mixed and sample is formed in sequence in the liquid path inside the needle.
[0011] During the initial drainage step, the sampling needle is placed inside the mixing reaction container at the longitudinal center of the mixing reaction container, and the position of the sampling needle tip is preset below the liquid level of the mixture formed in the mixing reaction container after the sampling needle has absorbed part of the turbid liquid during the reciprocating suction and discharge.
[0012] The mixing vessel is a reaction cup.
[0013] The in vitro diagnostic instrument is a specific protein analyzer.
[0014] The reagent is a hemolytic agent, the sample is the original sample, the sample solution is a diluted sample solution, and the volume of the aspirated liquid in the aspiration and vomiting mixing step is 0.5 to 0.6 times the initial vomiting volume (i.e., the aspiration and vomiting coefficient of one mixing step is 0.5-0.6), preferably 0.56.
[0015] The reagent consists of buffer solution and latex, the surplus reagent is surplus buffer solution, the sample is a diluted sample, the sample solution is the sample solution to be tested, and the volume of liquid aspirated and expelled during the aspiration and expulsion mixing of the sampling needle is 0.56 to 0.62 times the volume expelled initially (i.e., the aspiration and expulsion coefficient of the secondary mixing is 0.56-0.62), preferably 0.59 times.
[0016] In the inhalation and mixing step, the amount of liquid expelled in the last cycle is less than the amount of liquid inhaled each time; preferably, the amount of liquid expelled in the last cycle is 3-10 μL less than the amount of liquid inhaled each time.
[0017] The volume of the surplus reagent in the aspirate solution is 5-15 μL.
[0018] The amount of gas inhaled to form the isolation column is 10-20 μL; preferably 15 μL.
[0019] The liquid aspiration step further includes a second air aspiration step after the sampling needle aspirates the sample, so as to form a leak-proof air column below the sample; preferably, the amount of air aspirated in the second aspiration is 3-7 μL, more preferably 5 μL.
[0020] The method described is applied in in vitro diagnostic instrument detection and analysis.
[0021] The application of the method in detecting the content of a specific protein in a sample using a specific protein analyzer includes the following steps:
[0022] The hemolysing agent and the original sample are sequentially aspirated through a sampling needle of a specific protein analyzer to form a liquid distribution of purified water, surplus hemolysing agent, hemolysing agent to be mixed, and the original sample in sequence within the needle's internal liquid path. After aspiration, the original sample and hemolysing agent to be mixed are completely expelled from the sampling needle into a primary mixing reaction container to form a turbid liquid, while the surplus hemolysing agent remains in the liquid path. After the initial expulsion, a portion of the turbid liquid is aspirated through the sampling needle and then expelled into the primary mixing reaction container for at least one reciprocating aspiration and expulsion cycle to obtain a diluted sample solution.
[0023] After the sampling needle completes one mixing cycle, it discharges the excess hemolytic agent and spits out purified water to clean the inner wall of the needle.
[0024] After the sampling needle completes one cleaning cycle, it sequentially draws in buffer solution, latex, and the diluted sample solution to form a liquid distribution of purified water, surplus buffer solution, buffer solution to be mixed, latex, and diluted sample solution in the internal liquid path. After aspiration, the diluted sample solution, latex, and buffer solution to be mixed are completely discharged from the sampling needle into the secondary mixing reaction container using the initial discharge volume for secondary mixing, forming a turbid liquid, while the surplus buffer solution is retained in the liquid path. After the initial discharge, a portion of the turbid liquid is drawn in through the sampling needle and then discharged into the secondary mixing reaction container for at least one cycle of aspiration and discharge to obtain the sample solution to be tested.
[0025] The technical solution of the present invention has the following beneficial technical effects:
[0026] 1. The present invention provides a method for mixing sample solution using a sampling needle of an in vitro diagnostic instrument. By retaining excess reagent between purified water and the mixed solution in the liquid path, the method aims to minimize the impact of purified water replacing part of the reagent or the mixed solution entering the mixed solution and affecting the concentration of specific proteins in the mixed solution. This results in more accurate protein concentration in the sample solution, improved mixing quality, reduced coefficient of variation of multiple parallel measurement results, and improved repeatability of the test results.
[0027] In conventional sampling methods, during the aspiration, initial drainage, and mixing processes, the purified water in the syringe's internal fluid path comes into direct contact with the reagent or mixture, leading to mixing at the interface. Some purified water replaces the reagent or sample solution / mixture, resulting in a decrease in protein concentration in the sample solution. This causes variations in the results of multiple parallel measurements due to the influence of purified water, resulting in a large coefficient of variation. This invention utilizes a pre-set amount of reagent surplus retained in the syringe's internal fluid path to minimize mixing of purified water with the reagent or mixture to be mixed, reducing the impact of purified water on the concentration of specific proteins in the mixture. Furthermore, even if surplus reagent replaces the mixture in the fluid path and enters the mixing reaction vessel, the impact on the concentration of specific proteins in the mixture is minimal because the mixture already contains reagent. In summary, this invention's method of retaining surplus reagent in the fluid path reduces the influence of purified water on the mixture, improves the stability of specific protein concentrations in the mixture, reduces the coefficient of variation in multiple parallel measurements, and improves the repeatability of the test results.
[0028] 2. In the method of the present invention, gas is inhaled before the excess reagent is inhaled to form an isolation gas column between the purified water and the excess reagent. The isolation gas column can decouple / isolate the purified water and the mixture, completely preventing the purified water from replacing part of the reagent or the mixture and entering the sample solution / mixture. At the same time, the excess reagent can prevent the isolation gas column from entering the mixture, thus avoiding the generation of bubbles during the aspiration and mixing process.
[0029] 3. During the aspiration and mixing process, in order to prevent the formation of air bubbles in the mixture due to the entrainment phenomenon, the sampling needle is placed in the mixing reaction container before aspiration and mixing, and the needle tip is positioned below the liquid surface of the mixture formed in the mixing reaction container after the sampling needle has absorbed part of the turbid liquid during aspiration and mixing.
[0030] 4. The method of the present invention, based on extensive test data, corrects the aspiration and expulsion coefficients of the sampling needle for a specific protein analyzer during the first and second mixing stages, i.e., the coefficient relationship between the volume of liquid aspirated in each reciprocating cycle and the corresponding initial expulsion volume. For the first mixing stage, the volume of liquid aspirated in each reciprocating cycle is 0.5 to 0.6 times, preferably 0.56 times, the initial expulsion volume of the first mixing stage; for the second mixing stage, the volume of liquid aspirated in each reciprocating cycle is 0.56 to 0.62 times, preferably 0.59 times, the initial expulsion volume of the second mixing stage. This method involves drawing in and expelling half or slightly more than half of the initial turbid liquid during the aspiration and expulsion process to flush out the remaining mixture in the reaction vessel. This repeated aspiration and expulsion process produces a good mixing effect, avoiding both insufficient aspiration volume (which results in poor mixing) and excessive aspiration volume (which causes the needle tip to protrude above the liquid surface and draw in air, reducing the stability of the mixture). Furthermore, the shorter descent and retraction time of the sampling needle allows for reduced testing time while maintaining a more economical reagent usage, meeting the machine's requirement of 60 CRP samples per hour.
[0031] 5. This method adjusts the amount of liquid expelled during the last reciprocating motion of the aspiration-expulsion mixing process to be less than the amount of liquid aspirated, so as to avoid the excess reagent remaining in the liquid path of the needle from mixing with the mixture and affecting the detection results. Attached Figure Description
[0032] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0033] Figure 1 This is the liquid distribution in the sampling needle of a specific protein analyzer in Example 1 before the initial drainage of the sample solution after one mixing of the sample solution;
[0034] Figure 2 This is the liquid distribution in the sampling needle of a specific protein analyzer before the initial drainage, after the sample solution has been mixed twice in Example 1.
[0035] Figure 3 This is a diagram showing the relative position of the sampling needle tip in the reaction cup during the mixing process of the sample solution via aspiration and expulsion.
[0036] Figure 4 This is a diagram showing the relative position of the sampling needle tip in the reaction cup during the secondary mixing process of the sample solution;
[0037] Figure 5 This is Example 2, showing the liquid distribution in a specific protein analyzer sampling needle before the initial drainage of the sample solution after one mixing of the sample solution.
[0038] Figure 6 This is Example 2, showing the liquid distribution in a specific protein analyzer sampling needle before the initial drainage of the sample solution after secondary mixing of the sample solution.
[0039] Figure labels: 1-Purified water, 2-Isolation air column, 31-Excess hemolysin, 32-Hemolysin to be mixed, 31'-Excess buffer solution, 32'-Buffer solution to be mixed, 4-Original blood sample, 5-Leak-proof air column, 6-Latex, 7-Diluted blood sample, 8-Sampling needle, 91-Primary mixing reaction cup, 92-Secondary mixing reaction cup, 10-Primary mixing liquid surface, 11-Secondary mixing liquid surface. Detailed Implementation
[0040] Example 1
[0041] A method for mixing sample solution using a sampling needle of a specific protein analyzer includes the following steps:
[0042] (1) The sampling needle of the specific protein analyzer sequentially draws in a hemolysing agent, the original blood sample, and 5 μL of air to form a liquid distribution in the needle's internal liquid path consisting of purified water 1, surplus hemolysing agent 31, hemolysing agent to be mixed 32, the original blood sample 4, and a leak-proof air column 5. Figure 1 As shown, the volume of the inhalation solution of the surplus hemolytic agent 31 is 5 μL;
[0043] (2) The sampling needle 8 moves into the primary mixing reaction cup 91 and is located at the longitudinal center of the primary mixing reaction cup 91. The position of the sampling needle tip is preset below the primary mixing liquid surface 10 formed after the sampling needle draws in 0.56 times the initial amount of turbid liquid from the primary mixing. Figure 3 As shown, the piston action of the plunger pump then pushes the sampling needle to completely discharge the leak-proof liquid column, the original blood sample and the hemolysin to be mixed from the needle tip into the first mixing reaction cup 91 to form a turbid liquid, while the excess hemolysin is retained in the liquid path.
[0044] (3) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the first mixing reaction cup 91 three times to mix it once. The amount of liquid aspirated each time is 0.56 times the amount expelled in the first mixing (i.e., the aspirate and expulsion coefficient of the first mixing is 0.56). The amount of liquid expelled in the reciprocating process is equal to the amount of liquid aspirated, thus obtaining the diluted sample solution.
[0045] (4) After the sampling needle completes one mixing, it moves to the top of the cleaning tank to discharge the excess hemolysing agent and spray purified water to clean the inner wall of the needle.
[0046] (5) The sampling needle of the specific protein analyzer sequentially draws in buffer solution, latex, and diluted sample solution obtained after one mixing, along with 5 μL of air, to sequentially form a liquid distribution in the needle's internal liquid path consisting of purified water 1, surplus buffer 31', buffer solution to be mixed 32', latex 6, diluted blood sample 7, and a leak-proof air column 5, as follows: Figure 2 As shown, the aspirate volume of surplus buffer 31' is 5 μL;
[0047] (6) The sampling needle 8 moves into the secondary mixing reaction cup 92 and is located at the longitudinal center of the secondary mixing reaction cup 92. The position of the sampling needle tip is preset below the position of the secondary mixing liquid surface 11 formed after the sampling needle 8 draws in 0.59 times the amount of turbid liquid initially discharged during secondary mixing. Figure 4 As shown, the piston action of the plunger pump then pushes the sampling needle to completely expel the leak-proof liquid column, diluted sample, latex and buffer solution to be mixed from the needle tip at the initial discharge volume of the secondary mixing, forming a turbid liquid in the secondary mixing reaction cup 92, and retaining the excess buffer solution in the liquid path;
[0048] (7) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the secondary mixing reaction cup 92 three times to perform secondary mixing. The amount of liquid aspirated each time is 0.59 times the amount expelled in the first secondary mixing (i.e., the secondary mixing aspirate and expulsion coefficient is 0.59). The amount of liquid expelled during the reciprocating process is equal to the amount of liquid aspirated, thus obtaining the sample liquid to be tested.
[0049] (8) After the sampling needle completes the second mixing, it moves to the top of the washing pool, drains the excess buffer solution, and spits out purified water to wash the inner wall of the needle.
[0050] Example 2
[0051] A method for mixing sample solution using a sampling needle of a specific protein analyzer includes the following steps:
[0052] (1) After the sampling needle of the specific protein analyzer first draws in air, it sequentially draws in the hemolysing agent and the original blood sample, and then draws in air a second time. This creates a liquid distribution in the needle's internal liquid path consisting of purified water 1, an isolation air column 2, surplus hemolysing agent 31, hemolysing agent to be mixed 32, the original blood sample 4, and a leak-proof liquid air column 5, as follows: Figure 5 As shown, the first inhalation of air volume was 15 μL, the second inhalation of air volume was 5 μL, and the inhalation volume of the surplus hemolysin 31 was 5 μL.
[0053] (2) The sampling needle 8 moves into the first mixing reaction cup 91 and is located at the longitudinal center of the first mixing reaction cup 91. The position of the sampling needle tip is preset below the position of the first mixing liquid surface 10 formed after the sampling needle draws in 0.56 times the amount of turbid liquid in the first mixing. Then, the piston action of the plunger pump pushes the sampling needle to completely discharge the leak-proof liquid column 5, the original blood sample 4 and the hemolysin 32 to be mixed from the needle tip with the amount of the first mixing. Turbid liquid is formed in the first mixing reaction cup, and the excess hemolysin 31 is retained in the liquid path.
[0054] (3) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the mixing reaction cup three times to mix it once. The amount of liquid aspirated each time is 0.56 times the amount expelled in the first mixing. The amount of liquid expelled in the reciprocating process is equal to the amount of liquid aspirated, thus obtaining the diluted sample solution.
[0055] (4) After the sampling needle completes one mixing, it moves to the top of the cleaning pool, discharges the excess hemolysin and isolation air column, and spits out purified water to clean the inner wall of the needle.
[0056] (5) After the sampling needle of the specific protein analyzer first draws in air, it sequentially draws in buffer solution, latex, and the diluted sample solution obtained after one mixing, and then draws in air a second time. This creates a liquid distribution in the needle's internal liquid path consisting of purified water 1, isolation air column 2, surplus buffer 31', buffer solution to be mixed 32', latex 6, diluted blood sample 7, and leak-proof air column 5, as follows: Figure 6 As shown, the first intake of air was 15 μL, the second intake of air was 5 μL, and the intake of the surplus buffer 31' was 5 μL.
[0057] (6) The sampling needle 8 moves into the secondary mixing reaction cup 92 and is located at the longitudinal center of the secondary mixing reaction cup 92. The position of the sampling needle tip is preset below the position of the secondary mixing liquid surface 11 formed after the sampling needle draws in 0.59 times the amount of turbid liquid from the initial secondary mixing. Then, the piston action of the plunger pump pushes the sampling needle to completely discharge the leak-proof liquid column 5, diluted blood sample 7, latex 6 and buffer solution 32' from the needle tip to perform the initial secondary mixing and discharge. Turbid liquid is formed in the secondary mixing reaction cup, and the excess buffer solution 31' is retained in the liquid path.
[0058] (7) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the secondary mixing reaction cup three times to perform secondary mixing. The amount of liquid aspirated each time is 0.59 times the amount expelled in the first secondary mixing. The amount of liquid expelled in the reciprocating process is equal to the amount of liquid aspirated, thus obtaining the sample liquid to be tested.
[0059] (8) After the sampling needle completes the second mixing, it moves to the top of the cleaning pool, discharges the excess buffer and isolation air column, and spits out purified water to clean the inner wall of the needle.
[0060] Example 3
[0061] This embodiment provides a method for mixing sample liquid with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the aspiration-exposure coefficient for one mixing is 0.50, and the position of the sampling needle tip during one mixing process is preset below the position 10 of the first mixing liquid surface formed after the sampling needle aspirates 0.50 times the amount of turbid liquid expelled in the first mixing.
[0062] Example 4
[0063] This embodiment provides a method for mixing sample liquid with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the aspiration-exposure coefficient for one mixing is 0.53, and the position of the sampling needle tip during one mixing process is preset below the position 10 of the first mixing liquid surface formed after the sampling needle aspirates 0.53 times the amount of turbid liquid expelled in the first mixing.
[0064] Example 5
[0065] This embodiment provides a method for mixing sample solution with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the aspiration-exposure coefficient for one mixing is 0.58, and the position of the sampling needle tip during one mixing process is preset below the position 10 of the first mixing liquid surface formed after the sampling needle aspirates 0.58 times the amount of turbid liquid expelled in the first mixing.
[0066] Example 6
[0067] This embodiment provides a method for mixing sample liquid with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the aspiration-exposure coefficient for one mixing is 0.60, and the position of the sampling needle tip during one mixing process is preset below the position 10 of the first mixing liquid surface formed after the sampling needle aspirates 0.60 times the amount of turbid liquid expelled in the first mixing.
[0068] Example 7
[0069] This embodiment provides a method for mixing sample liquid with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the secondary mixing aspiration coefficient is 0.56, and the position of the sampling needle tip during the secondary mixing process is preset below the secondary mixing liquid surface 11 formed after the sampling needle aspirates 0.56 times the amount of turbid liquid expelled during the first secondary mixing.
[0070] Example 8
[0071] This embodiment provides a method for mixing sample liquid with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the secondary mixing aspiration coefficient is 0.62, and the position of the sampling needle tip during the secondary mixing process is preset below the secondary mixing liquid surface 11 formed after the sampling needle aspirates 0.62 times the amount of turbid liquid expelled during the first secondary mixing.
[0072] Example 9
[0073] This embodiment provides a method for mixing sample solution using a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the aspiration coefficient for the first mixing and the aspiration coefficient for the second mixing are both 0.71. In the first mixing process, the position of the sampling needle tip is preset below position 10, which is the first mixing liquid surface formed after the sampling needle draws in 0.71 times the amount of turbid liquid initially expelled in the first mixing. In the second mixing process, the position of the sampling needle tip is preset below position 11, which is the second mixing liquid surface formed after the sampling needle draws in 0.71 times the amount of turbid liquid initially expelled in the second mixing.
[0074] Example 10
[0075] This embodiment provides a method for mixing sample solution with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the volume of the residual hemolysin 31 aspirated during the first mixing process is 10 μL, and the volume of the residual buffer 31' aspirated during the second mixing process is 10 μL.
[0076] Example 11
[0077] This embodiment provides a method for mixing sample solution with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the volume of the residual hemolysin 31 aspirated during the first mixing process is 15 μL, and the volume of the residual buffer 31' aspirated during the second mixing process is 15 μL.
[0078] Example 12
[0079] This embodiment provides a method for mixing sample solution with a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the volume of liquid expelled in the last reciprocating motion during the first and second mixing processes is less than 10 μL of liquid aspirated.
[0080] Example 13
[0081] This embodiment provides a method for mixing sample solution using a sampling needle of a specific protein analyzer. The difference from Embodiment 1 is that the aspiration coefficient for the first mixing and the aspiration coefficient for the second mixing are both 0.40. In the first mixing process, the position of the sampling needle tip is preset below position 10, which is formed after the sampling needle draws in 0.40 times the amount of turbid liquid initially expelled in the first mixing. In the second mixing process, the position of the sampling needle tip is preset below position 11, which is formed after the sampling needle draws in 0.40 times the amount of turbid liquid initially expelled in the second mixing.
[0082] Comparative Example 1
[0083] This comparative example describes a method for mixing sample solution using a specific protein analyzer sampling needle, comprising the following steps:
[0084] (1) The sampling needle of the specific protein analyzer sequentially draws in hemolysing agent, raw blood sample and 5ul of air to form a liquid distribution of purified water, hemolysing agent, raw blood sample and leak-proof liquid air column in the liquid path inside the needle.
[0085] (2) The sampling needle moves into the longitudinal center of the first mixing reaction cup, and the position of the sampling needle tip is preset below the position of the first mixing liquid surface formed after the sampling needle draws in 0.40 times the initial discharge volume of turbid liquid. Then, the piston action of the plunger pump pushes the sampling needle to completely discharge the leak-proof liquid column, the original blood sample and the hemolysin from the needle tip with the initial discharge volume of the first mixing to form turbid liquid in the first mixing reaction cup.
[0086] (3) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the mixing reaction cup three times to mix it once. The amount of liquid aspirated each time is 0.40 times the amount expelled in the first mixing. The amount of liquid expelled in each reciprocating motion is equal to the amount of liquid aspirated, thus obtaining a diluted sample solution.
[0087] (4) After the sampling needle completes one mixing, it moves to the top of the cleaning pool and spits out purified water to clean the inner wall of the needle.
[0088] (5) The sampling needle of the specific protein analyzer sequentially draws in buffer, latex, diluted sample solution obtained after one mixing, and 5ul of air to sequentially form a liquid distribution of purified water, buffer, latex, diluted blood sample and leak-proof air column in the liquid path inside the needle.
[0089] (6) The sampling needle moves into the secondary mixing reaction cup and is located at the longitudinal center of the secondary mixing reaction cup. The position of the sampling needle tip is preset below the position of the secondary mixing liquid surface formed after the sampling needle draws in 0.40 times the amount of turbid liquid expelled in the initial secondary mixing. Then, the piston action of the plunger pump pushes the sampling needle to completely expel the leak-proof liquid column, diluted sample, latex and buffer from the needle tip with the amount of the initial secondary mixing, forming turbid liquid in the secondary mixing reaction cup.
[0090] (7) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the secondary mixing reaction cup three times to perform secondary mixing. The amount of liquid aspirated each time is 0.40 times the amount expelled in the first secondary mixing. The amount of liquid expelled in each reciprocating motion is equal to the amount of liquid aspirated, thus obtaining the sample liquid to be tested.
[0091] (8) After the sampling needle completes the second mixing, it moves to the top of the cleaning pool and spits out purified water to clean the inner wall of the needle.
[0092] Comparative Example 2
[0093] The method for mixing sample solution with a specific protein analyzer sampling needle in this comparative example differs from Example 9 in that excess hemolysin was not aspirated in step (1) and excess buffer was not aspirated in step (5).
[0094] Comparative Example 3
[0095] The method for mixing sample solution with a specific protein analyzer sampling needle in this comparative example differs from Example 1 in that excess hemolysin is not aspirated in step (1) and excess buffer is not aspirated in step (5).
[0096] Comparative Example 4
[0097] A method for mixing sample solution using a sampling needle of a specific protein analyzer includes the following steps:
[0098] (1) After the sampling needle of the specific protein analyzer first inhales air, it inhales hemolysing agent and raw blood sample in sequence, and then inhales air a second time to form a liquid distribution of purified water, isolation air column, hemolysing agent, raw blood sample and leak-proof liquid air column in sequence in the liquid path inside the needle. The amount of air inhaled in the first time is 15ul and the amount of air inhaled in the second time is 5ul.
[0099] (2) The sampling needle moves into the longitudinal center of the first mixing reaction cup, and the position of the sampling needle tip is preset below the position of the first mixing liquid surface formed after the sampling needle draws in 0.56 times the amount of turbid liquid in the first mixing. Then, the piston action of the plunger pump pushes the sampling needle to completely discharge the leak-proof liquid column, the original blood sample and the hemolysin from the needle tip with the amount of the first mixing, and the turbid liquid is formed in the first mixing reaction cup.
[0100] (3) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the mixing reaction cup three times to mix it once. The amount of liquid aspirated each time is 0.56 times the amount expelled in the first mixing. The amount of liquid expelled in each reciprocating motion is equal to the amount of liquid aspirated, thus obtaining a diluted sample solution.
[0101] (4) After the sampling needle completes one mixing, it moves to the top of the cleaning pool, emits an isolation air column, and uses purified water to clean the inner wall of the needle.
[0102] (5) After the sampling needle of the specific protein analyzer first inhales air, it inhales buffer, latex and diluted sample solution in sequence, and then inhales air a second time to form a liquid distribution of purified water, isolation air column, buffer, latex, diluted sample solution and leak-proof liquid air column in sequence in the liquid path inside the needle. The amount of air inhaled in the first time is 15ul and the amount of air inhaled in the second time is 5ul.
[0103] (6) The sampling needle moves into the secondary mixing reaction cup and is located at the longitudinal center of the secondary mixing reaction cup. The position of the sampling needle tip is preset below the position of the secondary mixing liquid surface formed after the sampling needle draws in 0.59 times the amount of turbid liquid expelled in the initial secondary mixing. Then, the piston action of the plunger pump pushes the sampling needle to completely expel the leak-proof liquid column, diluted sample solution, latex and buffer solution from the needle tip in the initial expulsion volume, forming turbid liquid in the secondary mixing reaction cup.
[0104] (7) By reciprocating the piston of the plunger pump, the sampling needle is driven to aspirate and expel the turbid liquid in the secondary mixing reaction cup three times to perform secondary mixing. The amount of liquid aspirated each time is 0.59 times the amount expelled in the first secondary mixing. The amount of liquid expelled in each reciprocating motion is equal to the amount of liquid aspirated, thus obtaining the sample liquid to be tested.
[0105] (8) After the sampling needle completes the second mixing, it moves to the top of the cleaning pool, discharges the isolation air column, and spits out purified water to clean the inner wall of the needle.
[0106] Test case
[0107] The sampling needle aspirated the sample solutions obtained in the examples and comparative examples, respectively, and injected them into the test container of a specific protein analyzer for C-reactive protein (CRP) content detection. The same sample was tested 10 times in parallel, and the standard deviation of the ten measurements was calculated. The average of ten measurements The results are shown in Tables 1 and 2.
[0108] Table 1. Results of ten parallel measurements of C-reactive protein content in Examples 1-13 and Comparative Examples 1 and 4
[0109]
[0110]
[0111] As shown in Table 1, compared to Comparative Example 1, Examples 1-13, by inhaling excess reagent before sampling and retaining it in the needle's internal fluid path after the initial drainage, resulted in more accurate measurements of protein content in blood across multiple parallel tests, a lower coefficient of variation, and improved repeatability. Comparative Example 4, with its isolation air column exposed after the initial drainage, was prone to introducing air bubbles into the mixture during the aspiration and regurgitation process, leading to reduced repeatability, a low coefficient of variation, and poor repeatability.
[0112] Table 2. Comparison of the method of the present invention and the method of the comparative example under the same intake / output coefficient.
[0113] Standard deviation of ten measurements coefficient of variation First-time mixing and aspiration coefficient Secondary mixing and absorption coefficient Example 1 0.68 2.84％ 0.56 0.59 Comparative Example 3 0.98 4.19％ 0.56 0.59 Example 9 0.96 3.75％ 0.71 0.71 Comparative Example 2 1.12 5.33％ 0.71 0.71 Example 13 1.17 3.82％ 0.40 0.40 Comparative Example 1 1.42 5.98％ 0.40 0.40
[0114] As can be seen from Table 2, compared with Comparative Example 3, Comparative Example 2, and Comparative Example 13, under the same aspiration and expulsion coefficient settings, the methods of Examples 1, 9, and 13 of this application reduce the influence of purified water on the mixture by setting surplus reagent in the liquid path, and the coefficient of variation of their test results are all lower than those of the corresponding comparative examples that do not aspirate surplus reagent.
[0115] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for mixing sample solution using a sampling needle in an in vitro diagnostic instrument, characterized in that, This includes sequential steps of aspiration, initial drainage, and aspiration-dispensing mixing. The liquid aspiration step is as follows: reagents and samples are sequentially aspirated through the sampling needle of the in vitro diagnostic instrument to sequentially form a liquid distribution of purified water, surplus reagent, reagent to be mixed and sample in the liquid path inside the needle; The initial drainage step is as follows: after the aspiration is completed, the sample and the reagent to be mixed in the sampling needle are completely discharged into the mixing reaction container to form a turbid liquid with the initial discharge volume, and the excess reagent is retained in the liquid path; The aspiration and mixing step is as follows: after the initial drainage is completed, a portion of the turbid liquid is aspirated through the sampling needle and then discharged into the mixing reaction container for at least one reciprocating aspiration and mixing step to obtain the sample liquid. The reagent consists of buffer solution and latex, the surplus reagent is surplus buffer solution, the sample is a diluted sample, the sample solution is the sample solution to be tested, and the volume of liquid aspirated and expelled by the sampling needle during aspiration and mixing is 0.56 to 0.62 times the initial expulsion volume.
2. The method according to claim 1, characterized in that, The liquid aspiration step also includes a first step of aspirating air before the sampling needle aspirates the reagent. After the liquid aspiration is completed, a liquid distribution of purified water, isolation air column, surplus reagent, reagent to be mixed and sample is formed in sequence in the liquid path inside the needle.
3. The method according to claim 1, characterized in that, During the initial drainage step, the sampling needle is placed inside the mixing reaction container at the longitudinal center of the mixing reaction container, and the position of the sampling needle tip is preset below the liquid level of the mixture formed in the mixing reaction container after the sampling needle has absorbed part of the turbid liquid during the reciprocating suction and discharge.
4. The method according to claim 1, characterized in that, The in vitro diagnostic instrument is a specific protein analyzer.
5. The method according to claim 4, characterized in that, The reagent consists of buffer solution and latex, the surplus reagent is surplus buffer solution, the sample is a diluted sample, the sample solution is the sample solution to be tested, and the volume of liquid aspirated and expelled by the sampling needle during aspiration and mixing is 0.59 times the volume expelled initially.
6. The method according to claim 1, characterized in that, In the inhalation and mixing step, the amount of liquid expelled in the last repetition is less than the amount of liquid inhaled each time. And / or, the volume of the surplus reagent in the aspirate solution is 5-15 μL.
7. The method according to claim 2, characterized in that, The intake volume of the gas forming the isolation column is 10-20 μL; And / or, the liquid aspiration step further includes a second air aspiration step after the sampling needle aspirates the sample, to form a leak-proof air column below the sample.
8. The application of the method according to any one of claims 1-7 in in vitro diagnostic instrument detection and analysis.
9. The application according to claim 8, characterized in that, The application of the method in detecting the content of a specific protein in a sample using a specific protein analyzer includes the following steps: The hemolysing agent and the original sample are sequentially aspirated through a sampling needle of a specific protein analyzer to form a liquid distribution of purified water, surplus hemolysing agent, hemolysing agent to be mixed, and the original sample in sequence within the needle's internal liquid path. After aspiration, the original sample and hemolysing agent to be mixed are completely expelled from the sampling needle into a primary mixing reaction container to form a turbid liquid, while the surplus hemolysing agent remains in the liquid path. After the initial expulsion, a portion of the turbid liquid is aspirated through the sampling needle and then expelled into the primary mixing reaction container for at least one reciprocating aspiration and expulsion cycle to obtain a diluted sample solution. After the sampling needle completes one mixing cycle, it discharges the excess hemolytic agent and spits out purified water to clean the inner wall of the needle. After the sampling needle completes one cleaning cycle, it sequentially draws in buffer solution, latex, and the diluted sample solution to form a liquid distribution of purified water, surplus buffer solution, buffer solution to be mixed, latex, and diluted sample solution in the internal liquid path. After aspiration, the diluted sample solution, latex, and buffer solution to be mixed are completely discharged from the sampling needle into the secondary mixing reaction container using the initial discharge volume for secondary mixing, forming a turbid liquid, while the surplus buffer solution is retained in the liquid path. After the initial discharge, a portion of the turbid liquid is drawn in through the sampling needle and then discharged into the secondary mixing reaction container for at least one cycle of aspiration and discharge to obtain the sample solution to be tested.