General formula and process for improving coupling efficiency of CK-MB latex reagent

Abstract

The invention discloses a general formula and process for improving the coupling efficiency of a CK-MB latex reagent, and the general formula is composed of a suspension, a dispersion liquid and a stabilizing liquid. The formula suspension liquid comprises the following components: a first buffer solution and an activating agent; the general formula dispersion liquid comprises the following components: a second buffer solution and a surfactant; the general formula stabilizing solution comprises the following components: a third buffer solution, a sealing agent, a stabilizing agent and a preservative. And a proper amount of surfactant is added into the dispersion liquid, so that the dispersity of the reaction system is greatly improved, the specific binding efficiency of the antibody and the latex microspheres is improved, and coagulation is avoided. The CK-MB latex reagent provided by the invention is better in quality stability and high in coupling rate, coagulation of the latex reagent is effectively avoided, and the dispersity is good, so that the detection sensitivity is high, and the accuracy is good; the problems of low coupling efficiency, easy coagulation, low sensitivity and poor repeatability in the prior art are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of biochemical detection, and in particular relates to a general formula and process for improving the coupling efficiency of a CK-MB latex reagent. Background Art

[0002] Creatine kinase isoenzyme CK-MB is one of the important indicators for early diagnosis of acute myocardial infarction.

[0003] At present, the mainstream methods for CK-MB determination include immunosuppression, immunofluorescence chromatography, chemiluminescence, and latex immunoturbidimetry. The immunosuppression method completely ignores the existence of CK-BB and is easily interfered by other kinases in the blood, and the results are prone to false positives; although the immunofluorescence chromatography method does not require large equipment, it has low sensitivity; the chemiluminescence method has strong specificity and high sensitivity, but the development cost is high and the cycle is long. The tracer residue in the antibody labeling process may increase the background signal interference, and the integration requirements of the fully automatic analysis equipment are higher. The latex immunoturbidimetry method effectively overcomes the difficulties of the above methods, the detection process is faster, and it is suitable for various brands of fully automatic biochemical analyzers, and can be promoted on a large scale.

[0004] At present, most manufacturers in the market need to perform high-speed separation and ultrasonic dispersion of the reaction system during the preparation of latex reagents, which makes the operation complicated and places strict operating requirements on production personnel, affecting production efficiency and making it impossible to uniformize the quality. At the same time, the prepared latex reagents usually have the disadvantages of low coupling efficiency, easy coagulation, low sensitivity and poor repeatability. Summary of the invention

[0005] The invention discloses a general formula and process for improving the coupling efficiency of CK-MB latex reagent, so as to solve the problems existing in the prior art, such as complex raw material screening conditions, low antibody-latex microsphere coupling efficiency, easy coagulation, low sensitivity, poor repeatability, etc.

[0006] In a first aspect of the present invention, a general formula and process for improving the coupling efficiency of CK-MB latex reagent are provided, wherein the general formula comprises the following components: a suspension, a dispersion and a stabilizing solution; wherein:

[0007] The suspension comprises the following components: 0.04-0.16 g / L of an activator; the remainder being a first buffer;

[0008] The dispersion comprises the following components: 0.01-0.05% of a surfactant; the remainder is a second buffer solution;

[0009] The stabilizing solution comprises the following components: 0.01-0.04 g / L of a sealing agent; 50-100 g / L of a stabilizing agent; 0.5-2.0 g / L of a preservative; and the remainder is a third buffer solution.

[0010] Optionally, the activator includes EDC and NHS, and the addition ratio of EDC and NHS is 1:1.

[0011] Optionally, the first buffer is selected from MES or HEPES buffer.

[0012] Optionally, the surfactant is selected from one of sodium dodecylbenzene sulfonate, Tween 20, Triton X-100, Brij30 or Brij35.

[0013] Optionally, the second buffer is selected from one of phosphate, MOPS or HEPES buffer.

[0014] Optionally, the blocking agent is selected from one of BSA, ethanolamine, DB1130, CE210 or CE510.

[0015] Optionally, the stabilizer is selected from one of sucrose, mannitol or trehalose.

[0016] Optionally, the preservative is selected from one of sodium azide, Cassonon or PC300.

[0017] Optionally, the third buffer is selected from one of Tris, glycine, HEPES, MOPS or TAPS buffer.

[0018] The second aspect of the present invention provides a process for improving the coupling efficiency of CK-MB latex reagent, comprising:

[0019] Mixing the activator and the first buffer to obtain a suspension;

[0020] Adding latex microspheres into the suspension to perform suspension activation to obtain an initial solution;

[0021] Adding the dispersion liquid and the antibody to the initial liquid to perform a coupling reaction to obtain an intermediate liquid;

[0022] The stabilizing solution is added to the intermediate solution to obtain the final latex reagent.

[0023] The present invention adopts the above technical solution and has the following advantages:

[0024] (1) The present invention provides a general formula for improving the dispersibility and stability of CK-MB antibody-latex microsphere conjugates, which is composed of three parts: a suspension, a dispersion, and a stabilizing solution. The general formula can be used as an independent and general reagent, suitable for the preparation of most latex reagents, reducing the process of exploring coating conditions one by one, making the preparation of latex reagents simpler and more convenient.

[0025] (2) In the general formula provided by the present invention, an appropriate amount of surfactant is added to the dispersion, which greatly improves the dispersibility of the reaction system, thereby improving the specific binding efficiency of the antibody and the latex microspheres without coagulation.

[0026] (3) The present invention provides a process for improving the dispersibility and stability of antibody-latex microsphere conjugates. In the process of preparing CK-MB latex reagent, a one-step non-centrifugation process is adopted. The entire preparation process does not require centrifugation, which greatly simplifies the operation steps, reduces production costs, reduces the operating requirements for production personnel, improves quality stability, and has a high coupling rate. It effectively avoids the precipitation of the latex reagent and has good dispersibility, so the detection sensitivity is high and the accuracy is good. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the present application, the latex microspheres are carboxylated polystyrene latex microspheres, the particle size of the latex microspheres is 300-350 nm, and the mass concentration is 10-20 mg / L.

[0029] The antibody is CK-MB monoclonal antibody with a mass concentration of 40-60 mg / L.

[0030] Example 1

[0031] The general formula provided in Example 1 of the present application mainly includes a suspension, a dispersion and a stabilizing solution, wherein:

[0032] Each 1L suspension includes the following components: 0.02g EDC (carbodiimide), 0.02g NHS (N-hydroxysuccinimide), and the balance is MES buffer (2-morpholineethanesulfonic acid, concentration of 20mmol / L, pH 5.2);

[0033] Each 1L dispersion includes the following components: 100uL Tween 20, the balance is HEPES buffer (4-hydroxyethylpiperazineethanesulfonic acid, concentration of 20mmol / L, pH 7.0);

[0034] Each 1L of stabilizing solution includes the following components: 0.01g CE510, 50g sucrose, 0.5g PC300 (isothiazolinone), and the balance is TAPS buffer (tris(hydroxymethyl)methylaminopropanesulfonic acid, concentration is 20mmol / L, pH is 7.4);

[0035] Each 100 mL of CK-MB latex reagent provided in Example 1 of the present application includes the following components: 20 mL of suspension, 1 mg of carboxylated polystyrene latex particles with a particle size of 300 nm, 20 mL of dispersion, 4 mg of CK-MB monoclonal antibody, and 60 mL of stabilizing solution.

[0036] In this embodiment, the preparation process of 100mL CK-MB latex reagent specifically includes the following steps:

[0037] (1) Take 20 mL of MES buffer with a concentration of 20 mmol / L and a pH of 5.2, add 0.0004 g EDC (carbodiimide) and 0.0004 g NHS (N-hydroxysuccinimide) to make a fresh suspension, and place it in a reaction cup;

[0038] (2) taking 1.0 mg of carboxylated polystyrene latex microspheres with a particle size of 300 nm, slowly adding it dropwise to the above suspension, stirring and activating for 10 minutes to obtain an initial solution;

[0039] (3) Add 20 mL of dispersion and 4 mg of CK-MB monoclonal antibody to the reaction cup and stir for 2 h;

[0040] (4) ultrasonication for 1-5 minutes (ultrasonication conditions: power 35 W, 4 ° C, ultrasonication 2 s, interval 2 s) to obtain a dispersed intermediate solution;

[0041] (5) Add 60 mL of stabilizing solution to the intermediate solution of step (4), stir and react for 12 h to obtain the final CK-MB latex solution.

[0042] Example 2

[0043] The general formula provided in Example 2 of the present application mainly includes a suspension, a dispersion, and a stabilizing solution, wherein:

[0044] Each 1L of suspension includes the following components: 0.04g EDC (carbodiimide), 0.04g NHS (N-hydroxysuccinimide), and the balance is MES buffer (2-morpholineethanesulfonic acid, concentration of 20mmol / L, pH 6.5);

[0045] Each 1L dispersion includes the following components: 200uL Triton X-100, the balance is MOPS buffer (3-(N-morpholino)propanesulfonic acid, concentration is 20mmol / L, pH is 7.5);

[0046] Each 1L of stabilizing solution includes the following components: 0.02g CE210, 100g sucrose, 1g PC300 (isothiazolinone), and the balance is MOPS buffer (3-(N-morpholino)propanesulfonic acid, concentration of 20mmol / L, pH 8.0);

[0047] Each 100 mL of CK-MB latex reagent provided in Example 2 of the present application includes the following components: 20 mL of suspension, 1.5 mg of carboxylated polystyrene latex particles with a particle size of 300 nm, 20 mL of dispersion, 4 mg of CK-MB monoclonal antibody, and 60 mL of stabilizing solution.

[0048] In this embodiment, the preparation process of 100mL CK-MB latex reagent specifically includes the following steps:

[0049] (1) Take 20 mL of MES buffer with a concentration of 20 mmol / L and a pH of 6.5, add 0.0008 g EDC (carbodiimide) and 0.0008 g NHS (N-hydroxysuccinimide) to make a fresh suspension, and place it in a reaction cup;

[0050] (2) taking 1.5 mg of carboxylated polystyrene latex microspheres with a particle size of 300 nm, slowly adding it dropwise to the above suspension, stirring and activating for 15 minutes to obtain an initial solution;

[0051] (3) Add 20 mL of dispersion and 4 mg of CK-MB monoclonal antibody to the reaction cup and stir for 2 h;

[0052] (4) ultrasonication for 1-5 minutes (ultrasonication conditions: power 35 W, 4 ° C, ultrasonication 2 s, interval 2 s) to obtain a dispersed intermediate solution;

[0053] (5) Add 60 mL of stabilizing solution to the intermediate solution of step (4), stir and react for 12 h to obtain the final CK-MB latex solution.

[0054] Example 3

[0055] The general formula provided in Example 3 of the present application mainly includes a suspension, a dispersion, and a stabilizing solution, wherein:

[0056] Each 1L suspension includes the following components: 0.05g EDC (carbodiimide), 0.05g NHS (N-hydroxysuccinimide), and the balance HEPES buffer (4-hydroxyethylpiperazineethanesulfonic acid, concentration of 20mmol / L, pH 6.5);

[0057] Each 1L dispersion includes the following components: 300uL sodium dodecylbenzene sulfonate, the balance is HEPES buffer (4-hydroxyethylpiperazineethanesulfonic acid, concentration is 20mmol / L, pH is 7.0);

[0058] Each 1L of stabilizing solution includes the following components: 0.02g DB1130, 50g trehalose, 1g sodium azide (isothiazolinone), and the balance is Tris buffer (tris(hydroxymethyl)aminomethane, concentration is 20mmol / L, pH is 7.5);

[0059] Each 100 mL of CK-MB latex reagent provided in Example 3 of the present application includes the following components: 20 mL of suspension, 2 mg of carboxylated polystyrene latex particles with a particle size of 300 nm, 20 mL of dispersion, 5 mg of CK-MB monoclonal antibody, and 60 mL of stabilizing solution.

[0060] In this embodiment, the preparation process of 100mL CK-MB latex reagent specifically includes the following steps:

[0061] (1) Take 20 mL of 20 mmol / L HEPES buffer with a pH of 7.0, add 0.001 g EDC (carbodiimide) and 0.001 g NHS (N-hydroxysuccinimide) to make a fresh suspension, and place it in a reaction cup;

[0062] (2) taking 1.5 mg of carboxylated polystyrene latex microspheres with a particle size of 300 nm, slowly adding it dropwise to the above suspension, stirring and activating for 20 minutes to obtain an initial solution;

[0063] (3) Add 20 mL of dispersion and 5 mg of CK-MB monoclonal antibody to the reaction cup and stir for 2.5 h;

[0064] (4) ultrasonication for 1-5 minutes (ultrasonication conditions: power 35 W, 4 ° C, ultrasonication 2 s, interval 2 s) to obtain a dispersed intermediate solution;

[0065] (5) Add 60 mL of stabilizing solution to the intermediate solution of step (4), stir and react for 12 h to obtain the final CK-MB latex solution.

[0066] Example 4

[0067] The general formula provided in Example 4 of the present application mainly includes a suspension, a dispersion, and a stabilizing solution, wherein:

[0068] Each 1L suspension includes the following components: 0.06g EDC (carbodiimide), 0.06g NHS (N-hydroxysuccinimide), and the balance is HEPES buffer (4-hydroxyethylpiperazineethanesulfonic acid, concentration of 20mmol / L, pH 7.0);

[0069] Each 1L dispersion includes the following components: 400uL Brij30, the balance is phosphate buffer (concentration of 20mmol / L, pH 7.5);

[0070] Each 1L of stabilizing solution includes the following components: 0.04g ethanolamine, 100g trehalose, 2g sodium azide, and the remainder is glycine buffer (concentration of 20mmol / L, pH 7.5);

[0071] Each 100 mL of CK-MB latex reagent provided in Example 4 of the present application includes the following components: 20 mL of suspension, 1 mg of carboxylated polystyrene latex microparticles with a particle size of 350 nm, 20 mL of dispersion, 5 mg of CK-MB monoclonal antibody, and 60 mL of stabilizing solution.

[0072] In this embodiment, the preparation process of 100mL CK-MB latex reagent specifically includes the following steps:

[0073] (1) Take 20 mL of 20 mmol / L HEPES buffer with a pH of 7.0, add 0.0012 g EDC (carbodiimide) and 0.0012 g NHS (N-hydroxysuccinimide) to make a fresh suspension, and place it in a reaction cup;

[0074] (2) taking 1.0 mg of carboxylated polystyrene latex microspheres with a particle size of 350 nm, slowly adding it dropwise to the above suspension, stirring and activating for 25 minutes to obtain an initial solution;

[0075] (3) Add 20 mL of dispersion and 5 mg of CK-MB monoclonal antibody to the reaction cup and stir for 3 h;

[0076] (4) ultrasonication for 1-5 minutes (ultrasonication conditions: power 35 W, 4 ° C, ultrasonication 2 s, interval 2 s) to obtain a dispersed intermediate solution;

[0077] (5) Add 60 mL of stabilizing solution to the intermediate solution of step (4), stir and react for 24 hours to obtain the final CK-MB latex solution.

[0078] Example 5

[0079] The general formula provided in Example 5 of the present application mainly includes a suspension, a dispersion, and a stabilizing solution, wherein:

[0080] Each 1L of suspension includes the following components: 0.08g EDC (carbodiimide), 0.08g NHS (N-hydroxysuccinimide), and the balance is MES buffer (2-morpholineethanesulfonic acid, concentration of 20mmol / L, pH 5.2);

[0081] Each 1L dispersion includes the following components: 500uL Brij35, the balance is HEPES buffer (concentration of 20mmol / L, pH 7.0);

[0082] Each 1L of stabilizing solution includes the following components: 0.04g BSA, 100g mannitol, 1.5g casperone, and the remainder is HEPES buffer (4-hydroxyethylpiperazineethanesulfonic acid, concentration is 20mmol / L, pH is 7.5);

[0083] Each 100 mL of CK-MB latex reagent provided in Example 1 of the present application includes the following components: 20 mL of suspension, 1.5 mg of carboxylated polystyrene latex particles with a particle size of 350 nm, 20 mL of dispersion, 6 mg of CK-MB monoclonal antibody, and 60 mL of stabilizing solution.

[0084] In this embodiment, the preparation of 100mL CK-MB latex reagent specifically includes the following steps:

[0085] (1) Take 20 mL of MES buffer with a concentration of 20 mmol / L and a pH of 5.2, add 0.0016 g EDC (carbodiimide) and 0.0016 g NHS (N-hydroxysuccinimide) to make a fresh suspension, and place it in a reaction cup;

[0086] (2) taking 1.5 mg of carboxylated polystyrene latex microspheres with a particle size of 350 nm, slowly adding it dropwise to the above suspension, stirring and activating for 30 minutes to obtain an initial solution;

[0087] (3) Add 20 mL of dispersion and 6 mg of CK-MB monoclonal antibody to the reaction cup and stir for 3 h;

[0088] (4) ultrasonication for 1-5 minutes (ultrasonication conditions: power 35 W, 4 ° C, ultrasonication 2 s, interval 2 s) to obtain a dispersed intermediate solution;

[0089] (5) Add 60 mL of stabilizing solution to the intermediate solution of step (4), stir and react for 24 hours to obtain the final CK-MB latex solution.

[0090] Example 6

[0091] The CK-MB latex reagent provided in Examples 1 to 5 of the present invention was matched with homemade R1, and analyzed using a Toshiba TBA-120FR fully automatic biochemical analyzer using a two-point endpoint method. Each 1L of reagent R1 includes the following components: 50mg blocking agent, 1g sodium azide, 20g Nacl, 10g polyethylene glycol 6000, 0.5mL Tween 20, and the remainder is Tris buffer (concentration of 20mmol / L, pH of 7.5). The preparation method of R1 adopts conventional methods in the art, which will not be described in detail here.

[0092] The measurement parameters are as follows:

[0093] Reaction wavelength: 660nm; Sample volume: S: 10μl, R1: 150μl R2: 50μl; Reaction direction: upward reaction; Reaction temperature: 37℃; Reading points: After reagent R1 and sample are mixed, incubate at 37℃ for 300s, add R2 and incubate at 37℃ for 30s, read the absorbance value A1, after incubating at 37℃ for 270s, read the absorbance A2, and calculate the absorbance change value (△A=A2-A1); Calibration method: multi-point nonlinear calibration.

[0094] The performance test of the prepared CK-MB latex reagent was as follows:

[0095] (1) Intra-batch precision CV ≤ 5%, (2) Inter-batch precision CV ≤ 5%.

[0096] 1. Repeatability and stability verification

[0097] The CK-MB latex reagent prepared in Examples 1, 2, 3, 4, and 5 was used to detect the CK-MB content in samples of different intervals (low value, medium and high value) according to the test parameters to verify the repeatability and stability of the CK-MB latex reagent process prepared in the examples of the present invention. The specific results are shown in Table 1.

[0098] Table 1 Results of low and medium-high value samples tested in Examples 1, 2, 3, 4, and 5

[0099]

[0100]

[0101] It can be seen from the data in Table 1 that the CK-MB latex reagent prepared in the embodiment of the present invention has good process repeatability and stability.

[0102] 2. Comparative test and verification with purchased reagents

[0103] The CK-MB latex reagents prepared in Examples 1, 2, 3, 4, and 5 were selected for comparison with the kits with relatively high recognition in the market to verify the accuracy of the CK-MB latex reagents prepared in the examples of the present invention. The specific results are shown in Tables 2, 3, and 4.

[0104] Table 2 Calibration results of CK-MB latex reagents prepared in Examples 1, 2, 3, 4, and 5 of the present invention and purchased reagents

[0105]

[0106] It can be seen from the data in Table 2 that the CK-MB latex reagent prepared by the process of the present invention has higher sensitivity.

[0107] Table 3 Random sample results of comparative tests of reagents prepared in Examples 1, 2, 3, 4, and 5 of the present invention and purchased reagents

[0108]

[0109]

[0110] From the data in Table 3, it can be seen that the CK-MB latex reagent prepared by the process of the present invention is consistent with the random serum sample value tested by the control reagent.

[0111] Table 4 Third-party quality control results of the comparison test of the reagents prepared in Examples 1, 2, 3, 4, and 5 of the present invention and the purchased reagents

[0112]

[0113]

[0114] From the data in Table 4, it can be seen that the CK-MB latex reagent prepared by the process of the present invention and the control reagent are both under control in the third-party quality control, and the CK-MB latex reagent prepared by the process of the present invention has better test accuracy.

[0115] 3. Performance evaluation of the CK-MB latex reagent prepared by the present invention

[0116] The performance of the CK-MB latex reagent prepared by the present invention is evaluated by conducting relevant performance tests on the CK-MB latex reagent prepared by the present invention.

[0117] (1) Appearance evaluation

[0118] Visually inspected under natural light, the CK-MB latex reagent prepared by the present invention is a milky white solution, which is uniform and particle-free, and does not undergo coagulation.

[0119] (2) Repeatability evaluation

[0120] The test was repeated 5 times with samples of concentrations of (15±3) ng / mL and (30±5) ng / mL, respectively. The mean (M) and standard deviation (SD) of the 5 measurement results were calculated. The repeatability evaluation results are shown in Table 5.

[0121] Table 5 Repeatability evaluation results

[0122] sample (15±3)ng / mL (30±5)ng / mL 1 16.24 32.50 2 16.19 33.20 3 16.18 33.10 4 16.28 32.50 5 16.22 33.60 Standard Deviation 0.04 0.48 average value 16.22 32.98 CV value 0.25％ 1.44％

[0123] From the results in Table 5, it can be seen that after the samples of two concentrations were tested by the CK-MB latex reagent of the present invention, the CVs were 0.25% and 1.44%, respectively, indicating that the CK-MB latex reagent prepared by the present invention has good intra-batch repeatability.

[0124] (3) Stability assessment

[0125] The CK-MB latex reagents prepared in Examples 1, 2, 3, 4, and 5 were tested for stability in cold storage (4° C.), heat treatment (37° C.), and bottle opening (4° C.). The test results are shown in Tables 6 and 7.

[0126] Table 6 Stability evaluation results

[0127]

[0128] Table 7 Stability evaluation results

[0129]

[0130]

[0131] From the data in Table 6 and Table 7, it can be seen that the latex reagent prepared by the present invention is heat treated for 10 days and opened for 45 days, and the relative deviation of the measured value is less than ±10% compared with the refrigerated reagent, which shows that the CK-MB latex reagent prepared by the present invention has good stability.

[0132] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A general formula for improving the coupling efficiency of CK-MB latex reagent, characterized in that: The general formula includes the following components: suspension, dispersion and stabilizing solution; wherein, The suspension comprises the following components: 0.04-0.16 g / L of an activator; the remainder being a first buffer; The dispersion comprises the following components: 0.01-0.05% of a surfactant; the remainder is a second buffer solution; The stabilizing solution comprises the following components: 0.01-0.04 g / L of a sealing agent; 50-100 g / L of a stabilizing agent; 0.5-2.0 g / L of a preservative; and the remainder is a third buffer solution.

2. The general formula according to claim 1, characterized in that The activator includes EDC and NHS, and the addition ratio of EDC and NHS is 1:

1.

3. The general formula according to claim 1, characterized in that The first buffer is selected from MES or HEPES buffer.

4. The general formula according to claim 1, characterized in that The surfactant is selected from one of sodium dodecylbenzene sulfonate, Tween 20, Triton X-100, Brij30 or Brij35.

5. The general formula according to claim 1, characterized in that The second buffer is selected from one of phosphate, MOPS or HEPES buffer.

6. The general formula according to claim 1, characterized in that The blocking agent is selected from one of BSA, ethanolamine, DB1130, CE210 or CE510.

7. The general formula according to claim 1, characterized in that The stabilizer is selected from one of sucrose, mannitol or trehalose.

8. The general formula according to claim 1, characterized in that The preservative is selected from one of sodium azide, Cassonon or PC300.

9. The general formula according to claim 1, characterized in that The third buffer is selected from one of Tris, glycine, HEPES, MOPS or TAPS buffer.

10. A process for improving the coupling efficiency of CK-MB latex reagent, characterized in that: include: Mixing the activator and the first buffer to obtain a suspension; Adding latex microspheres into the suspension to perform suspension activation to obtain an initial solution; Adding the dispersion liquid and the antibody to the initial liquid to perform a coupling reaction to obtain an intermediate liquid; The stabilizing solution is added to the intermediate solution to obtain the final latex reagent.

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