Insulin radioimmunoassay kit instructions

【Drug Name】

Common name: Iodine [125I] insulin radioimmunoassay kit

English name: Iodine [125I] Insulin Radioimmunoassay Kit

Chinese Pinyin: Dian [125I] Yidaosu Fangshemianyifenxi Yaohe

Insulin radioimmunoassay kit [ingredients]

Insulin radioimmunoassay kit [Properties] The liquid components (except the immunoseparating agent) should be clear, without precipitation or flocs; the lyophilized components should be loose, and after reconstitution, there should be no precipitates or flocs.

[Half-life of radionuclide] The nuclide used in this product is iodine [125I], and its physical half-life (T½) is 60 days.

Insulin radioimmunoassay kit [clinical significance]

Insulin (Ins., Referred to as Ins.) Is a protein hormone that is synthesized by the islet β cells and secreted after processing. It consists of 51 amino acids. The two peptide chains are α and β, which are linked together by two disulfide bonds. With a molecular weight of 5734D. The insulin structure of different species of animals is slightly different from that of human insulin. The structure of porcine insulin is the most similar to that of human, except that the last amino acid on the β chain is different. Therefore, the two have obvious cross-reactions in immunoassays.

Insulin is a hormone that promotes synthesis, and its main role is to promote glucose oxidation and glycogen production, inhibit gluconeogenesis, and maintain blood sugar constant. In the absence of insulin, the blood glucose concentration rises, which can exceed the renal glucose threshold, and insulin-dependent diabetes occurs.

This kit is used for the determination of insulin content in serum or plasma. It is mainly used for the study of the secretory function of pancreatic β cells and diabetes, to determine the type of diabetes; for the diagnosis of insulinoma, to explore the mechanism of coronary heart disease, to study certain drugs The influence of sugar metabolism and endocrine disorders diseases have certain significance and value.

Insulin radioimmunoassay kit [Determination principle]

Using the principle of homogeneous competition inhibition, the equilibrium competition method is used for direct determination of serum or plasma. Ins. In the standard or sample and the labeled antigen will compete with a limited amount of specific antibodies for a competitive immune response. When the concentration of Ins. In the sample is high, less labeled antigen is bound to the antibody, and vice versa. The antigen-antibody complex is separated with an immunoisolating agent, and the radioactivity in the conjugate is measured. The amount of labeled antigen is in a functional relationship with Ins. In the sample. Therefore, the Ins. Concentration in the sample can be calculated through mathematical processing.

Insulin radioimmunoassay kit [applicable instrument] is suitable for all types of ν-radioimmunoassay analyzers.

Insulin radioimmunoassay kit [sample requirements]

Take venous blood to separate serum and wait for test; plasma needs to add anticoagulant, mix well, and then separate plasma and wait for test; if not to measure immediately, seal the sample and store at 2 ～ 8 ℃ or -20 ℃ According to the test, the storage at 2 ～ 8 ℃ should not exceed 1 week, and the storage at -20 ℃ should not exceed 2 months. Frozen samples should be protected from repeated freezing and thawing during storage. Before measuring the frozen sample, let the sample melt in room temperature or normal temperature water and shake it well.

Insulin radioimmunoassay kit [Usage and Dosage]

1 Reagent preparation, usage and storage

(1) Ins. Standard product: freeze-dried product, add 1ml of buffer to each bottle of standard product to dissolve. Shake well after dissolving for 15 minutes. After dissolution, the standard concentration values ​​were 5,15,45,135,405μIU / ml. After standard reconstitution, it can be stored for 42 days at 2 ～ 8 ℃, and the lyophilized product is stable within -20 ℃.

(2) 125I-Ins .: lyophilized product, dissolve with 10ml buffer solution for 100 tubes, and dissolve with 5ml buffer solution for 50 tubes. Store at 2 ～ 8 ℃, stable within the validity period. If more than 100 tubes are added at one time, use them after mixing the two bottles. The radioactivity of 100 markers is not greater than 111 KBq (3μCi).

(3) Dolphin anti-Ins. Antibody: lyophilized product, dissolved in buffer solution, add 6ml per bottle of antibody (if not filled in 100T plus 10ml, 50T plus 5ml buffer solution). After the antibody is dissolved, it can be stable for 42 days when stored at 2-8 ° C, and the lyophilized product is stable during the storage period of -20 ° C.

(4) Donkey Anti-Dolphin Immune Separation Agent: liquid, it must be shaken well before loading! Store at 2 ～ 8 ℃, stable within the validity period. Stable within 42 days after opening.

(5) Ins. Buffer solution: liquid, stored at 2 ～ 8 ℃, stable within the validity period. Stable within 42 days after opening.

(6) Ins. Quality Control Serum: freeze-dried product, add 0.5ml of distilled water to each bottle of Quality Control Serum before use to dissolve. After reconstitution, it can be stored for 42 days at 2 ～ 8 ℃, and the lyophilized product is stable within -20 ℃. For the validity period and value-added, please refer to the applicable instructions of the quality control serum.

2 Measurement steps

Take a number of round bottom polystyrene test tubes, use a marker or special pencil to number NSB, S0 ~ S5 and the sample tube to be tested, etc., then use the micro sampler to add samples according to the table below. Before loading, all reagents (especially the separating agent!) Including the sample to be tested should be shaken, and it is best to equilibrate to room temperature.

Sample loading program unit: μl

3 Data processing

(1) Online processing: the result is automatically processed by the computer. Note that due to different principles of radioimmunoassay and immunoradiotherapy, the processing software is also different. Users must use suitable processing software for data processing. It is recommended that users use logit-log or four-parameter data processing mode.

(2) Hand drawing or calculator processing:

1). Percentage binding rate calculation: S0 tube count is B0, each standard tube or sample tube count is B, and non-specific tube count is NSB, then the percentage binding rate calculation formula is: B / B0 = (B－NSB ) / (B0－NSB) × 100%

2). Logit calculation: The calculation formula of the logit value of each standard point or sample tube is: logit = ln (B / B0) / (1-B / B0)

3). Hand work diagram: take the log value of the standard concentration as the abscissa, the corresponding logit value as the ordinate on the ordinary coordinate paper or the standard concentration as the abscissa, and the corresponding B / B0 as the ordinate in the logit-log Draw a standard curve (a straight line when idealized) on paper. According to the B / B0 of the sample to be tested, the concentration value of the sample can be found from the coordinate paper. Note: If you use ordinary graph paper, the detected value should take the logarithm to be the final concentration value.

4). Calculator processing: using a calculator with linear fitting function, the sample concentration value can be calculated more conveniently, please refer to the instruction manual of the calculator for the specific operation method.

Examples of standard curves (for reference only, not for actual calculations). Concentration unit: μIU / ml

Insulin radioimmunoassay kit [reference normal value]

Fasting serum insulin reference normal value: 14.0 ± 8.7μIU / ml, range 5 ～ 25μIU / ml.

The peak value of serum CP after a meal is about 5 times that of a fasting. The peak generally appears 30 to 60 minutes after a meal (it has a certain relationship with the type of food eaten), and it is close to the fasting value after 3 hours.

Unit conversion: Ins. Standard antigen of this batch, 1mg = 25IU

Due to different regions and instruments used, there will be some differences in the measured normal values, so the normal values ​​provided in this manual are for reference only. It is best for each laboratory to establish a range of normal values ​​that meets the requirements of this laboratory.

Insulin radioimmunoassay kit [product performance indicators]

1. Measuring range: 5 ～ 405μIU / ml.

2. Sensitivity: 2μIU / ml.

3. Precision: intra-batch coefficient of variation (CV) <10%; inter-batch coefficient of variation (CV) <15%.

4. Term of use: See product packaging.

Insulin radioimmunoassay kit [taboo] This product is for in vitro diagnosis only!

Insulin radioimmunoassay kit 【Notes】

1. After receiving the kit, store it at 2 ～ 8 ℃ as soon as possible.

2. Please read this manual carefully before use.

3. The components of the same kind of kits in different kits or in different months cannot be mixed.

4. When aspirating the supernatant, be careful not to lose the sediment, otherwise it will significantly affect the measurement results.

5. When the Ins. Concentration in the sample is higher than 405μIU / ml, the sample can be diluted 5-10 times with buffer solution and then retested. The measured concentration multiplied by the dilution factor is the sample concentration.

6. Please use the kit within the validity period.

7. Clinical specimens should be considered potentially infectious, please follow the laboratory procedures for infectious diseases.

8. The use of this kit should pay attention to radiological protection, and radioactive waste must be handled in accordance with the regulations of radiological protection.