GMP Certificate HBsAg Test Kit Elisa Sandwich Enzyme Immunoassay For Human

HBsAg Elisa Test to detect Hepatitis B surface antigen,96wells/kit, Elisa Sandwich method, for quantitative measurement

Intended Use

The HBsAg EIA Test Kit is a one step enzyme immunoassay for the qualitative detection of Hepatitis B Surface Antigen (HBsAg) in human serum or plasma. It is intended for screening and as an aid in the diagnosis of possible Hepatitis B infection.

Summary

HBsAg is one of the earliest markers that appear in the blood following infection with Hepatitis B virus (HBV).1 This infection of the liver is transmitted through sexual contact, blood borne exposure, transmission from mother to child during delivery, sharing of objects that pierce the skin, child-to-child and household contact. The four major HBsAg subtypes include adw, adr, ayw, and ayr, all sharing the common determinant ‘a’. The HBV infection causes a wide variety of liver damage such as acute self-limiting infection, fulminating hepatitis, chronic hepatitis with progression to cirrhosis and liver failure, and asymptomatic chronic carrier state. In HBV infected people, the virus persists for the rest of their lives and can be passed on to others. Therefore, Hepatitis B has become a global public health problem. Infection with HBV results in the appearance of a number of serological markers and one of the first of such markers is Hepatitis B Surface Antigen (HBsAg). HBsAg appears 1-10 weeks after exposure and before biochemical evidence of liver disease or jaundice.2,3 Three weeks after the onset of acute hepatitis almost half of the patients will still be positive for HBsAg. In the chronic carrier state, HBsAg persists for 6-12 months with no seroconversion to the corresponding antibodies. Therefore, screening for HBsAg is highly recommended for all donors, pregnant women and people in high-risk groups. The HBsAg EIA Test Kit is a third generation immunoassay for the qualitative detection of the presence of Hepatitis B Surface Antigen in serum or plasma specimen. The test utilizes monoclonal antibodies to selectively detect various subtypes of HBsAg in serum or plasma

Test Principle

The HBsAg EIA Test Kit is a solid phase qualitative enzyme immunoassay based on a sandwich principle for the detection of HBsAg in human serum or plasma. The microwell plate is coated with monoclonal antibodies specific to various subtypes of HBsAg. During testing, the specimen and the enzymeconjugated HBsAg antibodies are added to the antibody coated microwell plate and then incubated. If the specimen contains HBsAg, it will bind to the antibodies coated on the microwell plate and simultaneously bind to the conjugate to form immobilized antibody-HBsAg-conjugate complexes. If the specimen does not contain HBsAg, the complexes will not be formed. After initial incubation, the microwell plate is washed to remove unbound materials. Substrate A and substrate B are added and then incubated to produce a blue color, indicating the amount of HBsAg present in the specimen. Sulfuric acid solution is added to the microwell plate to stop the reaction which produces a color change from blue to yellow. The color intensity, which corresponds to the amount of HBsAg present in the specimen, is measured with a microplate reader at 450/630-700 nm or 450 nm.

Unopened test kits should be stored at 2-8°C. DO NOT FREEZE KIT COMPONNETS. The microtiter plate should be kept in a sealed bag to minimize exposure to damp air. Use up the reagents as soon as possible after the kit is unpacked.

Dilute the 20X wash buffer concentrate with deionized or distilled water 1:20. For example, 5 ml of wash buffer concentrate should be diluted to a total volume of 100 mL with deionized or distilled water

1.  A run is valid if:

1) The full complement of Blanks, Positive and Negative Controls must be included in each assay.

2) Negative Control values must have an absorbance and ≤0.10 after subtracting the Blank.

3) Positive Control value must have absorbance ≥1.00 after subtracting the Blank.

2.  Calculation of Cut off Value (COV)

Mean of the Negative Controls (NCx)* 2.1

If the OD value of the negative control is less than 0.05, it should be reported as 0.05. If it is more than 0.05, it should be reported as the actual OD value measured.

Positive OD reading: ≥Cut-off value

Negative OD reading: < Cut-off value

This assay was standardized against Reference Standards provided from the Reference Laboratory for Immunology Product under the Ministry of Health, China.

Clinical Specificity: The clinical specificity of this assay was determinate by a panel of samples obtained from 2500 healthy blood donors and 300 undiagnosed hospitalized patients. The repeatedly reactive samples and samples confirmed positive with the reference test were not included in the calculation of specificity.