Hepatitis B Surface Antigen HBsAg In Vitro Diagnostic Reagents For Automatic Immunoassay Analyzer In Infectious Disease

CLIA Reagents of Inflammation (HBsAg)

【Expected usage】
This product is used to quantitatively detect the content of hepatitis B virus surface antigen (HBsAg) in human serum in vitro.

Hepatitis B virus infection is distributed worldwide. About 350 million people in the world are infected with HBV, and my country accounts for about 1/3. HBV infection can cause inflammation and fibrosis of the liver, and severe cases may develop into cirrhosis and liver cancer. More than 1 million people die each year from end-stage liver disease and primary hepatocellular carcinoma.

Hepatitis B surface antigen (HBsAg) is the coat protein of hepatitis B virus. It was discovered by Blumberg in the blood of Australian aborigines in 1963 and is called Australian antigen. Hepatitis B virus belongs to the family Hepadnaviridae and is the smallest DNA virus found so far. Its genome is a double-stranded incomplete circular DNA, consisting of about 3200 base pairs, with 4 open reading frames (ORFs), namely S, C , P, X, respectively encode four major viral proteins-polymerase (P), X protein, envelope (S) and core protein (C). It is not infectious by itself, but its appearance is often accompanied by the presence of hepatitis B virus, so it is a sign of hepatitis B virus infection and the first serum marker to appear after infection with hepatitis B virus.

Changes in HBsAg throughout the course of chronic hepatitis B, seroclearance of HBsAg is considered to be a sign of chronic hepatitis B cure, so people are increasingly using serum HBsAg levels to monitor the natural history of chronic hepatitis B and antiviral efficacy of treatment.

【Inspection Principle】
This kit adopts the principle of direct sandwich method, and uses the combination of magnetic particle separation technology and chemiluminescence immunoassay system to detect the content of hepatitis B virus surface antigen (HBsAg) in human serum.

The technical principle is: Fluorescein isothiocyanate (FITC)-labeled hepatitis B virus surface antibody binds to alkaline phosphatase (AP)-labeled hepatitis B virus surface antibody and HBsAg in samples, calibrators or quality controls A "sandwich" complex is formed. Then, the magnetic particles linked with the anti-FITC antibody are added, and the antigen-antibody immune complex is bound to the magnetic particles through the specific binding of the anti-FITC antibody and FITC.

Under the action of an external magnetic field, the complex formed by the immune reaction is separated from other unbound substances, and after washing the complex, an enzymatic chemiluminescence substrate is added. The substrate is catalytically cleaved under the action of the enzyme to form an unstable excited state intermediate.

When the excited state intermediate returns to the ground state, photons are emitted to form a luminescence reaction, and the luminescence intensity of the reaction can be detected by a chemiluminescence instrument. Within the detection range, the luminescence intensity is proportional to the content of HBsAg in the sample, and the concentration of HBsAg in the sample can be calculated by fitting the modified four-parameter Logistic equation.