INTENDED USE

Hepatitis B Surface Antigen (HBsAg) Rapid Tesk Dipstick (Whole Blood/serum/plasma) is a rapid chromatographic immunoassay for the qualitative detection of Hepatitis B Surface Antigen in whole blood , serum and plasma.

SUMMARY

Following an HBV infection, HBsAb is generally the last antibodies to appear. Its presence indicates clinical recovery of the patient and subsequent immunity to HBV infection. It is also associated with immunity produced post immunisation. HBsAb detects the presence of HBsAb in human serum and is useful to (a) monitor success of therapy from an acute HBV infection (b) determine past exposure to Hepatitis B surface antigen and (c) testing for immunity to Hepatitis B.

PRINCIPLE

HBsAb is based on the principle of agglutination of antibodies/ antisera with respective antigen in a immuno-chromatography format along with use of nano gold particles as agglutination. The conjugate pad is impregnated with two components – HBsAg conjugated to colloidal gold and rabbit globulin conjugated to colloidal gold. As the test specimen flows through the membrane assembly of the device, the HBsAg- colloidal gold conjugate complexes with the HBsAb in the test specimen and travels on the membrane due to capillary action along with the rabbit-globulin colloidal gold conjugate. This complex moves further on the membrane to the test region (T) where it is immobilized by HBsAg antigen coated on the membrane, leading to formation of a pink/purple coloured band. The absence of this band in the test region (T) indicates a negative result.

The rabbit globulin-colloidal gold conjugate and unbound complex if any move further on the membrane and are subsequently immobilized by the Agglutinating sera for rabbit globulin coated on the membrane at the control region (C) forming a pink / purple coloured band. This control band acts as a procedural control and serves to validate the test results.