THE RAPID 1-2-3® HEMA CASSETTE HEPATITIS B TEST
The RAPID 1-2-3® HEMA CASSETTE HEPATITIS B TEST (the TEST) is an in vitro, rapid, qualitative two site sandwich immunoassay used for the detection of Hepatitis B Surface Antigen (HBsAg) in human whole blood, serum, and plasma.
Blood containing the Hepatitis B Virus (HBV) is potentially infectious. Hepatitis B Surface Antigen (HBsAg), earlier known as Australia Antigen, is among the first serological markers that circulate in the blood of infected persons even two to three weeks prior to the appearance of clinical symptoms. The levels of HBsAg are especially elevated during the symptomatic phase and decline thereafter.
Detection of HBV using HBsAg as the marker to screen blood donors is essential to reduce the risk of transmission of Hepatitis B by blood transfusion. HBsAg detection is also useful for screening high risk groups for HBV and for differential diagnosis of Hepatitis infections.
The RAPID 1-2-3® HEMA CASSETTE HEPATITIS B (HBsAg) TEST detects the presence of HBsAg in whole blood specimens or serum/plasma, qualitatively, at concentrations as low as 0.5 ng/ml.
PRINCIPLES OF THE TEST
The RAPID 1-2-3® HEMA CASSETTE HEPATITIS B (HBsAg) TEST utilizes the principle of Immunochromatography, a unique two site immunoassay on a membrane. As the test sample flows through the membrane assembly within the test device, the colored anti-HBsAg-colloidal gold conjugate complexes with HBsAg in the sample. This complex moves further on the membrane to the test region where it is immobilized by the anti-HBsAg coated on the membrane leading to formation of a pink-purple colored band which confirms a positive test result. Absence of this colored band in the test region indicates a negative test result. The remaining conjugate and unbound complex if any, along with rabbit IgG gold conjugate move further on the membrane and are subsequently immobilized by the anti-mouse antibodies coated on the membrane at the control region, forming a pink-purple colored band. This control band serves to validate the test results.