RAPID DETECTION KIT FOR ANTIBODY-ANTIGEN RECOGNIZATION FOR HUMAN IMMUNODEFICIENCY VIRUS

Nurul Shahirah Rokman, Noor Aimie-Salleh, Norhana Jusoh, Siti Aisyah Mualif*

Abstract

Human immunodeficiency virus type 1 (HIV-1) capsid p24 protein is one of the most important
components in viral pathogenesis. It is highly secreted in the blood serum during early stage of HIV-1 that act as a
biomarker for early diagnosis. Enzyme immunoassays (EIAs) is a conventional test to detect human
immunodeficiency virus (HIV) by incorporating p24 antigen detection with current HIV antibody detection.
However, this method requires many steps and time-consuming. Therefore, it is necessary to develop a new
diagnostic approach that is easier and faster than this conventional test. In this study, a rapid detection kit using
colloidal gold was developed to detect the presence of p24 antigen in blood serum. The detection kit strip that has
been developed composed of a sample pad, an absorbent pad, conjugate pad, and a nitrocellulose membrane
containing control and test line. The nanocolloidal gold, with an average particle diameter of 30 nanometres (nm)
was labelled with anti-HIV-1 p24 antibody as the detection reagent. An antibody colloidal gold probe was applied
on the conjugate pad. Anti-HIV-1 p24 antibody was immobilized to test line as the capture reagent and HIV-1 p24
antigen on the control line at the nitrocellulose membrane in order to prepare this detection kit. The
commercialized p24 antigen was added onto the sample pad and reacts with anti-HIV-1 p24 antibody conjugated
with colloidal gold particle. The mixture then migrates to the nitrocellulose membrane and react with anti-HIV-1
p24 in the detection zone which resulting in red marks within this detection zone with an intensity proportional to
the concentration of the p24 antigen in the sample. The result can be observed within less than 10 minutes.