Qi Wang1, Mei Ling Hou2, Li Peng Liu2, Jing Ma3, Xiao Guang Zhang3, Zhi Xiang Zhou1, Yu Xi Cao3. 1. Beijing University of Technology, College of Life Science and Bioengineering, Beijing 100124, China. 2. Beijing Runbio Biotechnology Development Co., Ltd, Beijing 100106, China. 3. National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
Abstract
OBJECTIVE: To develop a rapid, highly sensitive quantitative method for detecting P24 antigen based on near-infrared fluorescent microsphere immunochromatography. METHODS: First, we prepared a lateral flow assay test strip, and labeled the detection antibody using a fluorescent microsphere. Second, we optimized the antibody labeling conditions. Third, we optimized the detection conditions. Fourth, we created a working curve. Fifth, we conducted a methodological assessment of the established fluorescent microsphere immunochromatography method. Sixty-six clinical samples were tested, and we compared the established fluorescent microsphere immunochromatography with the quantitative ELISA method. RESULTS: According to the working curve, the detection limit of the method is 3.4 pg/mL, and the detection range is 3.4 pg/mL to 10 ng/mL. The average intra-assay recovery was 99.6%, and the Coefficient of Variation (CV) was 5.4%-8.6%; the average inter-assay recovery was 97.3%, and the CV was 8.5%-11%. The detection rate of fluorescent microsphere immunochromatography was higher than ELISA method, and had a good correlation with ELISA. CONCLUSION: The P24 antigen quantitative detection method based on near-infrared fluorescent microsphere immunochromatography has the advantages of rapid detection, high sensitivity, and wide detection range; thus, it is suitable for early clinical diagnosis and continuous monitoring of AIDS.
OBJECTIVE: To develop a rapid, highly sensitive quantitative method for detecting P24 antigen based on near-infrared fluorescent microsphere immunochromatography. METHODS: First, we prepared a lateral flow assay test strip, and labeled the detection antibody using a fluorescent microsphere. Second, we optimized the antibody labeling conditions. Third, we optimized the detection conditions. Fourth, we created a working curve. Fifth, we conducted a methodological assessment of the established fluorescent microsphere immunochromatography method. Sixty-six clinical samples were tested, and we compared the established fluorescent microsphere immunochromatography with the quantitative ELISA method. RESULTS: According to the working curve, the detection limit of the method is 3.4 pg/mL, and the detection range is 3.4 pg/mL to 10 ng/mL. The average intra-assay recovery was 99.6%, and the Coefficient of Variation (CV) was 5.4%-8.6%; the average inter-assay recovery was 97.3%, and the CV was 8.5%-11%. The detection rate of fluorescent microsphere immunochromatography was higher than ELISA method, and had a good correlation with ELISA. CONCLUSION: The P24 antigen quantitative detection method based on near-infrared fluorescent microsphere immunochromatography has the advantages of rapid detection, high sensitivity, and wide detection range; thus, it is suitable for early clinical diagnosis and continuous monitoring of AIDS.