RAPID DETECTION OF ASIATICOSIDE BY IMMUNOCHROMATOGRAPHIC ASSAY

Abstract

s. PHYTOPHARM 2012 M 62 Obzory po kliniceskoj farmacologii i lekarstvennoj terapii [Reviews of clinical pharmacology and drug therapy] ТОМ 10/2012/2 RAPID DETECTION OF ASIATICOSIDE BY IMMUNOCHROMATOGRAPHIC ASSAY © Sritularak B., Juengwatanatrakul T. , Putalun W ., Tanaka H. , Morimoto S. 4 Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand Faculty of Pharmaceutical Sciences, Ubon Ratchathani University, Ubon Ratchathani, 34190, Thailand Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen, 40002, Thailand Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan Asiaticoside (AS), [6[[3,4-dihydroxy-6(hydroxymethyl)-5(3,4,5-trihydroxy-6-methyloxan-2-yl)oxyoxan-2-yl]oxymethyl]-3,4,5-trihydroxyoxan-2-yl] 10,11-dihydroxy-9(hydroxyme-thyl)-1,2,6a,6b,9,12a-hexamethyl-2,3,4,5,6,6a,7,8,8a,10,11, 12,13,14b-tetradecahydro-1h-picene-4a-carboxylate, has been identified as the most active compound in Centella asiatica (l.) urb. in order to screen large numbers of samples for the presence of AS, a rapid and simple technique is required for application to small quantities of test samples. immunoassays using monoclonal antibodies could be useful for the determination of small quantities of AS in plant extracts (1). in this study, an immunochromatographic strip test has been developed for the detection of AS in plant samples using monoclonal antibody against AS (2). The qualitative assay was based on a competitive immunoassay in which the detector reagent consisted of colloidal gold particles coated with the respective AS antibodies.The capture reagent was an AS-human serum albumin (hSA) conjugate immobilized onto a test strip membrane. The sample containing AS and the detection reagent were incubated with the immobilized capture reagent. The AS in the sample competed in binding to the limited amount of antibodies in the detection reagent with the immobilized AShSA conjugates and, hence, positive samples showed no color in the capture spot zone. The detection limit for the strip test was 12.5 μg/ml. The immunochromatographic strip test is useful as a rapid and simple screening method for the determination of small quantities of AS in plant extracts, body fluids and foods.