Main content area

A colloidal gold probe-based silver enhancement immunochromatographic assay for the rapid detection of abrin-a

Yang, Wei, Li, Xiao-bing, Liu, Guo-wen, Zhang, Bing-bing, Zhang, Yi, Kong, Tao, Tang, Jia-jia, Li, Dong-na, Wang, Zhe
Biosensors & bioelectronics 2011 v.26 no.8 pp. 3710-3713
agglutinins, biosensors, cross reaction, detection limit, gold, immunoaffinity chromatography, polyclonal antibodies, silver, soymilk, toxins
High-affinity anti-abrin-a monoclonal and polyclonal antibodies were used to develop a sandwich immunochromatographic assay and silver enhancement technology was used to further increase the sensitivity. Using a matrix of double distilled water or soybean milk with added abrin-a, the visual detection limit was found to be 10ngmL⁻¹. The detection limit was 0.1ngmL⁻¹ for abrin-a, an increase in sensitivity of 100-fold when the silver enhancement technology was employed. The assay was portable and very simple to perform and the detection was completed within 20min without complicated handling procedures. There was no significant cross-reactivity with several homologous toxins and associated agglutinin. The assay reagents could be stored for 12weeks at 4°C without significant loss of activity. These characteristics make the strip assay to be an ideal candidate for the development of a rapid toxin detection kit.