A gold nanoparticle-based immunochromatographic assay for simultaneous detection of multiplex sildenafil adulterants in health food by only one antibody.

In the last few years, sildenafil and its analogues have emerged as an illegal ingredient in health food and products, causing illness and death. To address this problem, herein, a gold nanoparticle-based immunochromatographic assay for simultaneous detection sildenafil and its analogues was developed by using just one monoclonal antibody. This method can realize qualitative and quantitative analysis of sildenafil and its analogues with a detection range (IC20-IC80) of 0.12-28.05 ng mL-1, the IC50 was 0.31-8.45 ng mL-1 and the cut-off value was 5.0-80.0 ng mL-1. Meanwhile, this method could also accomplish semi-quantitative analysis of vardenafil with a cut-off value of 0.625 ng mL-1. The detection can be finished in 6 min and showed no cross-reactivity with avanafil and tadalafil. The recoveries of spiked samples ranged from 70.5 to 118.9% with a coefficient variation less than 15%, which confirmed the assay was sensitive, accurate and adapted to the rapid determination of sildenafil and its analogues.