Development of two immunochromatographic test strips based on gold nanospheres and gold nanoflowers for the rapid and simultaneous detection of aflatoxin B1 and aristolochic acid a in dual-use medicinal and food ingredients

Rapid, low-cost, and easy to use methods are required to detect small-molecule toxins. In this study, gold nanospheres (AuNSs) and gold nanoflowers (AuNFs) were synthesized and used to develop two immunochro-matographic test strips (ICS) based on gold nanospheres (SICS) and gold nanoflowers (FICS) for the rapid simultaneous detection of aflatoxin B1 (AFB1) and aristolochic acid (AA-A) in dual-use medicinal and food in-gredients. For the detection of AFB1 and AA-A, FICS (0.1 ng/mL for both AFB1 and AA-A) had a sensitivity up to 5 times and 50 times higher, respectively, than that of SICS (0.5 ng/mL for AFB1 and 5 ng/mL for AA-A). Moreover, the results of SICS and FICS with high-performance liquid chromatography showed good consistency, and there were no false positives or negatives. Gold nanoflower-based ICSs have the potential to be used on-site for detection with higher sensitivity requirements.