An ultrasensitive fluorescent paper sensor for fast screening of berberine.

Berberine (BBR) is a highly effective animal feed additive, but it also has adverse side effects on animals and causes potential food safety issues. Here, based on the preparation of a BBR monoclonal antibody, we developed a rapid, simple and sensitive lateral flow immunoassay (LFIA) using gold nanoparticle (GNP)- and fluorescent microsphere (FM)-labelled BBR antibodies for quantitative detection of BBR in feed samples. Under a hand-held optical scanner, the limits of detection of the GNP-LFIA and FM-LFIA were found to be 4.40 μg kg−1 and 2.00 μg kg−1, respectively, in feed samples. The spiked feed samples had acceptable recovery rates using the LFIAs, and the results were further confirmed by liquid chromatography/mass spectrometry. The actual feed sample test results by GNP-LFIA and FM-LFIA also showed good consistency. These two LFIAs provide a good option for fast screening of BBR on-site in feed samples. [ABSTRACT FROM AUTHOR]