Computer-assisted hapten design enables aptamer and hybrid aptamer-antibody rapid assays for detection of citrinin in red yeast rice.

Citrinin (CTN), a nephrotoxic and hepatotoxic mycotoxin frequently found in red yeast rice, requires rapid and reliable detection. Here, six CTN haptens were rationally designed using computational chemistry, and two optimal structures were selected for generating CTN-specific aptamers via systematic evolution of ligands by exponential enrichment (SELEX). Based on these aptamers (Apts), four analytical platforms were developed, including enzyme-linked aptamer sorbent assay (ELASA), aptamer-based lateral flow strip (Apt-LFS), hybrid enzyme-linked aptamer-antibody assay (ELAAA), and hybrid lateral flow strip (Hybrid-LFS). The limits of detection were 1.9, 500, 10, and 250 ng/mL, respectively. In spiked red yeast rice samples, ELASA and ELAAA showed average recoveries of 102% and 104%. Analysis of 15 commercial samples showed excellent consistency with HPLC, while Apt-LFS and Hybrid-LFS identified four positive samples according to Taiwan Food and Drug Administration (TFDA) limits. This study provides a sensitive and practical strategy for CTN monitoring in complex food matrices.