Dual-color immunochromatographic test strip for simultaneous sensitive detection of malachite green and leucomalachite green residues in fish and shrimp meat samples.

A sensitive dual immunochromatographic test strip (dual-ICTS) was developed to detect malachite green (MG) and its metabolite, leucomalachite green (LMG), using two types of gold nanoparticles: round-shaped (red) and star-shaped (blue). The detection limits were determined to be 0.221 μg L−1 for MG and 0.214 μg L−1 for LMG, respectively. The dual-ICTS provided a cut-off value of 1.8 μg L−1 for MG and LMG detection. The dual-ICTS successfully detected MG and LMG in food samples, with recovery rates ranging from 86 % to 116 %. The dual-ICTS was evaluated by correlation analysis between the proposed assay and the well-established enzyme-linked immunosorbent assay in the MG and LMG detection. This is the first report on the development of the ICTS that can detect both MG and LMG at the same time within only 5 min, making it a sensitive and rapid tool for on-site detection. [Display omitted] • Two colored gold nanoparticles were applied as dual - color labels in ICTS. • A novel dual-ICTS was fabricated for simultaneous detection of MG and LMG. • The dual-ICTS provided a cut-off value of 1.8 μg L−1 for MG and LMG detection. • ICTS is a rapid, for on-site simultaneous detection for MG and LMG within 5 min. [ABSTRACT FROM AUTHOR]