Iridium (IV) oxide-mediated microorganism nanozyme amplified immunochromatographic assay for dual-signal sensitive detection of salbutamol

Abstract

Salbutamol (SAL) residues in edible animal tissues have various adverse effects on human health after digestion. Herein, we constructed an innovative functionalized microorganism nanozyme-mediated immunochromatographic assay for sensitive and accurate dual-colorimetric detection of SAL by introducing the Yeast@IrO 2 as bifunctional signal tag. The Yeast@IrO 2 was synthesized by self-assembling iridium (IV) oxide nanoparticles (IrO 2 NPs) on the surface of inactivated yeast cells, which showed high monodispersity, uniform shapes, preeminent biocompatibility and rapid antibodies labeling capacity. After reaction for 15 min, through further employing [3,3′,5,5’ Tetramethylbenzidine (TMB) and hydrogen peroxide (H 2 O 2 )] as substrate to trigger the color reaction, the developed biosensor performed with outstanding performance, including limit of detection (0.012 ng/mL), linearity (R 2 > 0.99) and selectivity. Concurrently, the visual limit of detection (0.2 μg/kg) and satisfactory recoveries (85.6%–103.9%) were obtained by monitoring SAL in pig liver and beef samples. Briefly, this work provided a universal platform for sensitive, precise and rapid detection of toxic and hazardous substances in food safety fields. • A microorganism nanozyme-mediated ICA was developed to detect salbutamol. • The Yeast@IrO 2 was designed by self-assembling IrO 2 NPs on inactivated yeast cells. • The Yeast@IrO 2 generated colorimetric- and catalytic-based dual signals. • The sensor showed lower detection limit (0.012 ng/mL) and broader detection range. • The sensor could be applied to the detection of SAL in beef and pig liver samples.