High-flux smartphone-integrated lateral flow assay based on chrysanthemum-like Au@polydopamine for sensitive detection of enrofloxacin in milk

Abstract

Lateral flow assays (LFAs) are widely used in screening analysis. However, the detection flux and sensitivity of LFAs are unsatisfactory because of the ‘one-to-one’ read mode and the ordinary performance conventional probe. In this work, a high-flux smartphone-integrated LFA (sLFA) based on chrysanthemum-like Au@polydopamine (AuNC@PDA) for the detection of enrofloxacin (ENR) in milk was established. The smartphone-integrated device was developed and applied in the LFA, giving rise to a reading maximum of 64 samples with only two photos in less than 2 min compared to a ‘one-to-one’ read mode of a conventional LFA in more than 14 min with a 36.4% deviation. For ENR detection, the limits of detection of sLFA based on AuNC@PDA (33.78 pg mL⁻¹) had 5.0-fold and 6.4-fold reduction compared with those based on AuNP (169.99 pg mL⁻¹, conventional probe) and vvAuNP (216.47 pg mL⁻¹, commercial probe), respectively. This study provides an effective technical means for screening ENR in large quantities of milk samples.