Novel Dual-Color Immunochromatographic Assay Based on Chrysanthemum-like Au@polydopamine and Colloidal Gold for Simultaneous Sensitive Detection of Paclobutrazol and Carbofuran in Fruits and Vegetables

Abstract

To ensure food safety and prevent the toxic effects of paclobutrazol (PBZ) and carbofuran (CAR) on humans, a sensitive and rapid method for the detection of PBZ and CAR in fruits and vegetables is required. Herein, a highly sensitive PBZ monoclonal antibody (PBZ mAb) and CAR monoclonal antibody (CAR mAb) with half-inhibitory concentrations (IC50) at 0.77 and 0.82 ng mL−1 were prepared, respectively. We proposed a novel dual-color immunochromatographic assay (ICA) with two test lines (T1 and T2) and an independent control line (C) based on chrysanthemum-like Au@Polydopamine (AuNC@PDA) and colloidal gold (AuNPs) for the simultaneous and sensitive detection of PBZ and CAR with naked-eye detection limits of 10 and 5 μg kg−1, respectively. The limits of detection (LOD) for PBZ and CAR were 0.117 and 0.087 μg kg−1 in orange, 0.109 and 0.056 μg kg−1 in grape, and 0.131 and 0.094 μg kg−1 in cabbage mustard, respectively. The average recoveries of PBZ and CAR in orange, grape, and cabbage mustard were 97.86−102.83%, with coefficients of variation from 8.94 to 11.05. The detection results of this method for 30 samples (orange, grapes, and cabbage mustard) agreed well with those of liquid chromatography–tandem mass spectrometry. The novel dual-color ICA was sensitive, rapid, and accurate for the simultaneous detection of PBZ and CAR in real samples.

An AgPd NP-based lateral flow immunoassay for simultaneous detection of glycocholic acid and alpha-fetoprotein

“…There is a pressing need for the development of rapid, simple, and sensitive methods for detecting GCA and AFP. Lateral ow immunoassay (LFIA) has the advantages of operational simplicity, and fast and accurate detection ability with multiple targets, 21,22 and has been widely used in environmental detection, food safety detection, 23,24 clinical diagnosis, and other elds. [25][26][27] To improve the sensitivity and effectiveness of LFIA, researchers have explored novel nanoparticles as alternatives to colloidal gold.…”

“…28,29 AgPd NPs, distinguished by darker colors with more intricate structures compared to AuNPs, exhibit a stronger optical signal, thereby improving LFIA's detection sensitivity. 22,30 AgPd composition is widely used in other elds with good performance, but is rarely used as a label in LFIA. At the same time, considering the economic cost compared to Pt and Au, Pd, as a precious metal, is cheaper.…”

Au Nanoclusters Embedded in Polydopamine for Photothermal Radiotherapy on Non-Small-Cell Lung Cancer

“…Synthesis of AuNC/PDA−RGD. The AuNC/PDA was prepared through a one-pot seedless coassembly strategy as described by Zhang et al 49,50 First, 4 mg/mL dopamine hydrochloride (3.6 mL) was injected into Tris−HCl buffer (72 mL, pH 8.5, 10 mM) under vigorous stirring for 3 min. Subsequently, 0.1% (w/v) HAuCl 4 (5.4 mL) and 8 μL of tween-20 were added in turn to the above solution.…”