Green-synthesized two-dimensional nanocarriers with photothermal capability for portable dual-readout immunochromatographic assay of clenbuterol

Immunochromatographic test strips (ITSs) have gained great practicability in point-of-care testing (POCT). Developing novel labels of ITSs with an additional signal to carry out quantitative analysis favors the development of sensitive POCT. Herein, tannic acid (TA) assisted stripping WS 2 nanosheets (TA-WS 2 NSs) based on colorimetric/photothermal ITS (TWITS) for clenbuterol (CLE) monitoring. After WS 2 NSs loaded TA, it retained excellent photothermal performance and an intact surface structure for monoclonal antibody (mAb) labeling, at the same time, the stability of WS 2 NSs and the activity of mAb were improved effectively. Satisfactory, the visual limit of detection (vLOD) of the photothermal signal was 0.3 ng/mL, which was enhanced 7-fold at least compared with traditional gold-based nanoparticles ITS (GNPs ITS). Importantly, this work can offer a new referenced method for other small molecule pollutants.