Dual-mode immunochromatography based on Ti3C2Tx functionalized CdTe quantum dots for chloramphenicol detection in animal-derived foods

In this study, Ti(3)C(2)Tx was coupled with CdTe quantum dots via plyethylenimine (PEI) mediation to form composite nanomaterials with dual colorimetric and fluorescent properties, which had strong pH, high ion strength, and organic solvent resistance. Then, this novel Ti(3)C(2)Tx@CdTe was firstly applied to develop a dual-mode immunochromatographic assay (ICA) for chloramphenicol (CAP) detection in animal-derived foods. The limits of detection of the colorimetric and fluorescent modes for CAP in milk/chicken/fish were 0.01 and 0.005 mu g/kg, the limits of quantification were 0.025 and 0.016 mu g/kg, the recovery rates were between 85.7% and 129.0% and 84.0%-119.2%, with the corresponding variations ranged from 6.5% to 14.8% and 6.4%-14.9%, respectively. The sensitivity of fluorescence mode was up to 100-fold higher than that of the reported ICA for CAP detection. The results of the confirmatory experiment on 30 samples showed good consistency with that of our established method (R-2>0.93). The above results indicated that Ti(3)C(2)Tx@CdTe had superior detection performance and can provide a dual-mode signal calibration, high stability and sensitivity selection for immunoassay detection platforms.