LAUSR

Abstract To construct a rapid read-out analytical platform for detecting histamine in foods, a self-visualization nanomaterial was prepared by stable doping of ninhydrin into TiO2 nanoparticles (ninhydrin@TiO2) using a sol-gel strategy, and it was printed onto the target zone for histamine on a high-performance thin layer chromatography (HPTLC) strip based on the Rf value. Under the optimum TLC conditions, histamine in the sample migrates to the target zone, and the colorimetric reaction occurs in situ. The resultant color spots can be either identified visually or semi-quantitatively by image analysis. Owing to the stable visualization performance, the constructed strip demonstrated good contrast, with a low background and easily recognizable colored spots. The linear range was 15.0–320.0 mg kg−1, and the limit of detection for histamine in fish was 5.0 mg kg−1. Other biogenic amines such as putrescine and cadaverine did not interfere with the analysis. Furthermore, analytical results for fish samples were verified by HPLC tests, demonstrating the robustness and reliability of the developed method. Therefore, the incorporation of a self-visualization nanomaterial in the HPTLC platform is a promising strategy for the rapid analysis of food contaminants in the future.