Fabrication of Ferrum‐Doped TiO ₂ Nanocomposite for SERS Detection of Crystal Violet in Shrimp

ABSTRACT The residues of crystal violet (CV) in shrimp were easily absorbed by biological tissues and caused serious damage to human health. In this study, doped TiO 2 SERS substrates were fabricated with three doping metals including Fe, Cu, and Co by sol‐hydrothermal method. The SERS intensities reached the optimum at a Fe 3+ doping ratio of 5% with probe molecules of 4‐MBA and CV. The 5% Fe‐TiO 2 SERS substrates for monitoring CV residues obtained the best performance with LOD of 0.016 ppm and 0.03 ppm for standard solutions and shrimp protein extract solutions, respectively. The results indicated suitable doping metals could effectively modulate the energy bands of the semiconductor and improve the charge transfer between the substrate and analyte for a stronger SERS signal. The study would enrich the SERS technique for the fast test of CV in the actual samples.