Surface-enhanced Raman scattering using flower-like Ag/ZnO as active substrates for the label-free and sensitive detection of rhodamine 6G and melamine

Abstract

The reliable and accurate detection of unauthorized additives in food is significant to prevent health risks. In recent years, surface-enhanced Raman spectroscopy (SERS) with fast, simple, and sensitive capabilities has been widely used for food safety analysis. In order to detect illegally added dye molecule rhodamine 6G and small molecule melamine in food, we have proposed a fast, convenient, and label-free SERS detection technology using flower-like Ag/ZnO as the SERS substrate. The structure and morphology of the flower-like Ag/ZnO were characterized by scanning electron microscopy, energy dispersive spectrometery, transmission electron microscopy, and X-ray diffraction analysis. We investigated the SERS effect and sensitivity of flower-like Ag/ZnO toward rhodamine 6G and melamine. The synergistic effect of flower-like Ag/ZnO provides high SERS activity for the detection of rhodamine 6G and melamine at the lowest detection concentrations of 0.5 ng mL⁻¹ and 1.0 ng mL⁻¹, respectively. Therefore, flower-like Ag/ZnO with good sensitivity and uniformity has potential for improving the detection of illegal food additives.