Study on SERS Detection of Ethyl Carbamate in Grape Spirit
ZHAO Jing-rui1, WANG Ya-min1, YUAN Yu-xun1, YU Jing1, ZHAO Ming-hui1, DONG Juan1, 3, SUN Jing-tao1, 2, 3, 4*
1. Food College of Shihezi University, Shihezi 832000, China
2. Key Laboratory of Xinjiang Phytom Edicine Resource and Utilization, Ministry of Education, Shihezi 832003，China
3. Key Laboratory of Agricultural Product Processing and Quality Control of Specialty, Shihezi 832000, China
4. Key Laboratory for Food Nutrition and Safety Control of Xinjiang Production and Construction Corps, Shihezi 832000, China
Abstract：Ethyl carbamate，A group 2A carcinogen, is commonly found in fermented foods such as grape, soy sauce, and pickles. Due to its toxicity and carcinogenicity, it can accumulate in organisms and produce a variety of lesions and has become a potential threat to the modern food processing industry. The traditional detection method of ethyl carbamate has the disadvantages of a complicated sample pretreatment process, long analysis time, expensive equipment, high requirements for testers, and the inability to detect large samples quickly. Therefore, there is an urgent need to develop a rapid, accurate, and efficient method for urethane detection. Surface-enhanced Raman spectroscopy (SERS) technology has the characteristics of high sensitivity, high selectivity, resistant photo bleaching, short response time, and non-destructive. SERS overcomes the problems of Raman spectroscopy, such as weak scattering signals and large background interference, and can realize the rapid qualitative and quantitative detection and analysis of trace substances, showing good application prospects in the territory of food safety detection. In this study, surface-enhanced Raman spectroscopy was used to detect the content of ethyl carbamate in grape spirit rapidly. Silver nanosphere silicon cone array and gold-silver alloy nanosphere silicon cone array were used as SERS substrates. The effects of SERS substrate structure, mixing time, storage time, and excitation wavelength on Raman scattering signals were investigated, and the optimal SERS substrate was determined. The results show that good Raman signals can be obtained when the excitation wavelength is 785 nm, the mixing time is 60 min, and the thickness of silver nanoparticles is 10 nm using Ag-Au/SiNCA as the SERS-enhanced substrate. The characteristic peak position of 1 442 cm-1for quantitative analysis of ethyl carbamate in grape spirit was determined using density functional theory, and a linear equation was established between the peak intensity of the characteristic peak at 1 442 cm-1and the EC concentration. The equation has a good linear relationship in the concentration range of 1×10-3～1×10-8 mol·L-1, and the coefficient of determination R2=0.821 3. The recovery rate of the method is between 83.06% and 110.00%, and the minimum detection limit can reach 3.28×10-8 mol·L-1. This detection method is very simple and quick to operate, and analyze. If this method applies EC in grape spirit, an effective and rapid detection method can be provided with ideas and references.
