Study On Detection Of Sex Hormone Residues In Duck Meat By Using SERS

In recent years,with the gradual improvement of people's living standards and the continuous development of animal husbandry in agricultural products,meat,eggs,milk and their products greatly enrich variety of dishes on the table,and have also brought harm to people's health in varying degrees.As an indispensable nutritional and delicious food in life,the proportion of ducks breeding is increasing in the large–scale poultry farming industry.However,news of excessive hormone levels in animal foods has repeatedly emerged.Therefore,it is very important to establish a rapid and accurate method for the determination of hormone residues in duck meat.Because of its high sensitivity,little interference by water and fluorescence and the convenience,surface-enhanced Raman scattering(SERS)has become one of the most commonly used methods in the field of biomedical research and chemical testing in recent years.In this research,Au nanoparticles of different particle sizes were used as SERS enhancement substrate to detect three kinds of sex hormones residues in Sheldrake.The main research contents and conclusions were as follows:(1)A rapid and accurate determination method of testosterone propionate residues in duck meat was established by using SERS with MgSO4 activator and Au nanoparticles of different particle sizes.Firstly,the effects of OTR103 activator and MgSO4 activator on SERS signal of duck meat extract containing testosterone propionate were compared.Then SERS intensities of duck meat extract containing testosterone propionate using Au nanoparticles of different particle sizes were investigated.Finally,the optimal SERS enhancement substrate were Au nanoparticles synthesized by adding 0.8mL sodium citrate and MgSO4 solution,and characterized by the UV-visible absorption spectroscopy.According to the SERS intensities of duck meat extract containing testosterone propionate at 1092cm-1,the optimum detection conditions was determined.Combined with adaptive iteratively reweighted Penalized Least Squares(air-PLS)method,SERS intensities of duck meat extract containing testosterone propionate were analyzed,and the relationship between the residual concentration of testosterone propionate in duck meat extract and the SERS intensities of duck meat extract containing testosterone propionate at 1092cm-1was obtained.The experimental results showed a good linear relationship between the residual concentrations of testosterone propionate in duck meat extract at the range of 1.0 ~20.0mg/L and the SERS intensities at 1092cm-1.The minimum detectable concentration was 1.0mg/L,and the average recovery rate of the samples ranged from 91% to 100%.(2)A rapid and accurate determination method of diethylstilbestrol residues in duckmeat was established by using SERS with MgSO4 activator and Au nanoparticles of different particle sizes.Effects of Au nanoparticles of different particle sizes on SERS intensities of duck meat extract containing diethylstilbestrol were compared.The SERS intensities of duck meat extract containing diethylstilbestrol at 819cm-1were used as the optimization of detection conditions.Finally,Au nanoparticles of the optimum particle sizes were synthesized by adding 0.9mL sodium citrate,and characterized by the UV-visible absorption spectroscopy.The optimum addition amounts of Au nanoparticles,duck meat extract containing diethylstilbestrol and MgSO4 solution were 500?L,5?L and 70?L,respectively,and the best absorption time was 1 min.On the basis of this research,the standard curve equation was established between diethylstilbestrol concentrations in duck meat extract and SERS intensities at 819cm-1.The linear equation was y=185.81x+1260,and the determination coefficient(R2)was 0.9424,and the minimum detectable concentration was 0.5mg/L.Further predictive analysis was done,and R2 between the actual values and the predictive values of the diethylstilbestrol contents in the prediction samples was 0.9690 with RMSEP of 0.7281mg/L and the average recovery rate of sample of 83%~133%(3)A rapid and accurate determination method of 19-nortestosterone residues in duck meat was established by using SERS with MgSO4 activator and Au nanoparticles of different particle sizes.According to the actual situation,effects of Au nanoparticles of different particle sizes on SERS intensities of duck meat extract containing 19-nortestosterone were compared.The SERS intensities of duck meat extract containing 19-nortestosterone at 812cm-1were used as the optimization of detection conditions.Finally,the optimal SERS enhancement substrate were Au nanoparticles synthesized by adding 0.8mL sodium citrate and MgSO4 solution,and characterized by the UV-visible absorption spectroscopy.The optimum addition amounts of Au nanoparticles,duck meat extract containing 19-nortestosterone and MgSO4 solution were 300?L,15?L and 100?L,respectively,and the best absorption time was 1 min.Combined with air-PLS method,SERS intensities of duck meat extract containing 19-nortestosterone were analyzed,and the relationship between the residual concentration of 19-nortestosterone in duck meat extract and the SERS intensities of duck meat extract containing 19-nortestosterone at 812cm-1was obtained.The experimental results showed that a good linear relationship was obtained for detecting19-nortestosterone residues in duck meat extract at the range of 2.0 ~ 20.0mg/L.The minimum detectable concentration was 2.0mg/L.The R2 between the actual values and the predictive values of the 19-nortestosterone contents in the prediction samples was 0.9718,the RMSEP was 0.7984mg/L,and the average recovery rate of sample ranged from 81% to118%.The results indicated that it was feasible to detect testosterone propionate,diethylstilbestrol and 19-nortestosterone residues in duck meat by using SERS technology coupled with self-made enhancement substrate.