Direct detection of melamine in infant formula milk powder based on SERS effect of silver thin film coated lotus-leaf

• Main Authors: Hu Yingzi, Yin Zhengyuan, Xiao Guina
• Format: Article
• Language: English
• Published: Academic Journals Center of Shanghai Normal University 2018-02-01
• Series: Journal of Shanghai Normal University (Natural Sciences)
• Subjects: vacuum magnetron sputtering; lotus leaf; silver thin film; surface-enhanced Raman scattering (SERS); melamine; infant formula milk powder
• Online Access: http://qktg.shnu.edu.cn/zrb/shsfqkszrb/ch/reader/view_abstract.aspx?file_no=201801011&flag=1

An efficient surface-enhanced Raman scattering (SERS) substrate has been developed by depositing silver thin film on natural lotus leaf (Ag/lotus-leaf) with vacuum magnetron sputtering method.It was found that the Ag/lotus-leaf substrate showed excellent ability to recognize melamine molecules in infant formula milk powder directly without any sample pretreatment.Quantitative analyses of melamine in milk powder solution at different concentrations were carried out.A good linear relationship was obtained at concentrations ranging from 5 mg/L to 50 mg/L,and the correlation coefficient (<i>R</i>²) of the curve was larger than 0.99.According to the rule of 3<i>&#963;</i>,the limit of detection is estimated to be 1 mg/L.Furthermore,the Ag/lotus-leaf substrate exhibited good uniformity and reproducibility with relative standard deviation (RSD) values of 7.64% and 10.54%.This method was simple,fast,nondestructive,and inexpensive for the detection of melamine in infant formula milk powder.