Study on the determination of 18 elements in chocolate by inductively coupled plasma mass spectrometry

Samples of chocolate were digested by microwave digestion,and trace elements amounts of Na,Mg, P,K,Ca,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Se,Sr,Mo and Pb in sample solutions were determined by inductively coupled plasma mass spectrometry(ICP-MS). HNO3 +H2O2 were used to achieve the complete decomposition of the organic matrix in a closed - vessel microwave oven . Working parameters of the instrument were optimized. Results showed that the relative standard deviation(RSD) was less than 4.6% for all the elements, and the recovery was 89.60% ~106.12% by adding standard recovery experiment. This method was simple, sensitive,precise and could perform simultaneous multi -elements determination of chocolate,which could satisfy the sample examination request and provide scientific rationale for determining inorganic elements of chocolate.