[Determination of 13 elements in food by microwave plasma-atomic emission spectrometry].

ABSTRACT

OBJECTIVE: A novel method for quantitative analysis of multi-elements (Ca, Fe, K, Na, Cu, Mn, Zn, Mg, Ni, Sr, Cr, Cd and Co) in food was established by using microwave plasma-atomic emission spectrometry (MP-AES). METHODS: Samples were digested with HNO3 and H2O2 followed by dilution with ultrapure water to 25 mL (g), and then analyzed directly by MP-AES. RESULTS: In the optimal conditions, the linear calibration curve was established for each element, and the linear regression correlation coefficient was more than 0.9999. The limit of detection (LOD) of these multi-elements varied from 0.04 µg/kg to 3.90 µg/kg. The spiked recovery was between 89.8% and 110.4% . The relative standard deviation of precision measurement was between 1.33% and 3.85%. The accurate and reliable results were obtained for validation of the MP-AES method with food reference material according to the standard reference materials (Nist 1549, Nist 1567, Nist 1568 and Nist 1570) and national standard (GBW08501 and GBW10051), and the measured values were in good agreement with the certified values. CONCLUSION: The established method is accurate, simple, fast, reproducible and environmentally friendly.