Accurate determination of silver nanoparticles in animal tissues by inductively coupled plasma mass spectrometry

• We performed detailed optimization of microwave assisted digestion procedure of animal tissue used prior to Ag determination by ICP-MS.
• We provide basic equilibrium calculations to give theoretical explanation of results from optimization of tested mineralization mixtures.
• Results from method validation that was done by analysis of several matrix CRMs are presented.

This study examined recoveries of silver determination in animal tissues after wet digestion by inductively coupled plasma mass spectrometry. The composition of the mineralization mixture for microwave assisted digestion was optimized and the best recoveries were obtained for mineralization with HNO3 and addition of HCl promptly after digestion. The optimization was performed on model samples of chicken meat spiked with silver nanoparticles and a solution of ionic silver. Basic calculations of theoretical distribution of Ag among various silver-containing species were implemented and the results showed that most of the silver is in the form of soluble complexes AgCl2− and AgCl32 − for the optimized composition of the mineralization mixture. Three animal tissue certified reference materials were then analyzed to verify the trueness and precision of the results.