A low-cost and high precision determination method of 87Sr/86Sr ratios for red wine using thermal ionization mass spectrometry without column separation

Abstract

Thermal ionization mass spectrometry is considered as the “gold standard” for obtaining precise ⁸⁷Sr/⁸⁶Sr isotopic ratios. However, the conventional TIMS technique is laborious because it requires the purification of Sr using expensive and complex resin column techniques to overcome severe ⁸⁷Rb isobaric interference on ⁸⁷Sr and inhibition on ionization of Sr originating from matrix elements. To overcome this issue, we have developed a hydrofluoric acid coprecipitation method specifically designed for red wine samples. This method effectively captures Sr while eliminating ⁸⁷Rb isobaric interference and removing the majority of matrix element inhibition for red wine samples. Notably, our method offers several advantages, including low cost, rapidity, simplicity, and high sample throughput. We have applied this method to analyze nine red wine samples sourced from China, Spain, Chile, Argentina, France, Italy, and Australia. Our method greatly simplified the sample preparation process for red wine samples without compromising the analytical accuracy and precision.