10.1021/acs.jafc.8b05479.s001 Yatai Li Yatai Li Wei Guo Wei Guo Zhaochu Hu Zhaochu Hu Lanlan Jin Lanlan Jin Shenghong Hu Shenghong Hu Qinghai Guo Qinghai Guo Method Development for Direct Multielement Quantification by LA-ICP-MS in Food Samples American Chemical Society 2018 Analysis results agarose-gel standards reference materials gel homogeneity rubber sample supporter novel calibration strategy plasma mass spectrometry Food Samples Direct Multielement Quantification gel standards Method Development LOD analysis throughput Aqueous solutions analyte LA-ICP-MS CRM 2018-12-28 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Method_Development_for_Direct_Multielement_Quantification_by_LA-ICP-MS_in_Food_Samples/7575494 A novel calibration strategy for the accurate determination of essential and toxic elements in both plant-based and animal-based foods was developed by synthesizing spiked agarose gels as matrix-matched external standards and carbon as the internal standard (IS). Aqueous solutions of agarose (4%, m/v) with defined amounts of the analytes were cast on a mold and then dried to form the agarose-gel standards. The spatial distributions of the analytes in the gel were examined using surface- and depth-mapping laser ablation–inductively coupled plasma mass spectrometry (LA-ICP-MS) protocols, and the gel homogeneity was found to be excellent (i.e., relative standard derivation <10%). Recovery of the 19 spiked elements in the gel standards was in the range of 86.9–94.7%. The limits of detection (LODs) ranged from 0.0005 (Rb) to 33.7 μg g<sup>–1</sup> (S). Analysis results were in good agreement with certified values for various certified reference materials (CRMs). Furthermore, a porous rubber sample supporter was developed to improve the analysis throughput by about 3-fold.