Finally, we analyzed synthetic samples that were produced by palladium-catalyzed reactions in our laboratory for unrelated projects. The same stock solutions of these samples were also analyzed by ICP-MS as reference. Table and Figure summarize the results. In general, the current method is not yet optimal for samples containing more than 1000 ppm palladium. The plateaus we observed in Figure are due to the full consumption of RAE (cf. Figure ). Further dilutions or other strategies may be required in the future. Otherwise, the current method is adequately comparable to ICP-MS. Interestingly, unlike the mock samples above, these realworld samples afforded closer data to those produced by ICP-MS analysis. Moreover, there were three samples that must be contaminated with trace palladium because they were synthesized by Pd/C-catalyzed hydrogenation reactions. ICP-MS could not detect the metal, but the current method could. This may be because unlike spiked mock samples, the synthetic compounds, during weeks of storage period, might bind to palladium ions stronger to stabilize and/or solubilize palladium in catalytically active forms. This hypothesis warrants further extensive studies in the future.