Ultra-sensitive speciation analysis of inorganic platinum-chloride complexes in platinum-based drugs by HPLC-ICP-MS

This work establishes a hyphenated methodology coupling HPLC with ICP-MS for the determination of platinum chloride complexes as synthetic impurities of platinum-based drugs for the first time. The separation of inorganic platinum-chloride complexes was accomplished in less than 3 min on an anion exchange column with a mobile phase containing 2 mmol L-1 (v : v) HCl. The detection limits were found to be 0.2 mu g L-1 and 0.3 mu g L-1 for potassium hexachloroplatinate (K2PtCl6) and potassium chloroplatinate (K2PtCl4), respectively. Method precision and accuracy were satisfactory at <3% relative standard deviations (RSDs) for 10 mu g L-1 of K2PtCl6 and K2PtCl4, and >90% recoveries for real samples. The method has the advantages of simplicity, rapidity and sensitivity, and provides a basis for quality control of trace impurities in the production process of platinum-based drugs.