Assessment of cisplatin reactivity with peptides and proteins using reverse-phase high-performance liquid chromatography and flameless atomic absorption spectroscopy

Methodology based on gradient elution reverse-phase high-performance liquid chromatography has been developed to permit monitoring of reactions of cisplatin, a noble metal-containing antineoplastic agent, with peptides, polypeptides, and proteins. Such reactions have been implicated in biotransformation of eisplatin. Specificity is provided by both the chromatographic column and the use of on-line uv and off-line atomic absorption spectroscopic detectors placed in series postcolumn. chromatographic conditions were optimized to maximize resolution of nitrogenous components. In some cases, however, resolution of platinum-containing components and those devoid of metal was not possible. This chromatographic overlap could be deconvoluted by sequentially monitoring the eluant with a uv detector (responsive to all proteinaceous material) and on atomic absorption spectrophotometer (specific for platinum detection). This technique has been applied to a kinetic investigation of cisplatin reactivity toward Met-enkephalin.