Abstract.1 Cis-diaminedichloroplatinum(II), also known as cisplatin, has been quantified by use of inductivelycoupled plasma. We measured cisplatin indirectly by determining the platinum concentration in the samples. We focus on the determination of Pt from cisplatin in water. We demonstrate that the total concentration of the drug can be quantified through the content of platinum with acceptable linearity, precision, repeatability, accuracy, limit of detection and limit of quantification. Our method is applicable among others for monitoring quality of control samples for cisplatin regulatory submissions and for determination of the cisplatin release profiles in biomarker implants in vitro.