Simple and sensitive determination of the new antitumor drug CKD-602 in human plasma by liquid chromatography

A simple and sensitive high-performance liquid chromatographic with fluorescence detection method has been developed and validated for the determination of the new antitumor agent CKD-602 in human plasma. Plasma proteins were precipitated with methanol and the samples were acidified with 7% (v/v) perchloric acid. The supernatants were analyzed by HPLC using a Capcell Pak C18 UG120 column and a mixture of methanol–0.1 M hexane-1-sulfonic acid in methanol–0.01 M TEMED in water at pH 6.0 (40:1:59, v/v) as the mobile phase. The lower limit of quantification was 0.2 ng/ml using 200 μl plasma samples. Mean within-run precision and between-run precision at six tested concentrations (0.2–400 ng/ml) were ≤10% and mean accuracy was ≤15%. Stability studies showed that CKD-602 is stable in both plasma and methanol extracts for at least 3 months at −30 °C. The described method was used for the pharmacokinetic analysis of CKD-602 during clinical phase I studies, in patients with solid tumors.