A new chemiluminescence method for determination of cytosine arabinoside in pharmaceutical preparations

Abstract

A novel chemiluminescence (CL) system was established for the determination of cytosine arabinoside (Ara- C) in pharmaceutical preparations. It was showed that a clear CL signal was observed when Eosin Y mixed with Fenton reagent. The CL intensity was decreased significantly when Ara-C was added to the reaction system and partially scavenged the hydroxyl radicals in the solution. The extent of decrease in the CL intensity had a good stoichiometrical relationship with the Ara-C concentration. Based on this, we developed a new method for the determination of Ara-C using a flow injection analysis (FIA) technique with CL detection. Under the optimal conditions, the linear range of Ara-C concentration was 6.0 × 10-9 ~ 1.0 × 10-7 mol/L (R = 0.9982) with a detection limit of 7.6 × 10-10 mol/L (S/N=3) , the RSD was 5.6% for 6.0 × 10-8 mol/L Ara- C (n = 11). The method was successfully applied to the determination of Ara-C in injection samples. The possible chemiluminescence reaction mechanism was discussed.