A Validated Uplc-Ms/Ms Method for the Quantification of Cyclophosphamide in Human Plasma: Application to Therapeutic Drug Monitoring in Cancer Patients

Abstract

A rapid, simple, sensitive, and highly specific method has been developed for determination of Cyclophosphamide in human plasma. It is in a class of medication called alkylating agents used to treat various forms of cancer. The analytical procedure involves a liquid-liquid extraction method using Cyclophophamide-D8 as an internal standard. Chromatographic separation was carried out on a reversed phase Agilent Zorbax, XDB (150mm x 4.6mm, 5μm) column. Cyclophosphamide and Cyclophophamide-D8 were detected with proton adducts at (262.90/141.60) and (270.90/148.60) respectively in multiple reaction monitoring (MRM) positive mode. The method was linear over the concentration range of 20–15000 ng mL−1. The lower limit of detection (LLOD) Cyclophosphamide was 20 ng mL−1. The method was shown to be precise with the average within-run and between-run variations of 2.78 to 11.13% and 2.82 to 10.70%, respectively. The mean recoveries of Cyclophophamide from human plasma by the developed method were 100.1-101%. This validated method has been successfully applied for routine therapeutic drug monitoring of Cyclophosphamide in cancer patients.