A new, validated wipe-sampling procedure coupled to LC-MS analysis for the simultaneous determination of 5-fluorouracil, doxorubicin and cyclophosphamide in surface contamination

Abstract

A wipe-sampling procedure followed by a simple liquid chromatography-mass spectrometry method was developed and validated for the simultaneous quantification of three cytotoxic drugs [5-fluorouracil (5FU), doxorubicin and cyclophosphamide (CP)] for the determination of surface contamination. After a solid-phase extraction procedure with wiping filter paper, the separation was performed within 30 min using a gradient mobile phase. The method was validated according to the recommendations of the US Food and Drug Administration. Wiping was performed using Whatman(®) filter paper on different surfaces such as stainless steel, polypropylene and glass. The method was linear, between 10 and 500 ng per wiping sample (i.e., 0.1-5 ng/cm(2)) for 5FU and doxorubicin, and between 1-100 ng per wiping sample (i.e., 0.01-1 ng/cm(2)) for CP. The lower limits of detection and quantification were 5 and 10 ng per wiping sample for 5FU and doxorubicin, and 0.5 and 1 ng per wiping sample for CP. This new sensitive methodology for surface contamination studies was successfully applied on commercial vials and different places in a cancer research hospital. This approach is particularly suitable to assess the risk of occupational exposure to cytotoxic drugs and to optimize the cleaning process, especially for the most toxic molecule studied, CP.