A new stability indicating HPLC and LC-APCI-MS methods for the estimation of flucytosine in pharmaceutical dosage forms

Flucytosine is an anti-fungal agent which acts against mycotic infections. The anti-mycotic activity of Flucytosine is due to its conversion in to 5-fluoro uracil. In the present study the authors have proposed a new stability indicating isocratic RP-HPLC as well as LC-APCI-MS methods for the estimation of Flucytosine and the methods are validated as per ICH guidelines. Thermo scientific - TSQ Quantis with Vanquish HPLC coupled with MS was employed for the study with Simpack C18 (250 mm × 4.6 mm × 5μm) column. A triple quadrupole mass spectrometer with atmospheric pressure chemical ionization (APCI) source, running in the positive mode (as well as negative mode) was used for the detection. A mixture of 0.1% Acetic acid: Methanol was used as mobile phase (50:50, v/v) (UV detection at 235 nm). A wide linearity concentration range 1.0-120 μg/ml was observed and the method is found to be precise and accurate and can be used for the estimation of marketed formulations. Stress degradation studies were performed and the method is found to be selective and specific.