Development and Validation for Assessing the Related Substance of Linezolid by Rp-Hplc Method in Bulk and Injection Formulation

A reverse-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the
estimation of related substances in Linezolid, an oxazolidinone class antibiotic, in both bulk and injection formulations.
The method employed a Symmetry Shield C18 column (150 mm x 4.6 mm, 3.5 µm), with a mobile phase consisting of
potassium dihydrogen phosphate buffer (pH 3.0 adjusted with ammonia and trifluoroacetic acid) and methanol, in a
gradient elution mode. The analyte and impurities were detected at 254 nm. The method was validated as per ICH
Q2(R1) guidelines and demonstrated excellent specificity, sensitivity, accuracy, linearity, and precision. Linearity was
observed over a range of 0.06 to 11.18 ppm (r > 0.999). Recovery studies showed values between 105% and 116%. The
developed method proved robust and stable for both standard and sample solutions, confirming its utility in routine
quality control and stability studies of Linezolid formulations