The objectives of the study were to develop a simple, reliable, sensitive and accurate high-performance liquid chromatography (HPLC) method for doxofylline pure and pharmaceutical dosage forms. HPLC method was developed for the estimation of doxofylline in pure and marketed, recently expired, and 1-year expired tablet formulations. Chromatographic separation of the drug was achieved on a stainless steel column 25 cm × 4.6 mm, packed with octadecylsilane bonded to porous silica (5 µm), Cosmosil® C18, column using a mobile phase of Potassium dihydrogen orthophosphate buffer: Acetonitrile pH 5.1 (60:40 v/v) at a flow rate of 1-mL/min. The drug eluted was monitored at 274 nm and the retention time of doxofylline was found to be 3.575 minutes, respectively. The validation of developed methods was done according to ICH Q2 (R1) guidelines. The calibration curve was linear over the range of 5 to 50 µg/mL. The correlation coefficient was found to be 0.9943 for doxofylline. The average retention time was found to be 3.538 minutes. The results were reproducible, showing the effectiveness of the system. The plate number was found to be 4909, which is also within the limit, i.e. ≥ 2000 prescribed in I.P. The dissolution studies of all three marketed, recently expired and 1-year expired formulations were carried out by using 0.01 M HCl and the results showed almost a similar rate of release profile and all three formulations accomplished the drug release within the limit. The developed and validated HPLC method offers a precise, accurate, and efficient analytical tool for the determination of doxofylline in pharmaceutical formulations.
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