A fast, economical, precise and accurate free solution capillary electrophoresis method with photodiode array detector was developed and validated for the determination of furosemide in tablets. The separation was achieved by using a fused silica capillary column with (total length of 30.2 cm × 50.0 μm id). The optimum separations conditions were: 2.0 mmol L −1 sodium tetraborate buffer solution, pH 9.3 and 10% methanol; hydrodynamic injection 3.45 kPa/5 s; voltage and temperature set at +25 kV and 25 • C, respectively, and UV detection at 273 nm. The method allowed the quantitative determination of furosemide and showed good linearity (70.0 to 130.0 μg mL −1 ) with a correlation coefficient (>0.99). The migration time was 1.8 min. Accuracy repeatability and intermediate precisions were less than 5.0% and the average recovery, 102.1%. Degradation was tested under neutral, acidic and alkaline hydrolysis, as well as under chemical oxidation, thermal and photodegradation. The method was specific and allowed the detection of three potential degradation products with migration times of 1.3, 2.0, and 2.2 min, respectively under oxidation test. Also, one potential degradation product under acidic hydrolysis (2.0 min). The method can be used in quality control laboratories and also as a stability-indicating method for furosemide in tablets.
K E Y W O R D Scapillary electrophoresis, degradation tests, furosemide, stability-indicating method Article Related Abbreviation: DP, degradation product; FSCE, free solution capillary electrophoresis; PAR, peak area ratios; PDA, photodiode array; STB, sodium tetraborate; WLS, weight loss.Sep Sci plus 2019;2:253-261.