Multiple sensitive eco‐friendly analytical approaches for the determination of two fourth‐generation fluoroquinolones: Application to stability study and content uniformity testing

Abstract

Multiple sensitive eco-friendly analytical techniques were applied for the assessment of two important fourth-generation fluoroquinolones namely, gemifloxacin (GFX), and gatifloxacin (GTF). GFX, which is utilized as an essential adjunct therapy for the management of pneumonia in SARS-CoV-2 was determined by green indicating micellar liquid chromatographic in authentic powder and dosage forms. The separation was performed by using a reversed-phase C18 column; the micellar mobile phase comprised of 12.5% n-propanol, 0.15 M sodium lauryl sulfate, and 0.3% triethylamine in 0.02 M O-phosphoric acid adjusted to pH 3.0 and pumped at 1 ml/min flow rate and detected at 266 nm by UV detection. The method was linear over the range of 4.0–90 μg.ml−1 with a recovery percentage of 99.81 ± 0.69. The acidic degradation behavior of GFX along with the kinetic investigation was evaluated as recommended by ICH-stress conditions. The separation of the degradation product was performed in good elution time (less than 8 min), and the suggested technique has a good reproducibility (R.S.D. less than 1.0%) and provides an excellent resolution (Rs = 4.5) between GFX and its degradation product. Concerning the second drug, GTF, simple, extremely sensitive, and accurate spectrofluorimetric and spectrophotometric techniques were adopted for the determination of the drug in its pharmaceutical preparations. The suggested approaches utilize the concept of complex formation with eosin Y in an aqueous buffered solution. Regarding the spectrophotometric method (method I), the binary complex has a maximum absorption at 544 nm, while for spectrofluorimetric determination (method II) the formed complex was recorded at λem 491 nm after excitation at 286 nm. For both approaches, variables affecting the formation of the binary complexes were extensively investigated and optimized. The suggested techniques were shown to be rectilinear across the concentration range of 0.5–8 and 0.05–1 μg.ml−1, respectively, with recovery percentages of 100.34 ± 0.85 and 99.90 ± 0.81 for method (I) and method (II), respectively. In compliance with ICH guidelines, the analytical performance of the suggested techniques was thoroughly validated. Moreover, uniformity testing was also applied successfully for the evaluation of GFX by the proposed micellar liquid chromatographic method. To ensure the proposed methodology's greenness, The AGREE calculator software was adopted and the results obtained revealed an excellent greenness of the proposed approaches.