Development and validation of simple colorimetric methods for assessing norfloxacin in pure form, in pharmaceutical products and in biological material.

Two straightforward, affordable, accurate, and spectrophotometric techniques gross developed to assess norfloxacin, formulations, and biological samples. The oxidation of norfloxacin will be done in technique (A) in acid solution with help of Fe(III). A wavelength of 511 nm with a correlation coefficient of 0.9879 was produced by the resulting Fe(II) coupled with 1,10-phenanthroline and the red colour complex. A uniform absorbance ranging from 1 to 30 µg/mL was discovered. Similarly, in procedure (B), in an acidic medium, Ce(IV) was added to norfloxacin. After reacting with a specific amount of methyl orange, the residual Ce(IV) is then determined. An absorbance measurement at 508 nm and a correlation coefficient of 0.9966 indicate a straight-line relationship between the two variables for concentration range is 1-15 µg/mL. The procedures were developed after a careful analysis of the several elements that influence the reaction process. After calculations, the LOD (limits of detection) and LOQ (limit of quantification) were determined to be 1.098 and 1.111 µg/mL for method A and 2.875 and 3.368 µg/mL for method B respectively. The method B has also been applied for the determination of norfloxacin in spiked human plasma and urine samples. The percentage recoveries ranged from 98.74 to 103.43% and from 98.17 to 100.85% for plasma and urine samples, respectively. Proposed techniques have been successfully used for the examination of biological fluids, formulations for medicines as well as pure norfloxacin following statistical validation through recovery studies.