Spectrophotometric strategies for the analysis of binary combinations with minor component based on isoabsorptive point's leveling effect: An application on ciprofloxacin and fluocinolone acetonide in their recently delivered co-formulation

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 219; pp. 186 - 194
• Main Authors: Obaydo, Reem H., Alhaj Sakur, Amir
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 05.08.2019
• Subjects: Amplitude modulation method; Area under the curve; Ciprofloxacin hydrochloride; Derivative; Fluocinolone acetonide; Isoabsorptive point; Minor component; Isoabsorptive point; Fluocinolone acetonide; Area under the curve; Derivative; Amplitude modulation method; Ciprofloxacin hydrochloride; Minor component
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2019.04.036

Comparative study of the spectrophotometric strategies utilizing the isoabsorptive point present in overlapped absorption spectra of ciprofloxacin and fluocinolone acetonide in their recently delivered co-formulation, was presented. Four spectrophotometric approaches were developed, dependent on the determination of the leveling effect of isoabsorptive point in their zero order absorption spectra or its manipulated form ratio spectra as it retains an isosbestic point. The proposed strategy was based on determination of the total concentrations of the proposed drugs at iso-point, either via zero order or ratio spectra, while one of the recommended methods determined the concentration of the major component, so the concentration of the minor component was obtained by differentiation. The first, second and third methods are utilizing isoabsorptive point at zero order absorption spectrum to quantify total concentration of the cited component, while the major component could be selectively determined using either absorbance at its maxima (IsoPD0-D0max), or area under the peak method (IsoPD0-AUC), or first derivative technique (IsoPD0-D1). The fourth method is ratio manipulated isoabsorptive point in ratio spectrum, namely the amplitude modulation method (AM), using an unified regression equation for the total and major component concentrations, separately. The four methods were applied practically for the analysis of the binary mixtures of ciprofloxacin hydrochloride (CIP) and fluocinolone acetonide (FLU) in a recently otic solution form in challengeable ratio12:1respectively, without the need of any previous stages such as separation, dilution or standard addition. The methods were successfully validated as per ICH guidelines. The outcomes data gained from those submitted techniques were statistically assimilated with official ones. However, no radical differences were noticed. [Display omitted] •Spectrophotometric analysis of a newly approved combination of Ciprofloxacin and Fluocinolone•This combination has no analytical methods until now and present in very challengeable ratio•Comparative study of different spectrophotometric strategies based on isoabsorptive point’s leveling effect.•Coupling of Isoabsorptive point with area under the peak methods is considered as a new approach of isoabsorptive point technique.•All methods are taken for as an eco-friendly method of analysis with minimum manipulation steps.•No need for purchasing a specialized program and easily applied in quality control laboratories.