Univariate and multivariate spectrophotometric methods for simultaneous determination of avobenzone and octinoxate in pure form and in cosmetic formulations: A comparative study

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 206; pp. 37 - 47
• Main Authors: Al Alamein, Amal Mahmoud Abou, Elwy, Hanan Mohamed, El-Din, Safaa Hussein Salah
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 05.01.2019
• Subjects: Analysis of Variance; Avobenzone; Chemometry; Cinnamates - analysis; Cosmetics - analysis; Cosmetics - chemistry; Limit of Detection; Linear Models; Octinoxate; Propiophenones - analysis; Reproducibility of Results; Spectrophotometry; Spectrophotometry - methods; Sunscreening Agents - analysis; UV filters; UV filters; Avobenzone; Octinoxate; Spectrophotometry; Chemometry
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2018.07.073

Simple, economic and precise spectrophotometric and chemometric techniques were used to determine UV filters namely; avobenzone (AV) and octinoxate (OCT) simultaneously in pure form and in cosmetic formulations in concentration range (2–10 μg·mL−1) for both drugs. The spectrophotometric technique includes five different methods; Method (A) is first derivative (D1) spectrophotometry at 380.6 nm for AV and 276.2 nm for OCT, Method (B) is first derivative of ratio spectra (DR1) at 352.8 nm for AV and 312.2 nm for OCT, Method (C) is ratio difference spectrophotometry (RD) at 356 nm and nm 347.2 nm for AV and at 311.6 nm and 281 nm for OCT, Method (D) is mean centering spectrophotometry (MCR) at 356 nm for AV and 301.8 nm for OCT and method (E) is modified Vierordt's method which involves absorbance measurement at 358 nm for AV and 309.2 nm for OCT and determination of the concentration of x and y from the two simultaneous equations. The chemometric technique includes multivariate calibration methods; partial least squares (PLS) and principle component regression (PCR) using the absorption spectra. The proposed methods were applied for determination of (AV) and (OCT) simultaneously in pure form and in cosmetic formulations. These methods were validated according to ICH guidelines. [Display omitted] •Analysis of the studied UV filters is of great impact in health care formulations.•Novel spectrophotometric techniques for determination of both drugs in a mixture•The developed methods are selective in resolving binary mixture overlapped spectra.•The methods are easily applied in QC laboratories.•The developed methods can be applied in pure form and in cosmetic formulations.