title: Stability-indicating spectrophotometric and densitometric methods for determination of aceclofenac.
abstract: Three methods were developed for the determination of aceclofenac in the presence of its degradation product, diclofenac. In the first method, third-derivative spectrophotometry (D3) is used. The D3 absorbance is measured at 283 nm where its hydrolytic degradation product diclofenac does not interfere. The suggested method shows a linear relationship in the range of 4-24 micrograms mL-1 with mean percentage accuracy of 100.05 +/- 0.88. This method determines the intact drug in the presence of up to 70% degradation product with mean percentage recovery of 100.42 +/- 0.94. The second method depends on ratio-spectra first-derivative (RSD1) spectrophotometry at 252 nm for aceclofenac and at 248 nm for determination of degradation product over concentration ranges of 4-32 micrograms mL-1 for both aceclofenac and diclofenac with mean percentage accuracy of 99.81 +/- 0.84 and 100.19 +/- 0.72 for pure drugs and 100.17 +/- 0.94 and 99.73 +/- 0.74 for laboratory-prepared mixtures, respectively. The third method depends on the quantitative evaluation of thin-layer chromatography of aceclofenac using chloroform:methanol: ammonia (48:11.5:0.5 v/v/v) as a mobile phase. Chromatograms were scanned at 274 and 283 nm for aceclofenac and diclofenac, respectively. The method determined aceclofenac and diclofenac in concentration ranges of 2-10 and 1-9 micrograms spot-1 with mean percentage accuracy of 100.20 +/- 1.03 and 100.14 +/- 0.98 for pure drugs and 99.77 +/- 0.74 and 100.07 +/- 0.78 for laboratory-prepared mixtures, respectively. This method retains its accuracy in the presence of up to 80% degradation product for the studied drug. The suggested procedures were checked using laboratory-prepared mixtures and were successfully applied for the analysis of their pharmaceutical preparation. The validity of the proposed methods was further assessed by applying a standard addition technique. The obtained results agreed statistically with those obtained by the reported method.
authors.affiliation: Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, El-Kasr El-Aini St., ET-11562 Cairo, Egypt.
authors.forename: Y S
authors.initials: YS
authors.lastname: el-Saharty
authors.forename: M
authors.initials: M
authors.lastname: Refaat
authors.forename: S Z
authors.initials: SZ
authors.lastname: el-Khateeb
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis*; D002214:Capsules; D003720:Densitometry / Q000379:methods; D004008:Diclofenac / Q000031:analogs & derivatives* / Q000032:analysis*; D004355:Drug Stability; D005782:Gels; D007267:Injections; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013607:Tablets
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002214:Capsules; D005782:Gels; D013607:Tablets; D004008:Diclofenac; C056498:aceclofenac