title: Voltammetric, spectrofluorimetric and spectrophotometric methods to determine flufenamic acid.
abstract: Simple, rapid and sensitive voltammetric, spectrofluorimetric and spectrophotometric methods for determination of flufenamic acid (FF) in bulk powder and capsule dosage form are presented. The methods are based on the cyclisation reaction of FF with concentrated sulphuric acid to produce the corresponding acridone derivative. The voltammetric method is based on the adsorptive stripping differential pulse (DP) technique. The acridone derivative is determined over the concentration range of 8-60 ng ml(-1) using adsorptive preconcentration at the hanging mercury drop electrode (HMDE). The lower detection limit was found to be 1.02 ng ml(-1). The fluorimetric and spectrophotometric methods are based on the measurement of the fluorescence intensity at 450 nm (lambda(ex) = 400 nm)and peak-to-peak measurements of the first- (D1) and second-derivative (D2) curves, respectively. Beer's law is obeyed over the concentration ranges of 2-20 ng ml(-1) and 0.2-8.0 microg ml(-1) for the fluorimetric and spectrophotometric measurements, respectively. The three methods were proved to be accurate and reproducible as indicated by a relative standard deviation of <2%.
authors.affiliation: Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, University of Alexandria, Egypt. pharmacy.alex.univ.mac@cns-egypt.com
authors.forename: S M
authors.initials: SM
authors.lastname: Sabry
authors.forename: H
authors.initials: H
authors.lastname: Mahgoub
mesh_terms: D000327:Adsorption; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis* / Q000737:chemistry; D002138:Calibration; D002214:Capsules; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D004355:Drug Stability; D004563:Electrochemistry / Q000295:instrumentation; D000431:Ethanol / Q000737:chemistry; D005439:Flufenamic Acid / Q000032:analysis* / Q000737:chemistry; D011208:Powders; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002214:Capsules; D011208:Powders; D000431:Ethanol; D005439:Flufenamic Acid