title: Simultaneous determination of chloramphenicol, dexamethasone and naphazoline in ternary and quaternary mixtures by RP-HPLC, derivative and wavelet transforms of UV ratio spectra.
abstract: The application of chemometrics-assisted UV spectrophotometry and RP-HPLC to the simultaneous determination of chloramphenicol, dexamethasone and naphazoline in ternary and quaternary mixtures is presented. The spectrophotometric procedure is based on the first-order derivative and wavelet transforms of ratio spectra using single, double and successive divisors. The ratio spectra were differentiated and smoothed using Savitzky-Golay filter; whereas wavelet transform realized with wavelet functions (i.e. db6, gaus5 and coif3) to obtain highest spectral recoveries. For the RP-HPLC procedure, the separation was achieved on a ZORBAX SB-C18 (150×4.6 mm; 5 μm) column at ambient temperature and the total run time was less than 7 min. A mixture of acetonitrile - 25 mM phosphate buffer pH 3 (27:73, v/v) was used as the mobile phase at a flow rate of 1.0 mL/min and the effluent monitored by measuring absorbance at 220 nm. Calibration graphs were established in the range 20-70 mg/L for chloramphenicol, 6-14 mg/L for dexamethasone and 3-8 mg/L for naphazoline (R(2)>0.990). The RP-HPLC and ratio spectra transformed by a combination of derivative-wavelet algorithms proved to be able to successfully determine all analytes in commercial eye drop formulations without sample matrix interference (mean percent recoveries, 97.4-104.3%).
authors.affiliation: Department of Analytical Chemistry and Toxicology, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hanoi, Viet Nam. Electronic address: hoangvd@hup.edu.vn.
authors.forename: Vu Dang
authors.initials: VD
authors.lastname: Hoang
authors.affiliation: Department of Analytical Chemistry and Toxicology, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hanoi, Viet Nam.
authors.forename: Nguyen Thu
authors.initials: NT
authors.lastname: Hue
authors.affiliation: College of Education - Gia Lai, 126 Le Thanh Ton, Pleiku City, Gia Lai Province, Viet Nam.
authors.forename: Nguyen Huu
authors.initials: NH
authors.lastname: Tho
authors.affiliation: Department of Chemistry and Center for Computational Science, Hanoi National University of Education, Viet Nam.
authors.forename: Hue Minh Thi
authors.initials: HM
authors.lastname: Nguyen
mesh_terms: D002138:Calibration; D002701:Chloramphenicol / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D003907:Dexamethasone / Q000032:analysis* / Q000737:chemistry; D009278:Naphazoline / Q000032:analysis* / Q000737:chemistry; D009883:Ophthalmic Solutions; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet; D014466:Ultraviolet Rays; D058067:Wavelet Analysis
chemical_list: D009883:Ophthalmic Solutions; D002701:Chloramphenicol; D003907:Dexamethasone; D009278:Naphazoline
keywords: Derivative; Divisors; Eye drops; RP-HPLC; UV ratio spectra; Wavelet