title: Determination of dexamethasone and two excipients (creatinine and propylparaben) in injections by using UV-spectroscopy and multivariate calibrations.
abstract: The use of multivariate spectrophotometric calibration for the simultaneous determination of dexamethasone and two typical excipients (creatinine and propylparaben) in injections is presented. The resolution of the three-component mixture in a matrix of excipients has been accomplished by using partial least-squares (PLS-1). Notwithstanding the elevated degree of spectral overlap, they have been rapidly and simultaneously determined with high accuracy and precision (comparable to the HPLC pharmacopeial method), with no interference, and without resorting to extraction procedures using non-aqueous solvents. A simple and fast method for wavelength selection in the calibration step is used, based on the minimisation of the predicted error sum of squares (PRESS) calculated as a function of a moving spectral window.
authors.affiliation: Laboratorio de Control de Calidad de Medicamentos, Cátedra de Química Analítica I, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Ciudad Universitaria, Paraje El Pozo, 3000, Santa Fe, Argentina.
authors.forename: M S
authors.initials: MS
authors.lastname: Collado
authors.forename: J C
authors.initials: JC
authors.lastname: Robles
authors.forename: M
authors.initials: M
authors.lastname: De Zan
authors.forename: M S
authors.initials: MS
authors.lastname: Cámara
authors.forename: V E
authors.initials: VE
authors.lastname: Mantovani
authors.forename: H C
authors.initials: HC
authors.lastname: Goicoechea
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D003404:Creatinine / Q000032:analysis*; D003907:Dexamethasone / Q000032:analysis*; D007202:Indicators and Reagents; D015999:Multivariate Analysis; D010226:Parabens / Q000032:analysis*; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007202:Indicators and Reagents; D010226:Parabens; D003907:Dexamethasone; D003404:Creatinine; C006068:propylparaben