title: Multivariate least squares regression applied to the spectrophotometric analysis of manidipine and its main photoproduct.
abstract: The simultaneous quantitative assay of 1,4-dihydropyridine calcium antagonist manidipine and its main photodegradation by-product has been defined by using a multivariate calibration on UV spectra based on a classical least squares regression. Optimization of the procedure was achieved by means of a calibration model using suitable wavelength ranges singled out from a fractionation scheme thereat defined. Recovery values of 99 and 96% for the drug and the by-product, respectively, were found either in appropriately prepared mixtures and commercial formulations. Quantification limit for the photoproduct concentration was estimated as 1.0% for the reference samples.
mesh_terms: D002121:Calcium Channel Blockers / Q000737:chemistry* / Q000528:radiation effects*; D004095:Dihydropyridines / Q000737:chemistry* / Q000528:radiation effects*; D004355:Drug Stability; D016018:Least-Squares Analysis; D008027:Light; D015999:Multivariate Analysis; D009578:Nitrobenzenes; D010777:Photochemistry; D010879:Piperazines; D013053:Spectrophotometry
chemical_list: D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D009578:Nitrobenzenes; D010879:Piperazines; C054218:manidipine