Lotfy H.M.Mohamed D.Elshahed M.S.Analytical Chemistry DepartmentFaculty of PharmacyCairo UniversityKasr-El Aini StreetCairo11562Egypt; Pharmaceutical Chemistry DepartmentFaculty of Pharmaceutical Sciences & Pharmaceutical IndustriesFuture University in EgyptCairo11835Egypt; Analytical Chemistry DepartmentFaculty of PharmacyHelwan UniversityEin HelwanCairo11795Egypt; Pharmaceutical Analytical Chemistry DepartmentFaculty of PharmacyOctober University for Modern Sciences and ArtsOctober City 611787Egypt2020-01-092020-01-09201913861425https://doi.org/10.1016/j.saa.2019.05.025PubMed ID 31252262https://t.ly/q28X7ScopusDapagliflozin (DPF) and saxagliptin (SXG) are currently co-formulated in a tablet dosage form which is prescribed to improve glycemic control. The absorption spectra of DPF and SXG were highly overlapped which completely hindered their simultaneous estimation at their ?max 224 nm and 209 nm, respectively. Thus, in this work three smart and simple univariate spectrophotometric methods were originally established and validated for the first time in order to quantitatively estimate DPF and SXG in bulk forms and in combined pharmaceutical formulation without the requirement for any initial separation or treatment. These methods are; factorized zero order method (FZM), factorized derivative method (FDM) and factorized ratio difference method (FRM). These methods were capable of determining DPF and SXG over the range of 2.5�50.0 ?g/mL and 2.5�60.0 ?g/mL, respectively. All the developed methods are based on a novel and unique approach for the spectral recovery of unresolved spectra named; factorized response spectrum (FRS). The exclusivity of the FRS originates from its ability to completely resolve the cited drugs in the mixture and retrieve their original spectra. Selectivity of all proposed methods was assessed by comparing the obtained results of the mixture analysis with those of the pure powdered drugs. Validation of the newly developed methods was applied as recommended by the ICH demonstrating acceptable accuracy and precision. In general, these methods could be effectively employed for the routine quality control investigation of bulk materials and available market formulations. � 2019 Elsevier B.V.EnglishDapagliflozinFactorized derivative methodFactorized ratio difference methodFactorized response spectrumFactorized zero order methodSaxagliptinControlled drug deliveryMixturesSpectrophotometersSpectrophotometryDapagliflozinDerivative methodRatio differencesResponse spectraSaxagliptinZero-order methodsQuality control2-(3-(4-ethoxybenzyl)-4-chlorophenyl)-6-hydroxymethyltetrahydro-2H-pyran-3,4,5-trioladamantanebenzhydryl derivativedipeptidedipeptidyl peptidase IV inhibitorglucosidesaxagliptindrug combinationlimit of detectionproceduresspectrophotometrytabletAdamantaneBenzhydryl CompoundsDipeptidesDipeptidyl-Peptidase IV InhibitorsDrug CombinationsGlucosidesLimit of DetectionSodium-Glucose Transporter 2 InhibitorsSpectrophotometryTabletsArticlehttps://doi.org/10.1016/j.saa.2019.05.025PubMed ID 31252262