Lotfy H.M.Saleh S.S.Hassan N.Y.Salem H.Analytical Chemistry DepartmentFaculty of PharmacyCairo UniversityKasr-El AiniCairo11562Egypt; Pharmaceutical Chemistry DepartmentFaculty of Pharmaceutical Sciences and Pharmaceutical IndustriesFuture University in Egypt (FUE)Cairo12311Egypt; Analytical Chemistry DepartmentFaculty of PharmacyOctober University for Modern Sciences and Arts (MSA)6th October11787Egypt; Analytical Chemistry DepartmentFaculty of PharmacyDeraya UniversityMiniaEgypt2020-01-092020-01-09201513861425https://doi.org/10.1016/j.saa.2015.06.103PubMed ID 26163786https://t.ly/q27xEScopusMSA Google ScholarNovel spectrophotometric methods were applied for the determination of the minor component tetryzoline HCl (TZH) in its ternary mixture with ofloxacin (OFX) and prednisolone acetate (PA) in the ratio of (1:5:7.5), and in its binary mixture with sodium cromoglicate (SCG) in the ratio of (1:80). The novel spectrophotometric methods determined the minor component (TZH) successfully in the two selected mixtures by computing the geometrical relationship of either standard addition or subtraction. The novel spectrophotometric methods are: geometrical amplitude modulation (GAM), geometrical induced amplitude modulation (GIAM), ratio H-point standard addition method (RHPSAM) and compensated area under the curve (CAUC). The proposed methods were successfully applied for the determination of the minor component TZH below its concentration range. The methods were validated as per ICH guidelines where accuracy, repeatability, inter-day precision and robustness were found to be within the acceptable limits. The results obtained from the proposed methods were statistically compared with official ones where no significant difference was observed. No difference was observed between the obtained results when compared to the reported HPLC method, which proved that the developed methods could be alternative to HPLC techniques in quality control laboratories. � 2015 Elsevier B.V. All rights reserved.EnglishAmplitude modulationArea under the curveH-pointPrednisolone acetateSodium cromoglicateTetryzolineAmplitude modulationBinary mixturesGeometryMixturesModulationQuality controlSodiumSpectrophotometersVolatile fatty acidsArea under the curvesH-pointPrednisoloneSodium cromoglicateTetryzolineSpectrophotometryantiinfective agentantiinflammatory agentdecongestive agentdrugimidazole derivativeofloxacinprednisoloneprednisolone acetatetetryzolineanalogs and derivativescomputer analysisproceduresspectrophotometryAnti-Bacterial AgentsAnti-Inflammatory AgentsComputing MethodologiesImidazolesNasal DecongestantsOfloxacinPharmaceutical PreparationsPrednisoloneSpectrophotometryArticlehttps://doi.org/10.1016/j.saa.2015.06.103PubMed ID 26163786