TY - BOOK AU - Ola Gamal Hussein AU - Eman Saad Elzanfaly , AU - Hala Elsayed Zaazaa , AU - Mohamed Abdelkawy , TI - Analytical study of some pharmaceutical compounds containing heterocyclic rings / PY - 2021/// CY - Cairo : PB - Ola Gamal Hussein , KW - Active Pharmaceutical Ingredients (APIs) KW - Heterocyclic rings KW - Pharmaceutical compounds N1 - Thesis (M.Sc.) - Cairo University - Faculty of Pharmacy - Department of Analytical Chemistry; Issued also as CD N2 - Multicomponent formulations have gained a lot of importance nowadays due to greater patient acceptability, increase potency, multiple action, and quick relief. Simultaneous determination of drugs in combination is an important part in the field of pharmacy as it avoids time of extraction, separation and gets accurate and precise results. Analysis of impurities is very important in the pharmaceutical industry.The possibility of side and toxic effects, and reduced activity of the active substances must be reduced to a minimum. For this reason, different analytical methods were developed to determine Phenazopyridine and Trimethoprim in the presence of Phenazopyridine impurity (2,6-DAP). Most pharmaceutical compounds are subjected to degradation with the subsequent partial or even complete loss of pharmacological activity or the conversion to harmful or toxic substances. A stability indicating procedure may be defined as a procedure that affords selective determination of drug in presence of its degradation products. Thus the development of stability indicating assay has increased enormously. In this thesis, different analytical techniques, namely, spectrophotometry, chemometry, chromatography and voltammetry were developed to determine binary mixture of Phenazopyridine and Trimethoprim in the presence of Phenazopyridine impurity (2,6-DAP).Stability indicating second derivative (2D) spectrophotometry, TLC- densitometry, and voltammetry, were developed to determine Alcaftadine UR - http://172.23.153.220/th.pdf ER -