Study of the Thermal Behavior of the Complexation between Norfloxacin Drug with ZrO2+ and UO22+ Ions: TGA and DTG Investigations

The interactions of ZrO2+ and UO22+ ions with the second-generation fluoroquinolone, norfloxacin (NFX) were studied. The obtained complexes were characterized by elemental analysis, electrical conductivity and infrared spectra. The IR spectra of the isolated solid complexes indicated that NFX act as deprotonated bidentate ligand bound to the metal through one of the oxygen atom of the carboxylic group and the ring carbonyl oxygen atom, forming five and six atoms ring with ZrO2+ and UO22+ ions, respectively. The thermal behavior of these two complexes were investigated on the basis of thermogravimetric (TGA) and differential thermogravimetric (DTG) analyses, as well as kinetic thermodynamic parameters estimated from Coats-Redfern and Horowitz-Metzger integral methods. Infrared and thermogravimetric studies reveal the presence of coordinated water molecules. Based on the reported data, the proposed structure of the obtained complexes are {[}ZrO(NFX)(2)]center dot 4H(2)O and {[}UO2(NFX)(2)]center dot 9H(2)O. {[}El-Megharbel S. M, Abdel Majid A. Adam, Moamen S. Refat. Study of the Thermal Behavior of the Complexation between Norfloxacin Drug with ZrO2+ and UO22+ Ions: TGA and DTG Investigations. Life Sci J 2012;9(2):1234-1242]. (ISSN: 1097-8135). http://www.lifesciencesite.com. 184