Removal of bacteria from aqueous solution by novel Hydroxyapatite/Zeolite nanocomposite Parisa Maleki b, Bahareh Shoshtari-Yeganeha ,Mojgan Zendehdela* a Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8- 8349, Iran b Department of Biology, Faculty of Science, Arak University, Arak 38156-8- 8349, Iran 1. Introduction Hydroxyapatite (HAp), Ca10 (PO4)6(OH)2, is a class of materials from different origins (mineral, synthetic, and derived from animal and fish bones) [1]. HAp special in nano form has high biocompatibility and bioactivity properties [2]. Zeolites are naturally aluminosilicates which can be also obtained by synthesis and characterized by high internal and external surface areas. Several types of moieties like water and alkaline/alkaline earth metals can be hosted or adsorbed in both natural and synthetic zeolites porous and channels. Herein, we report the synthesis and characterization of hydroxyapatite/Zeolite nanocomposite and in vitro antibacterial activity of these nanocomposites was evaluated against Bacillus subtilis (as Gram-positive bacteria) and Pseudomonas aeruginosa (as Gram-negative bacteria) via utilizing the agar disc diffusion method under anaerobic conditions and compared with standard drugs. 2. Experimental Various aliquots (0.175, 0.350, and 0.700 g) of the prepared hydroxyapatite were initially added to a zeolite gel (NaP). The mixtures were then placed in an autoclave after ageing at 100˚C for 26 h. The three composites with different ratio HAP were synthesized and then filtered and washed with deionized water repeatedly in order to reach pH of 7. For comparison a nanocomposite of Cliniptilolite /HAp was prepared [3]. HAp/Zeolite nanocomposite was then characterized by Fourier transform infrared (FTIR), (XRD), (SEM), (EDAX), (BET) and (TG/DTA). 3. Results and discussion Results suggested that the nanocomposite crystals of HAp were dispersed onto the zeolite external surface and/or encapsulated within the zeolite
