title: Synthesis and characterization of monodispersed orthorhombic manganese oxide nanoparticles produced by Bacillus sp. cells simultaneous to its bioremediation.
abstract: A heavy metal resistant strain of Bacillus sp. (MTCC10650) is reported. The strain exhibited the property of bioaccumulating manganese, simultaneous to its remediation. The nanoparticles thus formed were characterized and identified using energy dispersive X-ray analysis (EDAX), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (PXRD) and atomic force microscopy (AFM). When the cells were challenged with manganese, the cells effectively synthesized nanoparticles of average size 4.62±0.14nm. These were mostly spherical and monodispersed. The ex situ enzymatically synthesized nanoparticles exhibited an absorbance maximum at 329nm. These were more discrete, small and uniform, than the manganese oxide nanoparticles recovered after cell sonication. The use of Bacillus sp. cells seems promising and advantageous approach. Since, it serves dual purposes of (i) remediation and (ii) nanoparticle synthesis. Considering the increasing demand of developing environmental friendly and cost effective technologies for nanoparticle synthesis, these cells can be exploited for the remediation of manganese from the environment in conjunction with development of a greener process for the controlled synthesis of manganese oxide nanoparticles.
authors.affiliation: Enzyme and Microbial Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110 016, India.
authors.forename: Arvind
authors.initials: A
authors.lastname: Sinha
authors.forename: Vidya Nand
authors.initials: VN
authors.lastname: Singh
authors.forename: Bodh Raj
authors.initials: BR
authors.lastname: Mehta
authors.forename: Sunil Kumar
authors.initials: SK
authors.lastname: Khare
mesh_terms: D001407:Bacillus / Q000378:metabolism*; D003470:Culture Media; D052918:Environmental Restoration and Remediation / Q000379:methods*; D017895:Manganese Compounds / Q000138:chemical synthesis* / Q000378:metabolism; D053768:Metal Nanoparticles; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D010087:Oxides / Q000138:chemical synthesis* / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D003470:Culture Media; D017895:Manganese Compounds; D010087:Oxides; C027424:manganese oxide