Authors: JinHua Li YongXin Pan QingSong Liu HuaFeng Qin ChengLong Deng RenChao Che XinAn Yang
Publish Date: 2009/09/04
Volume: 55, Issue: 1, Pages: 38-44
Abstract
The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment as well as novel nanobiomaterials in biotechnological and biomedical applications We carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB1 whole cells and isolated magnetosomes Results revealed that AMB1 synthesized singledomain magnetite magnetosomes which are arranged in the form of linear fragmental chain The distinct differences of magnetic properties between these two samples can be faithfully interpreted in terms of spatial arrangement of magnetosomes and magnetostatic interaction For the whole cells the strong intrachain interactions and weak interchain interactions generate behaviors of noninteracting uniaxial singledomain particles Its δratio is 30 and passes the Moskowitz test In contrast the isolated magnetosome sample has reduced values of coercivity and δratio 15 due to increasing threedimensional magnetostatic interactions and collapse of magnetosome chains These observations provide useful insights into applications of the biogenic magnetite magnetosomes in magnetic nanomaterials and magnetofossils in the paleomagnetic and environmental magnetism
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