+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Application of electron energy-loss spectroscopy EELS and energy-filtered transmission electron microscopy EFTEM to the study of mineral transformation associated with microbial Fe-reduction of; magnetite



Application of electron energy-loss spectroscopy EELS and energy-filtered transmission electron microscopy EFTEM to the study of mineral transformation associated with microbial Fe-reduction of; magnetite



Clays and Clay Minerals 59.2



Electron energy-loss spectroscopy (EELS), energy-filtered transmission electron microscopy (EFTEM), and high-resolution transmission electron microscopy (HRTEM) have been applied in mineralogy and materials research to determine the oxidation states of various metals at high spatial resolution. Such information is critical in understanding the kinetics and mechanisms of mineral-microbe interactions. To date, the aforementioned techniques have not been applied widely in the study of such interactions. In the present study the three techniques above were employed to investigate mineral transformations associated with microbial Fe(III) reduction in magnetite. Shewanella putrefaciens strain CN32, a dissimilatory metal-reducing bacterium, was incubated with magnetite as the sole electron acceptor and lactate as the electron donor for 14 days under anoxic conditions in bicarbonate buffer. The extent of bioreduction was determined by wet chemistry and mineral solids were investigated by HRTEM, EFTEM, and EELS. Magnetite was partially reduced and biogenic siderite formed. The elemental maps of Fe, O, and C and red-green-blue (RGB) composite map for residual magnetite and newly formed siderite were contrasted by the EFTEM technique. The HRTEM revealed nm-sized magnetite crystals coating bacterial cells. The Fe oxidation state in residual magnetite and biogenic siderite was determined using the EELS technique (the integral ratio of L3 to L2 ). The integral ratio of L3 to L2 for magnetite (6.29) and siderite (2.71) corresponded to 71% of Fe(III) in magnetite, and 24% of Fe(III) in siderite, respectively. A chemical shift (approximately 1.9 eV) in the Fe-L3 edge of magnetite and siderite indicated a difference in the oxidation state of Fe between these two minerals. Furthermore, the EELS images of magnetite (709 eV) and siderite (707 eV) were extracted from the electron energy-loss spectra collected, ranging from 675 to 755 eV, displaying different oxidation states of Fe in the magnetite and siderite phases. The results demonstrate that EELS is a powerful technique for studying the Fe oxidation-state change as a result of microbial interaction with Fe-containing minerals.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 037001894

Download citation: RISBibTeXText

DOI: 10.1346/ccmn.2011.0590206


Related references

Energy-filtering transmission electron microscopy (EFTEM) and electron energy-loss spectroscopy (EELS) investigation of clay-organic matter aggregates in aquatic sediments. Organic Geochemistry 31(7-8): 735-744, 2000

Electron Energy-Loss Spectrometry (EELS) and Energy-Filtered TEM (EFTEM) Analyses of Organic-Inorganic Nanoparticles. Microscopy and Microanalysis 15(S2): 432-433, 2009

In Situ Environmental Cell-Transmission Electron Microscopy Study of Microbial Reduction of Chromium(VI) Using Electron Energy Loss Spectroscopy. Microscopy and Microanalysis 7(6): 470-485, 2003

Extending energy-filtered transmission electron microscopy (EFTEM) into three dimensions using electron tomography. Microscopy and Microanalysis 9(6): 542-555, 2004

Application of high-angle annular dark field scanning transmission electron microscopy, scanning transmission electron microscopy-energy dispersive X-ray spectrometry, and energy-filtered transmission electron microscopy to the characterization of nanoparticles in the environment. Environmental Science & Technology 37(4): 786-791, February 15, 2003

Electron diffraction of polysiloxane-bound metal complexes using energy-filtered transmission electron microscopy (EFTEM). Journal of Electron Microscopy 48(5): 601-603, 1999

Energy-filtered transmission electron microscopy (EFTEM) of intergrown pyroxenes. American Mineralogist 86(7-8): 814-825, 2001

Demonstration of lanthanum in liver cells by energy-dispersive X-ray spectroscopy, electron energy loss spectroscopy and high-resolution transmission electron microscopy. Journal of Microscopy 223(Pt 2): 133-139, 2006

High-energy-resolution monochromator for aberration-corrected scanning transmission electron microscopy/electron energy-loss spectroscopy. Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences 367(1903): 3683-3697, 2009

Molecular mapping by low-energy-loss energy-filtered transmission electron microscopy imaging. Analytical Chemistry 81(6): 2317-2324, 2009

A new simple method for quantification and locating P and N reserves in microalgal cells based on energy-filtered transmission electron microscopy (EFTEM) elemental maps. Plos One 13(12): E0208830-E0208830, 2018

Electron Microscopy and Electron Energy-Loss Spectroscopy (Eels) of Few-Layer Chemically-Exfoliated Phosphorene Flakes. Microscopy and Microanalysis 24(S1): 470-471, 2018

Em 902 a new transmission electron microscopy for microanalysis with electron spectroscopic imaging and electron energy loss spectroscopy. Ultramicroscopy: 386, 1984

Electron energy-loss spectroscopy (EELS) with a cold-field emission scanning electron microscope at low accelerating voltage in transmission mode. Ultramicroscopy 2019, 2019

A new view on chemistry of solids in solution--cryo energy-filtered transmission electron microscopy (cryo-EFTEM) imaging of aggregating palladium colloids in vitreous ice. Chemistry 6(1): 129-132, 2000