Biography

Prof. Nita Sahai is in the Department of Polymer Science, University of Akron since August 2011. Prior to this, she obtained tenure and was a Professor in the Department of Geoscience, University of Wisconsin-Madison for 11 years. Prof Sahai’s research focuses on the physical-chemical aspects of cellular and biomolecular interactions at mineral surfaces, in processes relevant to pre-biotic chemistry, the early evolution of life, biomineralization, and bone tissue engineering. Her current and former research is supported by NSF, NASA, and ACS-PRF.

Prof. Sahai has edited Medical Mineralogy and Geochemistry, volume 64 of the Reviews in Mineralogy and Geochemistry Series, Medical Mineralogy and Geochemistry thematic issue of Elements magazine, and has served as Associate Editor for American Mineralogist and Geochemical Transactions. Prof. Sahai has been interviewed on National Public Radio’s “To the Best of Our Knowledge” for her research on the origin of life. Her work on Medical Mineralogy was highlighted in the most widely circulated newspaper in Hungary, and she was also interviewed on Hungarian National Television News during a meeting of the International Mineralogical Society. Prof. Sahai has received the NSF Post-Doctoral Fellowship, the NSF CAREER award, the Romnes Faculty Fellow award from the University of Wisconsin-Madison, holds the Ohio Research Scholar Chair in Biomaterials at the University of Akron, and is a Fellow of the Mineralogical Society of America.

Research Relevant to Origin of Life

The Sahai group’s research focuses primarily on the potential role of mineral surfaces in the evolution of cell surfaces. One major thrust of our research is to examine phospholipid vesicles and bilayers as models of protocell membranes and primitive cell surfaces, interacting with mineral oxide surfaces. Our goal is to order to determine if surface chemical properties of minerals, including surface charge and van der Waals forces, may have influenced the early evolution of the earliest cell surfaces. In a a second study, we are targeting mineral-cell surface interactions at a point in time after bacterial cells with complex cell surfaces, including the energetically expensive process of extra-cellular polymeric substances (EPS) production for biofilm formation. Using biofilm-producing bacterial strains and their isogenic knock-out mutants with defective biofilm producing ability, we are examining the hypothesis that the toxicity of specific mineral nanoparticles may have contributed to the evolution of EPS, and identifying the specific mechanisms for the toxicity of different minerals. We are also examining the potential role of mineral surfaces in pre-biotic chemistry, in order to determine if chiral selection of amino-acids, as seen in carbonaceous condritic meteorites, may have been promoted by adsorption at mineral surfaces.

Relevant Publications

1. Xu J., Hickey, W. J., and Sahai N. (2012) Evolution of bacterial biofilms as armor against mineral toxicity. In review Astrobiology.
2. Oleson T.A., Sahai N., Wesolowski D. J., Dura J. A., Majkrzak C. F., and Giuffre A. J. (2012) Neutron reflectvity study of phosphatidylcholine bilayers on sapphire (110). Accepted for publication, J. Colloid. Interf. Sci.
3. Oleson T.A. and Sahai N. (2010) Interaction energies between oxide surfaces and multiple phosphatidylcholine bilayers from extended DLVO-theory. J. Colloid. Interf. Sci. 352, 316-326.
4. Oleson T. A., Sahai N. and Pedersen J. A. (2010) Electrostatic effects on deposition of multiple phospholpid bilayers at oxide surfaces. J. Colloid. Interf. Sci. 352, 327-336.
5. Xu J., Stevens M. J., Oleson T. A., Last J. A. and Sahai N. (2009) Role of oxide surface chemistry and phospholipid phase on adsorption and self-assembly: Isotherms and Atomic Force Microscopy. J. Phys. Chem. C 113, 2187-2196. Special issue on Physical Chemistry of Environmental Interfaces. INVITED.
6. Oleson T. A. and Sahai N. (2008) Oxide-dependent adsorption and self-assembly of dipalymitoylphosphatidylcholine, a cell-membrane phospholipid: Bulk Adsorption Isotherms. Langmuir 24, 4865-4873.
7. Sahai N. (2002a) Biomembrane phospholipid-oxide surface interactions: crystal chemical and thermodynamic basis. J. Colloid. Interface Sci. 252, 309-319.