Asher Schmidt

Asher Schmidt

Associate Professor
Solid state NMR techniques as molecular-functional eyes of materials interfaces and surfaces: Bioorganic-inorganic interfaces in biomineralization and biomimetics; understanding function-tailored materials properties (biogenic and synthetic). Specific binding by inorganic and organic mesoporous materials; understanding the molecular details that govern determine reactivity.

Methodology: Solid state NMR is a most powerful non-destructive spectroscopy to study the composite characteristics of solid functional materials. Solids NMR provides molecular-structural eyes to probe non-abundant and often disordered regions that occur at interfaces or surfaces of such materials; although scarce, these regions are known to strongly affect the materials’ properties and functionality. Our lab has three dedicated, fully equipped solid state MAS NMR spectrometers (300, 300, 500 MHz) and a wet lab. High-Resolution Solid-State NMR techniques are applied in the following two areas.

Molecular strategies and mechanisms in biomineralization and biomimetics: Biomineralization is a process by which inorganic materials (shell, exoskeleton, tooth, bone) are produced by organisms ranging from unicellular to mammalians. The organisms employ bioorganic molecules and inorganic ions to fully control the microscopic (molecular) and macroscopic (stability, strength) properties of the bulk biomineral. We focus on the molecular level understanding of the functional roles of inorganics and bioorganics during mineral synthesis and after that once occluded in the bulk matrix, and how they serve to imprint permanent and transient properties within the biomineral. We apply our studies to both intact biogenic systems (coccolithophores, crayfish gastroliths, mollusk shells) and in vitro model systems, so studying the materials in their functional form.

Tuning properties of functional surfaces as potent and selective binders:
Recognition and binding of biomolecules or pollutant organics by functionalized surfaces is a process of high importance in diverse areas such as biocompatibility, catalysis (heterogeneous), sensing, waste removal, electrochemistry and to nanoelectronics. We aim at the elucidation of the Atomic/Molecular level of the surfaces, and the structure, chemistry and dynamics of biomolecules and organics when bound by the synthetic surfaces. Identifying the molecular details that enable binding specificity and strength are implemented as the basis for rational design of desired functionalities. Surfaces which exhibit a wide diversity of chemical characteristics are explored; these span mesoporous (high surface area materials) silica and mesoporous carbon.

Post doc: Wolfson Postdoctoral Fellow, Washington University at St. Louis, 1989-1993

Ph.D: Weizmann Institute of Science, 1989

A. Akiva-Tal, S. Kababya, Y.S. Balazs, L. Glazer, A. Berman, A. Sagi, and A. Schmidt. In situ molecular NMR picture of bioavailable calcium stabilized as amorphous CaCO3 biomineral in crayfish gastroliths. Proc. Natl. Acad. Sci. USA, 108 14763–14768, 2011.

N. Yaacobi-Gross, M. Soreni-Harari, M. Zimin, S. Kababya, A. Schmidt and N. Tessler. Molecular control of quantum-dot internal electric field and its application to CdSe-based solar cells. Nature Materials 10:974-979, 2011.

I. Ben-Shir, S. Kababya, I. Katz, B. Pokroy and A. Schmidt. Exposed and Buried Biomineral Interfaces in the Aragonitic Shell of Perna Canaliculus Revealed by Solid State NMR.
Chemistry of Materials, 25:4595−4602, 2013

I. Ben-Shir, S. Kababya, and A. Schmidt. The molecular details of amorphous silica surfaces determine its binding specificity to small amino acids. J. Phys. Chem. C, 118: 7901−7909, 2014.

S. Kababya, A. Gal, K. Kahil, S. Weiner, L. Addadi and A. Schmidt. Phosphate-Water Interplay tunes amorphous calcium carbonate metastability: Spontaneous phase separation and crystallization vs. stabilization viewed by Solid State NMR. J. Am. Chem. Soc., 137, 990-998, 2015.

J. Sundaresan, S. Kababya, A. Schmidt and S. Vega. Deuterium MAS NMR and local molecular dynamic model to study adsorption-desorption kinetics of a dipeptide at the inner surfaces of SBA-15. J. Phys. Chem. C, 120, 2797−2806, 2016.

Name Email Room Phone
Dr. Lra Ben Shir 228 3748/2140
Efrat Pri-Gal 225 2679