Photoelectron Spectroscopy of the Adsorption of Amino Acids on Surfaces: Glycine on Si(O₂)

Abstract

We have studied chemically adsorbed glycine on the hydrophilic surface of the oxidized surface of silicon. A stable adsorbate layer is formed, which consists of zwitterionic glycine molecules. Most importantly, these zwitterionic molecules have a tendency for orientation in a direction perpendicular to the substrate surface, with COO- groups away from the surface and the NH3+ groups toward the surface.

Polarization-Induced Atomic Reconfigurations of Glycine on a Metal Surface

“…[9] gives the simple Gauss's law represented as a sum of atomic charges as Eq. [7] implies, but result for a parallel plate capacitor. That is, in that case, may be directly obtained as an integral over the actual charge distribution if it is known (e.g., from quantum calculations).…”

“…The first term on the right of Eq. [7] represents the self-field of element i; the second term is due to the N For a single flat boundary in the absence of point charges it real point charges within the boundary. This term need not be is easy to show that Eq.…”

“…The last term in Eq. [7] represents the contribution to the normal component of the electric field at element i from all other A point charge experiences an electric field of 2ps tot in the elements k on the boundary, i x k. That is, vicinity of a charged plane, the real charge being significantly reduced by the self-polarization.…”

“…A neutral, nonionic (NE) form of glycine is A fundamental understanding of the biocompatibility of stable, the two forms differing essentially by the motion of proteins with artificial implant materials has motivated ex-a proton from the NH 3 group (ZW) to the nearby COO 0 perimental studies of amino acid adsorption on solid surfaces group (NE). The dipole moment of the ZW form is several (1)(2)(3)(4)(5)(6)(7). Initial protein adsorption and subsequent surface-times greater than that of the NE form which seriously afinduced denaturization or change in conformation may acti-fects its interaction with a polarizable interface.…”

Adsorption and coadsorption of water and glycine on TiO2

“…[19][20][21][22][23][24][25][26][27][28][29] A few studies have used adsorption layers formed in situ [30][31][32][33][34][35][36][37][38][39][40][41] but never with water as a coadsorbate. No information, to our knowledge, has been reported on the energetics or kinetics of glycine adsorption on TiO 2 .…”