title: Immobilization and characterization of gamma-aminobutyric acid on gold surface.
abstract: gamma-Aminobutyric acid (GABA) is one of two main inhibitory neurotransmitters in the central nervous system that plays an important role in neuronal function and dysfunction. Immobilization of GABA molecules on a rigid surface in an ordered fashion will provide an opportunity to understand some of the fundamental properties related to its structure and function. In this study, we report a novel strategy for immobilization of bioactive GABA on gold substrate. GABA was immobilized in three consecutive steps, namely gold substrate amination, dextran covalent attachment, and GABA immobilization. Surface chemistry was verified at each step using XPS and FTIR. Bioactivity of GABA immobilized on the gold surface was studied using atomic force microscopy to reveal antigen-antibody binding. Nonspecific protein adsorption on the bioactive surface was analyzed quantitatively using anti-GABA antibody and an enzyme linked nonspecific anti-immunoglobulin-G antibody in an ELISA assay. GABA functionalized surface has high affinity for anti-GABA, while showing significantly low affinity for nonspecific anti-IgG antibody. All these data support the presence of a bio-functional immobilized GABA on the gold surface. In conclusion, we report a novel technique for immobilizing bioactive GABA molecules in an orderly fashion on gold substrates.
authors.affiliation: Harrington Department of Bioengineering, Fulton School of Engineering, Arizona State University, Tempe, Arizona, USA.
authors.forename: Tingting
authors.initials: T
authors.lastname: Wang
authors.forename: Gholam
authors.initials: G
authors.lastname: Ehteshami
authors.forename: Stephen
authors.initials: S
authors.lastname: Massia
authors.forename: Jit
authors.initials: J
authors.lastname: Muthuswamy
mesh_terms: D020099:Coated Materials, Biocompatible; D006046:Gold; D017550:Spectroscopy, Fourier Transform Infrared; D005680:gamma-Aminobutyric Acid / Q000737:chemistry
chemical_list: D020099:Coated Materials, Biocompatible; D005680:gamma-Aminobutyric Acid; D006046:Gold