Highly selective and sensitive analysis of γ-aminobutyric acid using a new molecularly imprinted polymer modified at the surface of abrasively immobilized multi-walled carbon nanotubes on pencil graphite electrode

This work describes the development of an electrochemical sensor based on a new molecularly imprinted polymer for the detection of gamma-amino butyric acid at ultra-trace level. This is comprised of a thin imprinted film exploiting an abrasive immobilization of functionalized multi-walled carbon nanotubes on the tip of a pencil graphite electrode. For the reason that gamma-aminobutyric acid is an electro-inactive species, its o-pthalaldehyde/sulphite derivative was used as a template for imprinting polymer made from a typical functional monomer (5-fluorouracil-N-acetylacrylamide) and cross-linking agent (ethylene glycol dimethacrylate) in the porogen, dimethyl sulphoxide. The electrodics of the template was explored using various techniques, viz., cyclic voltammetry, differential pulse anodic stripping voltammetry, and chronocoulometry. The template detection, in terms of gamma-aminobutyric acid, at stringent limits of clinical settings was feasible by differential pulse anodic stripping voltammetry technique in the linear concentration range, 0.75-205.19 ng mL(-1) (correlation coefficients 0.999, detection limits 0.28 ng mL(-1)), without any cross-reactivity and false positives in aqueous, human serum, and cerebrospinal fluid. (C) 2013 Elsevier Ltd. All rights reserved.