Reference type: Journal
Authors: Prasad BB, Srivastava A, Pandey I, Tiwari MP
Article Title: Electrochemically grown imprinted polybenzidine nanofilm on multiwalled carbon nanotubes anchored pencil graphite fibers for enantioselective micro-solid phase extraction coupled with ultratrace sensing of d- and l-methionine.
Publication date: 2013
Journal: Journal of Chromatography B
Volume: 912
Page numbers: 65-74.
DOI: 10.1016/j.jchromb.2012.10.010
Alternative URL: http://www.sciencedirect.com/science/article/pii/S1570023212005922

Abstract: An alternative method is presented for the modification of pencil graphite fibers using surface imprinting technology. In this new approach, we have adopted surface initiated electropolymerization of benzidine monomer, with simultaneous imprinting of template (d- and l-methionine), on carboxylated multiwalled carbon nanotubes anchored pencil graphite fiber. This yielded a nanostructured ultrathin imprinted film (58.3 nm) uniformly coated all along the perimeter and length of pencil graphite fiber, for micro-solid phase extraction with substantial adsorption capability. The same film is coated over the exposed tip of the pencil graphite fiber to serve as a complementary molecularly imprinted polymer-sensor. Both extraction and sensing devices are not capable to measure the stringent limit (0.016 ng mL-1) of clinical detection of methylenetetrahydrofolate reductase (MTHFR) gene mutation caused by acute methionine depletion, when used alone. However, on combination of both techniques, a successful enantioselective analysis of d- and l-methionine with excellent analytical figures of merit [limit of quantitation range: 0.03 - 30.00 ng mL-1, limit of detection: 0.0098 ng mL-1 (RSD = 2.04, S/N = 3)] could be achieved without any problem of non-specific false-positive contribution and cross-reactivity, in real samples
Template and target information: methionine
Author keywords: electropolymerization, d- and l-methionine, Molecularly imprinted micro-solid phase extraction pencil graphite fiber, enantioseparation, Differential pulse cathodic stripping voltammetry