title: Enantioselective recognition of D- and L-tryptophan by imprinted polymer-carbon composite fiber sensor.
abstract: Electrochemical sensors demonstrating enantioselectivity to tryptophan enantiomers, with high selectivity and sensitivity, were fabricated by the use of a monolithic fiber of molecularly imprinted polymer-carbon composite. The recognition mechanism and performance of these sensors were evaluated by differential pulse anodic stripping voltammetry. The sensor imprinted for l-tryptophan not only discriminated the target from its analogues and other amino acids but also responded specifically in racemic mixture in aqueous, biological, and pharmaceutical samples. The binding kinetics of L-tryptophan was also established with the help of anodic stripping cyclic voltammetry and chronocoulometry. The detection limit for L-tryptophan was as low as 0.24 ng mL(-1) (signal/noise=3) which is appropriate for biomarking diseases, caused by an acute tryptophan-depletion, in clinical setting.
authors.affiliation: Analytical Division, Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India. prof.bbpd@yahoo.com
authors.forename: Bhim Bali
authors.initials: BB
authors.lastname: Prasad
authors.forename: Rashmi
authors.initials: R
authors.lastname: Madhuri
authors.forename: Mahavir Prasad
authors.initials: MP
authors.lastname: Tiwari
authors.forename: Piyush Sindhu
authors.initials: PS
authors.lastname: Sharma
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004563:Electrochemistry; D004566:Electrodes; D008855:Microscopy, Electron, Scanning; D054802:Molecular Imprinting; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism; D013379:Substrate Specificity; D014364:Tryptophan / Q000032:analysis* / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D011108:Polymers; D014867:Water; D002244:Carbon; D014364:Tryptophan