title: Enatioselective quantitative separation of D- and L-thyroxine by molecularly imprinted micro-solid phase extraction silver fiber coupled with complementary molecularly imprinted polymer-sensor.
abstract: Thyroxine is a known disease biomarker which demands a highly sensitive and selective technique to measure ultratrace level with enantiodifferentiation of its optical isomers (d- and l-), in real samples. In this work, an approach of hyphenation between molecularly imprinted micro-solid phase extraction and a complementary molecularly imprinted polymer-sensor was adopted for enantioseparation, preconcentration, and analysis of d- and l-thyroxine. In both techniques, the same imprinted polymer, coated on a vinyl functionalized self-assembled monolayer modified silver wire, was used as the respective extraction fiber as well as sensor material. This combination enabled enhanced preconcentration of test analyte substantially so as to achieve the stringent limit [limit of detection: 0.0084 ng mL(-1), RSD=0.81%, S/N=3 (d-thyroxine); 0.0087 ng mL(-1), RSD=0.63%, S/N=3 (l-thyroxine)] of clinical detection of thyroid-related diseases, without any problems of non-specific false-positive contribution and cross-reactivity.
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: Mahavir Prasad
authors.initials: MP
authors.lastname: Tiwari
authors.forename: Rashmi
authors.initials: R
authors.lastname: Madhuri
authors.forename: Piyush Sindhu
authors.initials: PS
authors.lastname: Sharma
mesh_terms: D054802:Molecular Imprinting / Q000295:instrumentation / Q000379:methods*; D011108:Polymers / Q000737:chemistry; D052616:Solid Phase Extraction / Q000295:instrumentation / Q000379:methods*; D013237:Stereoisomerism; D013974:Thyroxine / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D011108:Polymers; D013974:Thyroxine