Anal Chim Acta
January 2015
Chiral recognition is the fundamental property of many biological molecules and is a quite important field in pharmaceutical analysis because of the pharmacologically different activities of enantiomers in living systems. Enantio-differentiating signal of the sensor requires specific interaction between the chiral compounds (one or a mixture of enantiomers) in question and the selector. This type of interaction is controlled normally by at least three binding centers, whose mutual arrangement and interacting characteristics with one of the enantiomers effectively control the selectivity of recognition.
View Article and Find Full Text PDFA simple hyphenation approach was adopted to obtain a new molecularly imprinted micro solid-phase extraction fiber (as a selective extraction tool) and complementary molecularly imprinted polymer coated pencil graphite electrode (as a detection tool) for the selective and sensitive analysis of epinephrine, which is a disease biomarker prevalent at ultra trace level in biological fluids. In both extraction and detection processes, the functionalized multiwalled carbon nanotubes (CNT-mers) were preferred to multiwalled carbon nanotubes (unmodified) in order to obtain a stable homogeneously dispersed imprinted polymer matrix of better electroconductivity and adsorptive characteristics. The hyphenation of both tools helped dual pre-concentration of epinephrine so as to achieve the stringent limit [limit of detection: 0.
View Article and Find Full Text PDFA novel molecularly imprinted polymer, selective for human hemoglobin, was immobilized on the surface of CdS quantum dots-multiwalled carbon nanotubes nanoconjugate-modified pencil graphite electrode. The fabricated sensor was found to be water-compatible and biologically benign, since the molecular imprinting was exclusively carried out in water, without any protein denaturation and electrode fouling. Notably, the pencil graphite electrode modified with merely a nanoconjugate matrix might involve the onset possibilities of electrode passivation and protein denaturation.
View Article and Find Full Text PDFCarbon-nanotubes play a pivotal role in molecularly imprinted polymer technology for inculcating conducting property, high surface to volume ratio, and maximum porosity in the film texture. Contrary to the non-covalent heterogeneous dispersion of pure (unmodified) multiwalled carbon nanotubes in the imprinted polymer film, the homogeneous distribution of their functionalized derivative was found more effective to augment the sensitivity of the measurement. This could be made feasible using multiwalled carbon nanotubes bearing terminal monomeric unit (termed as "CNT-mer") for the polymerization (one CNT-mer in each repeating unit).
View Article and Find Full Text PDFThis study describes the synthesis of a new class of substrate-selective molecularly imprinted polymer. This involved tetraethylene glycol 3-morpholin propionate acrylate (functional monomer) and bovine serum albumin (template) for polymerization in aqueous condition, using "surface grafting-from" approach directly on a vinyl exposed multiwalled carbon nanotubes-ceramic electrode. The analyte recapture at pH 6.
View Article and Find Full Text PDFWe review the fabrication processes and properties of waveguides that have been made from chalcogenide glasses including highly nonlinear waveguides developed for all-optical processing.
View Article and Find Full Text PDFWe present a systematic study of Ge(x)As(y)Se(1-x-y) bulk chalcogenide glasses to determine the best composition for fabricating all-optical devices. The dependence of physical parameters such as the band-gap, glass transition temperature and third order optical nonlinearity (n(2)) on composition has been studied and a relation between the bond-structure and elevated linear loss levels in high Germanium glasses has been identified. It is found that glasses with 11