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The paper reports on a novel localized surface plasmon resonance (LSPR) substrate architecture for the immobilization and detection of histidine-tagged peptides. The LSPR interface consists of an ITO (indium tin oxide) substrate coated with gold nanostructures. The latter are obtained by thermal deposition of a thin (2 nm thick) gold film followed by post-annealing at 500 °C. The LSPR interface was coated with poly[3-(pyrrolyl)carboxylic acid] thin films using electrochemical means. The ability of the LSPR interfaces coated with poly[3-(pyrrolyl)carboxylic acid] to chelate copper ions was investigated. Once loaded with metal ions, the modified LSPR interface was able to bind specifically to histidine-tagged peptides. The binding process was followed using LSPR. [ABSTRACT FROM AUTHOR]

The paper reports on the fabrication of superhydrophobic boron-doped diamond nanograss surfaces. The boron-doped diamond nanograss array (BDD NG) was prepared simply by reactive ion etching (RIE) with oxygen plasma of highly boron-doped (the boron doping level is 8 × 1019B cm−3) polycrystalline diamond electrodes. Depending on the RIE conditions, substrates with different nanograss densities can be prepared. Chemical functionalization of the NG array surface with octadecyltrichlorosilane (OTS) or 1H,1H,2H,2H-perfluorodecyltrichlorosilane (PFTS) led to the formation of superhydrophobic surfaces. Under optimized conditions, BDD NG surfaces with contact angles as high as 160° and quasi null hysteresis (< 2°) can be reached. A water droplet deposited on the surface tends to roll off when the NG surface was tilted by a few degrees. Furthermore, the BDD NG array chemically modified with PFTS displays oleophobic properties. A contact angle of 94° was measured for hexadecane. The resulting surfaces were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis, and contact angle (CA) measurements. [ABSTRACT FROM AUTHOR]

Selective removal of hexavalent chromium ions from aqueous solutions using a chitosan/gold nanoparticles composite film was demonstrated. Localized surface plasmon resonance (LSPR) was used to measure the interface stability and detect the incorporation of chromium ions over time. The effects of pH, ethylenediaminetetraacetic acid (EDTA), and various foreign ions such as trivalent chromium, sodium, calcium, phosphate, sulfate and chloride on the adsorption of hexavalent chromium were investigated. [ABSTRACT FROM AUTHOR]

The use of Au/SiOxinterfaces for the investigation of DNA hybridization using electrochemical impedance spectroscopy (EIS) and surface plasmon resonance (SPR) simultaneously is demonstrated. Standard glass chemistry was used to link single-stranded DNA (ss-DNA) on aldehyde-terminated Au/SiOxinterfaces. The layer thickness and amount of grafted oligonucleotides (ODNs) were calculated from SPR on the basis of a multilayer system of glass/Ti/Au/SiOx/grafted molecule. Capacitance and resistance values of the modified interface before and after hybridization were calculated from EIS data using an equivalent circuit and allowed the affinity rate constant, KA= 4.07 × 105M−1, to be determined. The EIS results were comparable to those obtained by SPR hybridization kinetics recorded in parallel. [ABSTRACT FROM AUTHOR]

Homogeneous chitosan films of various thicknesses (10–65 nm) were deposited on thin gold films through spin coating. The resulting interfaces were characterized using surface plasmon resonance (SPR), AFM, profilometry and cyclic voltammetry. The strong chelating properties of chitosan films to Fe3+were investigated using cyclic voltammetry. Through SPR measurements, an affinity constant between chitosan and Fe3+of 9.49 × 105M−1was determined with a detection limit as low as 250 ppb. [ABSTRACT FROM AUTHOR]

This paper reports on the use of electrochemical surface plasmon resonance (E-SPR) for the detection of carbohydrate-binding proteins. The generation of an SPR sensor specific to lectins Arachis hypogaea(PNA) and Maackia amurensis(MAA) is based on the electrochemical polymerization of oligosaccharide derivatives functionalized by pyrrole groups. The resulting thin conducting polymer films were characterized using E-SPR and atomic force microscopy (AFM). The specific binding of PNA to polypyrrole-lactosyl and of MAA to polypyrrole-3′-sialyllactosyl films was investigated using SPR. The detection limit was 41 nM for PNA and 83 nM for MAA. Through Scatchard analysis and linear transformation of the SPR sensorgram data, association (kass) and dissociation rate constants (kdiss) could be determined. [ABSTRACT FROM AUTHOR]

The communication reports on the high performance of hydrogen-terminated silicon nanowires and silicon nanowires coated with metal (Ag, Cu) nanostructures for the photodegradation of rhodamine B under UV and visible light irradiation. [ABSTRACT FROM AUTHOR]

Irradiation of a patterned benzophenone-terminated boron-doped diamond (BDD) surface with UV light (λ = 350 nm) in the presence of a 15mer oligonucleotide resulted in the covalent linking of the DNA strand to the BDD interface. [ABSTRACT FROM AUTHOR]