Boronic acid-based sensors for saccharides have been developed via biocatalysis. The self-doped copolymer of poly(aniline-co-3-aminobenzeneboronic acid) [poly(aniline-co-AB)], with various mole ratios of two components, was synthesized by oxidative enzymatic polymerization using a natural biocatalyst such as horseradish peroxidase together with an anionic polyelectrolyte template (sulfonated polystyrene) under mild conditions (pH 4.5). Poly(aniline-co-AB), having an aniline boronic acid-to-aniline ratio of 1:2 on average, gave rise to a green doped polymer with absorption maxima at 745 nm. The potentiometric detection of saccharides using poly(aniline-co-AB) is presented. Characteristics of both transient and steady-state response associated with the complex formation of poly(aniline-co-AB) with various saccharides were monitored by UV-vis spectroscopy and cyclic voltammetry (CV). The results obtained from UV-vis spectroscopy and CV show that the sensitivity of enzymatically synthesized water-soluble poly(aniline-co-AB) for various saccharides was improved significantly compared to the chemically synthesized counterpart. A possible mechanism for the sensitive detection of sugar molecules by boronic acid is proposed on the basis of UV-vis and IR spectrophotometry, and four-point probe conductivity measurements.

2020) Development of silver nanoparticle-based hydrogel composites for antimicrobial activity, Green Chemistry Letters and Reviews, 13:1, 34-40, ABSTRACT Antimicrobial function of Ag nanoparticles (NPs) has a strong correlation with the released Ag + cations that are produced by oxidation of Ag NPs in a solution state under ambient condition. Therefore, in order to develop anti-infective materials for biomedical applications, one needs to include Ag NPs inside biocompatible materials, which can allow slow release of Ag + cations. Hydrogels of natural polymers could be an ideal choice for the purpose because (a) the physicochemical properties of hydrogels resemble with biological tissue, and (b) the inclusion of Ag NPs inside hydrogels prevents the direct release of Ag NPs, while allowing the release of Ag + cations out of the hydrogels. In this regard, we present a simple strategy for producing Ag NPscontaining hydrogel based on natural alginate polymers. The chemical modification of alginate, blending with Ag NPs, gelation by photo-crosslinking process have been discussed in connection with antimicrobial reaction on model bacterium.

Three structurally different aniline monomers, which can not be polymerized by chemical methods, have been polymerized with horseradish peroxidase. Enzymatic synthesis of linear polyaniline requires template molecules to minimize branching in the polyaniline backbone. Monomers having methoxy and methyl blocking groups at the ortho or meta position could induce the conducting form of para-linked polyaniline without the use of an anionic template, such as SPS. A new mild peroxide, peroxyacetic acid, was identified and used to oxidize horseradish peroxidase in water.

No abstract

No abstract

Cu(In,Ga)(Se,S)2 modules with a frameless glass to glass structure were fabricated by replacing the currently used EVA with new encapsulants, and their characteristics including optical, mechanical, and reliability properties were investigated.

Solid polymer electrolytes based on poly(ethylene glycol)-polyurethane (PEG-PU) complexed with LiClO 4 salt have been prepared by the solvent casting method. A PEG-PU material (PEG:4,4'-diphenylmethane diisocyanate:1,4-butanediol = 1:2:1) was synthesized through a typical two-step condensation reaction. We investigated the effects of the salt concentration on the ionic conductivity (σ) and the glass transition temperature (T g ) of the complex electrolytes by using alternating current impedance spectroscopy, differential scanning calorimetry, and dynamic mechanical thermal analysis. The measured values of both σ and T g exhibited similar tendencies in that they had maxima within the range studied, probably because of two opposite effects, i.e., the increased number of carrier ions and the decreased chain mobility (or increased T g ) caused by the increase in the salt concentration. The highest conductivity, on the order of 2.43 ×10 6 Scm -1 , was obtained at an [O]/[Li + ] ratio of ca. 16 (0.92 mol salt per kg of matrix polymer).

No abstract