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A covalent interaction-based molecularly imprinted polymer (MIP) material for 3-chloro-1,2-propanediol (3-MCPD), a post-testicular anti-fertility agent and possible carcinogen and mutagen in food products containing acid-hydrolyzed vegetable proteins, has been successfully fabricated using 4-vinylphenylboronic acid as the functional monomer. Rebinding assay revealed that the binding constant, KB, for the receptor sites and non-specific sites are 1.93±0.1×104 and 2.74±0.7×102 M−1, respectively. The estimated number of receptor site, Bmax, imprinted is 123.3±3 μmol/g of MIP. The MIP material is able to act as a potentiometric chemosensor for 3-MCPD via increase in Lewis acidity of the receptor sites upon reaction of the arylboronic acid with 3-MCPD to form the more acidic arylboronic acid esters. A simple pH glass electrode is sufficient to monitor the analyte-specific rebinding. In unbuffered aqueous media, linear potentiometric response from 0 to 350 ppm of 3-MCPD can be achieved. The MIP-based chemosensing in a soya sauce matrix has also been attempted. It is found that the dynamic range of the potentiometric chemosensing response of the MIP material is much reduced, probably due to the blocking or deactivation of receptor sites by interferents in soya sauces. Nevertheless, the present work demonstrated the feasibility of using MIP-based chemosensors as semi-quantitative analytical tools for screening purposes in quality control of food products. [Copyright &y& Elsevier]

A new ruthenium(II) photosensitizer, [RuII(py-pzH)3]2+ (where py-pzH=3-(2′-pyridyl)pyrazole), has been synthesized. The complex displayed outstanding excited state redox properties (estimated RuIII/RuII*≈−1.24 V vs. NHE) and was expected to sensitize the injection of electrons into the conduction band of anatase TiO2 upon visible irradiation. The photosensitizer was anchored onto the surface of anatase TiO2 particles via in situ silylation. The silyl-linkage displayed excellent stability in both aqueous media, over a wide pH range, and in common organic solvents. The resultant material, TiO2—[RuII(py-pz-Si≡)3], was found to be able to mediate degradation of CCl4 in neutral aqueous medium under broad band visible irradiation (λ>450 nm). The relation between the rate of degradation and concentration of substrate was explored and the mechanism of the photodegradation of the perhalogenated organic was discussed. [Copyright &y& Elsevier]

Reports the synthesis and characterization of a neutral trinuclear heterobimetallic cyano-bridged Ru(II)/Pt(II) complex, cisRu(phen)[sub 2][CN-Pt(DMSO)Cl[sub 2]][sub 2] (phen = 1,10-phenanthroline), as achemodosimetric ensemble for sulfhydryl-containing amino acids and peptides. Substrate binding process; Luminescent responses of complex 1 toward amino acids and peptides.