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• Fast and efficient microwave assisted synthesis of a degradable polythiophene-based co-polymer. • Azomethine linkers amongst bithiophene units yield a continuously conjugated, conductive and redox-active framework. • Polymer degradation is a function of the pKa of the acid used to catalyse the hydrolysis with degradation times varying from 1 h to 6 months. • The polymer presents with sufficiently high conductivity for in vivo biomedical applications. As part of ongoing efforts to develop electroactive polymers (EAPs) which are biodegradable/bioresorbable, we report on the microwave assisted synthesis and characterization of an electrically conducting and electroactive polymer that capitalises on p K a sensitivity to initiate the system's fracture and breakdown. The system, poly(bis((thiophen-2-yl) methylene) benzene-1,4-diamine), a poly(thiophene-azomethine) co-polymer (PAZO), incorporates hydrolytically sensitive azomethine linkers amongst bithiophene units resulting in one continuously conjugated and redox-active macromolecular framework. Rapid microwave assisted synthesis allowed for facile preparation of the polymer with significantly reduced reaction times when compared to traditional synthetic routes. Electrochemical analysis indicated quasi-reversible electrochemical behaviour with sufficiently high conductivity for in vivo biomedical applications. The polymer displays tunable degradation behaviour whereby the time duration required for polymeric breakdown is a function of the p K a of the acid used to catalyse the reaction resulting in controllable degradation times ranging from 1 h to 6 months. The development of conductive polymeric materials that are fully degradable over pre-defined time periods opens up a portal to the next generation of EAPs for in vivo biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical and photochemical properties of [Ru(bpy)2dcb]Cl2 monolayers and their subsequent use for the detection of amino acids, e.g., proline, is reported; dcb is 4,4′-dicarboxy-2,2′-bipyridine and bpy is 2,2′-bipyridine. The ability of such a complex to form stable monolayers enables its utilization for the detection of oxalate and several amino acids, producing significant ECL. The electrochemical response of the Ru2+/3+ couple is electrochemically reversible and the monolayers show excellent stability with the response decreasing by less than 8% after continuous scanning over 4h. The ECL and current responses increase linearly with increasing analyte concentration 0.2⩽[Proline]⩽1nM while for hydroxy-proline the dynamic range is from 1 to 10nM. The ECL signal was monitored at ∼644nm, representing the λ max for the [Ru(bpy)2dcb]Cl2 monolayers. This wavelength is shifted by approximately 28nm compared to the photoexcited λ max for the same system. This technique is simple, rapid, selective and sensitive, and shows potential for the high-throughput quantitation of amino acids if adapted with other techniques such as FIA or LC systems. [Copyright &y& Elsevier]

The cover picture shows the release of the luminescent rhenium coordination complex (yellow spheres) in solution. This release is triggered by electrochemical stimulus applied through the cable to the metallopolymer, which is represented by the splash of blue paint. The irreversibility of the electrochemical release is highlighted by holes in the graph paper. G. Valenti, F. Paolucci, R. J. Forster, and co‐workers outline the photophysical and electrochemical properties of a novel metallopolymer containing [Re(bpy)(CO)3]+ moieties coordinated to a poly(4‐vinylpyridine) polymer chain in their Full Paper on page 55 ff. Release of the metal complexes can be triggered by oxidation or reduction of the rhenium complex. [ABSTRACT FROM AUTHOR]