Re-assessing viologens for modern bio-electrocatalysis.

Viologens, 1,1'-disubstituted-4,4'-bipyridinium salts, are organic redox species that can be used in place of NADPH as mediators for redox enzymes. In this study, using the reduction of oxidized glutathione by glutathione reductase as a model system, a rationally designed library of viologens covering a range of polarities and functional groups were explored as electron transfer mediators for bio-electrocatalysis. Through a series of electrochemical investigations, the reduction potential was found to be the primary determining factor for electron transfer between the viologen and enzyme.

Linear and Nonlinear Optical Properties of All- and All- Poly(-phenylenevinylene).

Poly(-phenylenevinylene) (PPV) is a staple of the family of conjugated polymers with desirable optoelectronic properties for applications including light-emitting diodes (LEDs) and photovoltaic devices. Although the significant impact of olefin geometry on the steady-state optical properties of PPVs has been extensively studied, PPVs with precise stereochemistry have yet to be investigated using nonlinear optical spectroscopy for quantum sensing, as well as light harvesting for biological applications. Herein, we report our investigation of the influence of olefin stereochemistry on both linear and nonlinear optical properties through the synthesis of all- and all- PPV copolymers.

Biocatalytic reductive amination as a route to isotopically labelled amino acids suitable for analysis of large proteins by NMR.

We demonstrate an atom-efficient and easy to use H-driven biocatalytic platform for the enantioselective incorporation of H-atoms into amino acids. By combining the biocatalytic deuteration catalyst with amino acid dehydrogenase enzymes capable of reductive amination, we synthesised a library of multiply isotopically labelled amino acids from low-cost isotopic precursors, such as HO and NH. The chosen approach avoids the use of pre-labeled H-reducing agents, and therefore vastly simplifies product cleanup.

-Selective Acyclic Diene Metathesis Polymerization of ,-Dienes.

The / stereochemistry of repeating alkenes in polymers provides a powerful handle to modulate the thermal and mechanical properties of these soft materials, but synthetic methods to precisely dictate this parameter remain scarce. We report herein a -selective acyclic diene metathesis (ADMET) polymerization of readily available α,ω-diene monomers with high functional group tolerance. Identification of a highly stereoselective cyclometalated Ru catalyst allowed the synthesis of a broad array of polymers with contents up to 99%.

A hydrogen-driven biocatalytic approach to recycling synthetic analogues of NAD(P)H.

We demonstrate a recycling system for synthetic nicotinamide cofactor analogues using a soluble hydrogenase with turnover number of >1000 for reduction of the cofactor analogues by H. Coupling this system to an ene reductase, we show quantitative conversion of -ethylmaleimide to -ethylsuccinimide. The biocatalyst system retained >50% activity after 7 h.

In-home vascular testing program during the COVID-19 pandemic.

This is a retrospective review of a pilot program to provide in home vascular testing to patients during the COVID-19 Pandemic. Results: Eighty-four patients underwent a total of 105 vascular imaging tests as part of the program. Two patients required hospitalization secondary to imaging findings.