NADH Photosynthesis System with Affordable Electron Supply and Inhibited NADH Oxidation

Photosynthesis offers a green approach for the recycling of nicotinamide cofactors primarily NADH in bio-redox reactions. Herein, we report an NADH photosynthesis system where the oxidation of biomass derivatives is designed as an electron supply module (ESM) to afford electrons and superoxide dismutase/catalase (SOD/CAT) cascade catalysis is designed as a reactive oxygen species (ROS) elimination module (REM) to inhibit NADH degradation. Glucose as the electron donor guarantees the reaction sustainability accompanied with oxidative products of gluconic acid and formic acid. Meanwhile, enzyme cascades of SOD/CAT greatly eliminate ROS, leading to a ≈2.00-fold elevation of NADH yield (61.1 % vs. 30.7 %). The initial reaction rate and turnover frequency (TOF) increased by 2.50 times and 2.54 times, respectively, compared with those systems without REM. Our study establishes a novel and efficient platform for NADH photosynthesis coupled to biomass-to-chemical conversion.     

Smart Design of Sensor-Coated Surgical Sutures for Bacterial Infection Monitoring

Virtually, all implantable medical devices are susceptible to infection. As the main healthcare issue concerning implantable devices is the elevated risk of infection, different strategies based on the coating or functionalization of biomedical devices with antiseptic agents or antibiotics are proposed. In this work, an alternative approach is presented, which consists of the functionalization of implantable medical devices with sensors capable of detecting infection at very early stages through continuous monitoring of the bacteria metabolism. This approach, which is implemented in surgical sutures as a representative case of implantable devices susceptible to bacteria colonization, is expected to minimize the risk of worsening the patient's clinical condition. More specifically, non-absorbable polypropylene/polyethylene (PP/PE) surgical sutures are functionalized with conducting polymers using a combination of low-pressure oxygen plasma, chemical oxidative polymerization, and anodic polymerization, to detect metabolites coming from bacteria respiration. Functionalized suture yarns are used for real-time monitoring of bacteria growth, demonstrating the potential of this strategy to fight against infections.