Complete Glucose Electrooxidation Enabled by Coordinatively Unsaturated Copper Sites in Metal-Organic Frameworks.

The electrocatalytic oxidation of glucose plays a vital role in biomass conversion, renewable energy, and biosensors, but significant challenges remain to achieve high selectivity and high activity simultaneously. In this study, we present a novel approach for achieving complete glucose electrooxidation utilizing Cu-based metal-hydroxide-organic framework (Cu-MHOF) featuring coordinatively unsaturated Cu active sites. In contrast to traditional Cu(OH)2 catalysts, the Cu-MHOF exhibits a remarkable 40-fold increase in electrocatalytic activity for glucose oxidation, enabling exclusive oxidation of glucose into formate and carbonate as the final products. The critical role of open metal sites in enhancing the adsorption affinity of glucose and key intermediates was confirmed by control experiments and density functional theory simulations. Subsequently, a miniaturized nonenzymatic glucose sensor was developed showing superior performance with a high sensitivity of 214.7 µA mM-1 cm-2 , a wide detection range from 0.1 µM to 22 mM, and a low detection limit of 0.086 µM. Our work provides a novel molecule-level strategy for designing catalytically active sites and could inspire the development of novel metal-organic framework for next-generation electrochemical devices.

[Application of crotch-shaped vein grafts in repairing defects of the vessels with a large diameter].

OBJECTIVE: To investigate the results and application value of crotch-shaped vein grafts in repairing. METHODS: From June 1998 to October 2003, 35 cases of vessel defects with defects of the vessels with a large diameter were repaired with crotch-shaped vein graft (29 males and 6 females, aged 18 to 45 years with an average of 25.7 years). The locations of defects were femoral artery in 25 cases, popliteal artery in 2 cases, femoral vein in 7 cases, and subclavian vein in 1 case. The interval between injury and operation was 1-8.5 hours (4.1 hours on average). The blood flows of trouble and healthy vascular were determined with Doppler detector and compared preoperatively and postoperatively. RESULTS: All the anastomotic stomas were patent in 35 cases. Thirty-one cases were followed up 6 weeks to 24 months (9.5 months on average), the patent rate was 100%, no case occurred vasospasm or thromboembolism; 2 cases occurred stomal leak and became hematoma, 3 cases occurred muscular necrosis, and the 5 cases achieved primary healing after secondary operation. The Doppler results showed that there was statistically significant difference in the blood flow between postoperation and pre-operation (P < 0.01), but no statistically significant difference when compared the trouble vascular after operation with healthy vascular (P > 0.05). CONCLUSION: The method of crotch-shaped vein grafts is safe and effective in repairing defects of vessels with a large diameter, which is easy to draw materials and handy to operate. It has a promising value in clinical application.