Biocatalysis is playing an increasingly important role for chemical, pharmaceutical, and food industries, owing to its high efficiency, selectivity and environment-friendliness. However, it remains challenging to improve the catalytic activity of enzymes since the most frequently used strategies are costly and time-consuming. In the current study, a new type of glycogen-based dynamic nano-frameworks is prepared as additives for the direct activation of carbonic anhydrase ( bovine erythrocytes [bCA]). The boronic acid functionalization of the branched glycogen structures can provide N B coordination with bCA, leading to the conjugation and stabilization of the target enzyme. As a result, the glycogen with a 10% substitution degree ( Gly-PBA 10 ) showed a higher activation effect for bCA than that of glycogen with a 20% substitution degree ( Gly-PBA 20 ). Furthermore, the mechanism for interactions between the dynamic frameworks and bCA has been studied through combined techniques of dynamic light scattering, circular dichroism spectroscopy, and isothermal titration calorimetry. The results suggested different protein binding modes and stabilization abilities for the protein secondary structures from these two types of functionalized dynamic frameworks. This study provided new insights into the protein-polymer interactions that can be beneficial for various biochemical applications. Graphical
Recently, vitrimers with a reversible N → B coordination dynamic structure have garnered interest not only for their self-healing and reprocessable properties but also for their hydrolytic stability. Reported vitrimers with N → B internal coordination dynamic structure were excessively rigid, limiting their stretchability and toughness. This study synthesized a cross-linking agent (DNCB) with a cyclic nitrogen-boron coordination structure. This agent was then used in copolymerization with n-butyl acrylate (BA) and 4-vinylphenylboronic acid (BOH) to create soft vitrimers. By systematically tuning the composition, soft vitrimers exhibit water resistance along with high viscoelasticity, stretchability, toughness, and adhesive properties against various substrates. The observed mechanical behavior is attributed to the rapid relaxation of N → B coordination bonds and slow relaxation of B-O bonds in boroxine within the polymer network. It is anticipated that these soft vitrimers will be applied in adhesives, flexible electronics, and soft robotics due to their favorable properties.
危险品化学品经营许可证（带存储）