Lingtao Wang,Ruiting Xu,Lingjie Meng,Qiuyang Zhang,Zheng Qian,Jie Chen,Changjiang Pan
Although magnesium alloy has received tremendous attention in biodegradable cardiovascular stents , the poor in vivo corrosion resistance and limited endothelialization are still the bottlenecks for its application in cardiovascular stents. Fabrication of the multifunctional bioactive coating with excellent anti-corrosion on the surface is beneficial for rapid re-endothelialization and the normal physiological function recovery of blood vessels. In the present study, a bioactive hydrogel coating was established on the surface of magnesium alloy by copolymerization of sulfobetaine methacrylate (SBMA) and acrylamide (AM) via ultraviolet (UV) polymerization, followed by the immobilization of fucoidan (Fu). The results showed that the as-prepared multifunctional hydrogel coating could enhance the corrosion resistance and the surface wettability of the magnesium alloy surface, endowing it with the ability of selective albumin adsorption; meanwhile, it could augment biocompatibility. The following introduction of fucoidan on the surface could further improve the hemocompatibility characterized by reducing protein adsorption , minimizing hemolysis, and preventing platelet aggregation and activation. Additionally, the immobilized fucoidan promoted endothelial cell (EC) growth, as well as up-regulated the expression of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in endothelial cells (ECs). Consequently, this research paves a novel approach to developing a versatile bioactive coating for magnesium alloy surfaces and lays a foundation in cardiovascular biomaterials .
Bilayer-type hydrogel composites that respond to multiple stimuli provide a useful approach for manufacturing soft actuators and intelligent sensors. In this study, we propose two types of bilayer hydrogel composites (referred to as “N” type and “D” type). The “N” type and the “D” type separately consist of poly(N-isopropylacrylamide) (PNIPAM) and poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) bilayer hydrogels, with acrylamide (AM) as the co-monomer. The “N” type hydrogel composite exhibits oriented bending as temperature increases or as environmental salt concentration increases. The “D” type also presents oriented bending as temperature increases. Additionally, it demonstrates bending and changes color based on the pH of the surrounding solution, since it is doped with an acid-based pH-indicator. In a demonstration, we present several straight rods composed of a mixture of “N” and “D” type hydrogel composites that are able to morph into the letters “SOS” under environmental changes (temperature or pH). This can be used as a visual environmental indicator, or as an alarm. Furthermore, we show structures composed of a mixture of “N” and “D” composites imitating the flexible motions of a ballet dancer or a Tai Chi master. These mixed bilayer polymer composites may be used for applications in soft robotics, biomimetic devices, and environmental sensors.
In this paper, a kind of superabsorbent resin (SAR) with superior quality for hygiene products was developed using Fructus Aurantii Immaturus pectin (FAIP) from Citrus aurantium L.. FAIP-g-AM/AMPS SAR was established by free radical graft co -polymerization with FAIP as skeleton structure, N, N′-Methylene-bis (acrylamide) (MBA) as the cross-linker. Meanwhile, the functional monomers of acrylamide (AM) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) were introduced. The structure and morphology of FAIP-g-AM/AMPS were characterized by FTIR , 13 C NMR, XRD, SEM and TG-DSC analysis. The results confirmed that the AFIP-g-AM/AMPS SAR was successfully prepared, which exhibited a three-dimensional (3D) network structure and an excellent thermal stability . The absorption and retention capacity of FAIP-g-AM/AMPS was comparable to or even better than commercial diapers and sanitary napkins. Significantly, FAIP-g-AM/AMPS itself exhibited excellent antibacterial and safety. FAIP-g-AM/AMPS has an inhibition ratio of 97.1 % for Escherichia coli ( E. coli ) and 98.5 % for Staphylococcus aureus ( S. aureus ), and was non-irritating and non-allergic to the skin. In addition, FAIP-g-AM/AMPS presented amazing biodegradability and a weight loss reached 37.1 % after 30 days by soil burial test. The research provides a safe and high-performance SAR, which expected to be used in hygiene products such as baby diapers, adult incontinence pads and sanitary napkins.
危险品化学品经营许可证（带存储）