Chronic kidney disease caused by functional impairment of glomerular endothelial cells (GECs) is one of the etiologies of hemodialysis treatment. As a critical component of the hemodialysis process, hemodialysis membranes having been suffering from intricated modification methods. In order to solve a series of problems caused by blood incompatibility, usually triggered by rough surfaces, an anticoagulant coating with a similar physical structure and physiological properties to GECs was prepared on the polyethersulfone (PES) membrane. The smooth glomerular endothelium-like coating was obtained by a hydrated layer formed by tannic acid (TA) and α-lipoic acid (α-LA). We explored two possible reaction mechanisms of TA and α-LA, which were characterized and discussed by ATR-FTIR and XPS. Besides, the hydrophilic and negatively charged coating has filtration and anticoagulant properties similar to those of GECs. The results show that the modified membranes have appreciable hydrophilicity (the water contact angle is 29.7°) as well as high urea removal rate (96.5%) and BSA protein retention (99.7%). In addition, the modified membranes show favorable hemocompatibility and free radical scavenging ability. The reduction of platelet adhesion number is reduced by 98.7% and PRT is prolonged to 297 s. DPPH and ABTS radical scavenging capacity reach 1.18 and 0.89 μmol/cm 2 , respectively. In this work, a surface coating mimicking GECs was fabricated for the potential candidates of new hemodialysis membranes, which will significantly enhance the dialysis efficiency and alleviate the coagulation.
Nina Bao,Di Wang,Xizhe Fu,Hujun Xie,Guizhen Gao,Zisheng Luo
LotusReceptaculum Nelumbinishas been sparking wide research interests due to its rich phenolic compounds. In the present work, ultrasonic-assisted extraction coupled with glycerol was employed to extract phenolic compounds fromReceptaculum Nelumbinisand the process was optimized using a response surface methodology with Box-Behnken design (BBD). The optimal conditions for the total phenolic content (TPC) extract were obtained: glycerol concentration of 40%, an extraction temperature of 66 °C, ultrasonic time of 44 min, and the solvent-to-solid ratio of 55 mL/g. Under these optimum extraction conditions, the extraction yield of TPC was 92.84 ± 2.13 mg gallic acid equivalents (GAE) /g. Besides, the antioxidant activities demonstrated the ability of free radical scavenging by four different methods that included 2,2-Diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and reducing activity (RA) were 459.73 ± 7.07, 529.97 ± 7.30, 907.61 ± 20.28, and 983.66 ± 11.80 μmol TE/g, respectively. Six phenolic compounds were identified by ultra-high pressure liquid chromatography combined with triple-time-of-flight mass spectrophotometry (UPLC-Triple-TOF/MS) from the extracts. Meanwhile, Fourier transform infrared (FTIR) was conducted to identify the characteristic functional groups of the extracts and thus reflected the presence of polyphenols and flavonoids. Scanning electron microscopy (SEM) illustrated the microstructure difference of four treatments, which might explain the relationships between antioxidant activities and the structures of phenolic compounds.
危险品化学品经营许可证（带存储）