Membrane-based biomedical processes have increased considerably in recent years. However, the natural disadvantages of common membrane materials, such as hydrophobic surface and poor biocompatibility, cause many side effects in use and cumber further applications. In this work, to meet the requirements of biomedical applications, a novel sugar-containing monomer (D-gluconamidoethyl methacrylate (GAMA)) was grafted on polypropylene microporous membrane (PPMM) with an UV-induced polymerization to improve both the surface hydrophilicity and hemocompatibility. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy were employed to confirm the surface modification on the membranes. Water contact angle, protein adsorption, and platelet adhesion measurements were used to evaluate the anti-fouling property and the hemocompatibility of the membranes. It was found that the GAMA grafting degree increases reasonably with the increase of GAMA monomer concentration, and then the increase slows down when the GAMA concentration exceeds 40 g/L. At the same time, a 20-25-min UV irradiation is enough for the grafting polymerization. The water contact angle of the modified membrane decreases from 149 to 64°with the increase of GAMA grafting degree from 0 to 6.18 wt %, which indicates a hydrophilic variation of the membrane surface by the grafting of GAMA. Furthermore, the modified membranes show higher water and protein solution fluxes, lower BSA adsorption, and better flux recovery after cleaning than those of the original PPMM. Platelet adhesion experiment also reveals that a more hemocompatible interface can be obtained between the membrane and the biomolecules.

Increasingly, carbohydrate-protein interactions are viewed as important mechanisms for many biological processes such as blood coagulation, immune response, viral infection, inflammation, embryogenesis, and cellular signal transfer. However, the weak affinity of the interactions and the structural complexity of carbohydrates have hindered efforts to develop a comprehensive understanding of carbohydrate functions. Fortunately, synthetic polyvalent glycoligands give us a chance to reveal the nature of these biological processes. In this work a sugar-containing monomer (alpha-D-allyl glucoside (AG)) was grafted onto polypropylene microporous membrane (PPMM) by UV-induced graft polymerization to generate a glycosylated porous surface for the first time. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy were employed to confirm the glycosylation. Water contact angle measurement was used to evaluate the hydrophilicity change of the surfaces before and after the graft polymerization of AG. It was found that the grafting density increased reasonably with the increase of AG monomer concentration, and then this increase slowed when the AG concentration exceeded 80 g/L. At the same time a 20-25 min UV irradiation was enough for the grafting polymerization. The photoinitiator concentration also influenced the grafting density obviously, and there was an optimal concentration of the photoinitiator for the grafting process. The water contact angle of the polyAG-tethered membrane surface decreased from 149 degrees to 80 degrees with the increase of grafting density from 0 to 187.76 microg/cm2, which indicated a hydrophilic variation of the membrane surface by the grafting of AG. Results also indicated that the surface-grafted polyAG chains showed weak interaction with Con A when the grafting density was low. However, when the sugar density exceeded 90 microg/cm2, the binding affinity increased dramatically which was the due to the "glycoside cluster effect".

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With the vigorous development of hydrogels, hydrogel adhesion has attracted increasing attention in the last decade, but strong adhesion remains a challenge due to plenty of water in hydrogels. The...

A versatile approach based on click chemistry to synthesize polyphosphazene glycopolymers is presented. The glucose‐substituted polyphosphazene was synthesized by nucleophilic substitution of poly(dichlorophosphazene) with propargylamine and the subsequent azide/alkyne “click” reaction of poly[di(propargylamine)phosphazene] (PDPAP) with azidosugar. The relative proportion of the glucose substituent can be easily controlled over a broad range by varying the amount of azidoglucose used in the azide/alkyne “click” reaction. magnified image

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In this work, molecular dynamics (MD) simulation was employed to evaluate the influence of hydrophilization on the interaction of polypropylene surfaces with water. Constrained MD and simulated annealing were applied to construct theoretical models for the amorphous surfaces of hydrophobic polypropylene and those hydrophilized with amino, carboxyl, ammonium, and carboxylate groups. These model surfaces were studied by wetting with water droplets, and the corresponding water contact angles were calculated and compared with experimental results. We have confirmed the feasibility of the models in simulating the surfaces of realistic polypropylene. The structure and behavior of interfacial water molecules on these model surfaces can be achieved and compared with each other. Results indicate the formation of a dynamic hydration layer on the hydrophilized polypropylene surfaces. By the decomposition of the interaction potential, we found that the introduction of polar groups significantly improves the electrostatic component of the interaction potential for the surfaces with water.