A facile and versatile approach for the preparation of antifouling and antimicrobial polymer membranes has been developed on the basis of bioinspired polydopamine (PDA) in this work. It is well-known that a tightly adherent PDA layer can be generated over a wide range of material surfaces through a simple dip-coating process in dopamine aqueous solution. The resulting PDA coating is prone to be further surface-tailored and functionalized via secondary treatments because of its robust reactivity. Herein, a typical hydrophobic polypropylene (PP) porous membrane was first coated with a PDA layer and then further modified by poly(N-vinyl pyrrolidone) (PVP) via multiple hydrogen-bonding interactions between PVP and PDA. Data of water contact angle measurements showed that hydrophilicity and wettability of the membranes were significantly improved after introducing PDA and PVP layers. Both permeation fluxes and antifouling properties of the modified membranes were enhanced as evaluated in oil/water emulsion fil...

Antifouling and Antimicrobial Polymer Membranes Based on Bioinspired Polydopamine and Strong Hydrogen-Bonded Poly(N-vinyl pyrrolidone)

Devices that function in contact with blood are ubiquitous in clinical medicine and biotechnology. These devices include vascular grafts, coronary stents, heart valves, catheters, hemodialysers, heart-lung bypass systems and many others. Blood contact generally leads to thrombosis (among other adverse outcomes), and no material has yet been developed which remains thrombus-free indefinitely and in all situations: extracorporeally, in the venous circulation and in the arterial circulation. In this article knowledge on blood–material interactions and “thromboresistant” materials is reviewed. Current approaches to the development of thromboresistant materials are discussed including surface passivation; incorporation and/or release of anticoagulants, antiplatelet agents and thrombolytic agents; and mimicry of the vascular endothelium.

Blood compatible materials: state of the art

Synthesis and characterization of biodegradable polyurethane films based on HDI with hydrolyzable crosslinked bonds and a homogeneous structure for biomedical applications.

Bilayered vascular grafts based on silk proteins

Plasma treated polyethylene terephthalate/polypropylene films assembled with chitosan and various preservatives for antimicrobial food packaging.

Surface biocompatible modification of polyurethane by entrapment of a macromolecular modifier.

A macromolecular biocompatible surface modifier for polyurethane (PU), namely, polyurethane-block-poly (chloromethyl styrene) (PU-b-PCMS) copolymer, was synthesized by coupling hydroxyl-terminated PCMS with diisocyanate-terminated PU and further quaternizing. The synthesized surface modifier was blended with PU and heparin was absorbed on PU surface by ion exchange. The modification effectively increased the hydrophilicity and water absorption of PU. To evaluate the hemocompatibility of the modified blend films, the extent of platelet adsorption, plasma recalcification time and hemolysis were measured. To determine if the blend films were toxic to mammalian cells, viability of the cells cultured on the blend films was assayed. All results indicated that the blood and cell compatibilities of the PU films were improved significantly after entrapment of a few quaternized PU-b-PCMS copolymers into PU and further heparinizing.

Surface biocompatible construction of polyurethane by heparinization

The purpose of this study was to prepare and evaluate kaempferol-loaded carbopol polymer (acrylic acid) hydrogel, investigate its antioxidant activity in vitro, and compare the effects on drug release under different pH conditions. Drug release studies were conducted in three different pH media (pH 3.4, 5.4, and 7.4). The kaempferol-loaded hydrogel was prepared by using carbopol 934 as the hydrogel matrix. The morphology and viscosity of the preparation were tested to understand the fluidity of the hydrogel. The antioxidant activity of the preparation was studied by scavenging hydrogen peroxide and 2,2-diphenyl-1-picrilhidrazil (DPPH) radicals in vitro and inhibiting the production of malondialdehyde in mouse tissues. The results showed that kaempferol and its preparations had high antioxidant activity. In vitro release studies showed that the drug release at pH 3.4, 5.4, and 7.4 was 27.32 ± 3.49%, 70.89 ± 8.91%, and 87.9 ± 10.13%, respectively. Kaempferol-loaded carbopol hydrogel displayed greater swelling and drug release at higher pH values (pH 7.4).

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In Vitro Evaluation of Kaempferol-Loaded Hydrogel as pH-Sensitive Drug Delivery Systems

Three kinds of degradable and blood-compatible polyurethane (PU) were synthesized by coupling hydroxyl-terminated poly(vinylpyrrolidone) (PVP) with diisocyanate-terminated PU. The chemical structure and molecular weight of the synthesized copolymer were systematically characterized by nuclear magnetic resonance spectrum (1HNMR), Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The hydrophilicity and water absorption of the synthesized PU was increased by introducing PVP segment. To evaluate the hemocompatibility and degradability of the modified PU films, the extent of platelet adsorption, plasma recalcification time, hemolysis and degradation were measured. All results indicated that the blood compatibility and degradability of the PU films were improved significantly after introduction PVP segment into PU.

Qin Zhang

Papers

Surface biocompatible modification of polyurethane by entrapment of a macromolecular modifier.

Surface biocompatible construction of polyurethane by heparinization

In Vitro Evaluation of Kaempferol-Loaded Hydrogel as pH-Sensitive Drug Delivery Systems

Synthesis of Biodegradable and Blood-Compatible Polyurethane Based on Poly(vinylpyrrolidone)