Plasma surface modification of fibroporous polycarbonate urethane membrane by polydimethyl siloxane: structural characterization, mechanical properties, and in vitro cytocompatibility evaluation.

This article reports the surface modification of electrospun polycarbonate urethane membrane with polydimethyl siloxane (PDMS) using plasma-induced grafting technique for biomedical applications. The nonwoven membranes were characterized for their structure, performance, and compatibility with cells. The surface modification was confirmed by means of attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and energy dispersive X-ray analysis (EDXA). ATR-FTIR and EDXA analyses displayed characteristic absorption peaks of PDMS for the membrane. The structure and morphology of the developed membranes were studied using scanning electron microscope and microcomputed tomography (µCT). Scanning electron microscopy and µCT revealed the fibrous morphology and percentage porosity of the membranes before and after plasma modification. Static mechanical tests showed that the tensile strength was greater than 8 MPa. Physical characterization of the membranes after immersion in hydrolytic and oxidative media supports their biostability. Cytotoxicity of the membrane was evaluated using L929 fibroblast cells, and the results indicated that the membrane is cytocompatible. Accordingly, these results highlight the potential of this fibrous membrane for biomedical applications.

Structural characterization, mechanical properties, and in vitro cytocompatibility evaluation of fibrous polycarbonate urethane membranes for biomedical applications.

This paper reports the electrospinning of a series of oxidatively stable polycarbonate urethanes (PCU) [carbothane (ECT), bionate (EBN), and chronoflex (ECF)] using N,N-dimethyl formamide and tetrahydrofuran as the mixed solvent. The nonwoven membranes were characterized for their structure, performance, and compatibility with cells. Scanning electron microscope was utilized to study the structural morphology and fiber diameter. Microcomputed tomography (micro-CT) was used to characterize the 3D architecture, pore size distribution, and percentage porosity. All the membranes displayed a porous architecture with average fiber diameter in the range of 1.5-2 µm. Static mechanical tests on the membranes revealed that the tensile strength was greater than 7 MPa and the dynamic mechanical tests showed that the average storage modulus (E(i) ) is 2 MPa at 37°C. PCU membranes were subjected to accelerated in vitro degradation for 90 days in 20% hydrogen peroxide/0.1M cobalt chloride solution. Mechanical characterization of the membranes postdegradation confirmed a 64% reduction in tensile strength for EBN at the end of 90 days where as ECF and ECT did not show any significant mechanical property deterioration in the oxidative medium. Cytotoxicity of the membranes was evaluated using L929 fibroblast cells and the results indicated that all the PCU membranes were cytocompatible and showed good adherence to L929 cells. Accordingly, these results highlight the potential of these fibrous PCU membranes for biomedical applications but further in vivo correlation studies are required for better understanding of the biodegradation and biological efficacy.