Biocompatibility of a polymer-coated membrane possessing a hydrophilic blood-contacting layer: Adsorption-related assessment

Abstract

Objective: Currently, the foreign surfaces of extracorporeal circulation devices are coated with an acrylate-based copolymer that creates a hydrophilic blood-contacting layer to enhance biocompatibility. Several reports of acrylate-based copolymer with respect to biocompatibility have been published; however, the adsorption of peptide compounds on acrylate-based copolymer–coated membranes still requires clarity. In this study, we aimed to understand the adsorption of several peptide compounds of various molecular weights, including albumin, lysozyme, and vancomycin, on acrylate-based copolymer–coated membranes using in vitro studies. Methods: Six experimental circuits consisting of acrylate-based copolymer–coated tubes and membranes, and six comprising acrylate-based copolymer–coated tubes and non-coated membranes were prepared for comparison. An experimental solution, composed of albumin, lysozyme, vancomycin, and saline, was continuously stirred in a reservoir, recirculated in each experimental circuit, and then filtered. Concentrations of albumin, lysozyme, and vancomycin were measured after 0, 15, 30, 45, 60, 90, and 120 min of recirculation. Similar experiments were performed in all the prepared circuits. Results: The ratio of measured values at each time point to those at 0 min was not significantly different between acrylate-based copolymer–coated and non-coated membranes for albumin and lysozyme, but differed significantly for vancomycin; the ratios were higher in acrylate-based copolymer–coated than in non-coated membranes. Conclusion: This study suggests that albumin is not adsorbed on either acrylate-based copolymer–coated or non-coated membranes, that lysozyme is not adsorbed on either membrane or is adsorbed at a similar rate on both membranes, and that vancomycin is less adsorbed on acrylate-based copolymer–coated membranes. Thus, acrylate-based copolymer coating could inhibit the adsorption of various peptide compounds.

Activity of anticoagulant proteins on the polymer-coated and heparin-coated membranes in an extracorporeal circulation circuit

“…These results might be explained by adsorption. We previously performed experiments to evaluate adsorption in ACP-coated membranes 17 and found that ACP coating could inhibit the adsorption of various peptide compounds. Based on the present results, the quantitation of each anticoagulant protein was preserved despite the activity of those not preserved, which could be caused by adsorption.…”

Desialylation of platelet surface glycans enhances platelet adhesion to adsorbent polymers for lipoprotein apheresis

“…The exposure of whole blood to large adsorbent surfaces in therapeutic apheresis requires adsorbent polymers of particularly high blood compatibility to avoid adverse reactions at the blood-adsorbent interface, 26 such as activation of immune cells or platelets. While device-related parameters including the chemical composition, charge, and morphology of adsorbent polymers and the choice of the anticoagulant can influence blood cell activation in the extracorporeal circuit, 18 , 27 , 28 – 30 host-related factors may play a role, as well.…”

“…Aliquots of 500 μl of the platelet suspension were incubated for 60 min at 37°C with 1, 2.5, 5, 10, and 20 mU neuraminidase from Clostridium perfringens (Roche, Mannheim, Germany) per 10 8 platelets, or were left untreated. Platelets treated with 5 mU of neuraminidase were additionally analyzed at different time points (30,60,90, and 120 min). The presence of terminal sialic acid or galactose residues was analyzed by flow cytometry as described below.…”

Biocompatible Biomimetic Polymer Structures With an Active Response for Implantology and Regenerative Medicine Part I: Basic Principles of the Active Implant’s Biocompatibility

“…Действительно, известен вклад гидрофильности / гидрофобности в обеспечение биосовместимости полимерных материалов [62,166], что связывается с явлениями поверхностной адсорбции (например, в совместимости полимерных мембранных покрытий с кровью [157]), смачиваемостью поверхности, определяющей возможность распластывания и распространения псевдоподий и филоподий клеток (выростов или отростков клеток) на ней [3,37], оптимальностью для иммобилизации антибактериальных средств [110], и т.д. Однако, подобные эмпирические представления, несмотря на их корректность, не обладают полнотой и предсказательной силой, так как интегральной теории, учитывающей все аспекты вклада поверхностных механизмов в биосовместимость, на данный момент не существует.…”