Study of the Structure of Hyperbranched Polyglycerol Coatings and Their Antibiofouling and Antithrombotic Applications

Moore, Eli and Robson, Alexander J. and Crisp, Amy R. and Cockshell, Michaelia P. and Burzava, Anouck L. S. and Ganesan, Raja and Robinson, Nirmal and Al‐Bataineh, Sameer and Nankivell, Victoria and Sandeman, Lauren and Tondl, Markus and Benveniste, Glen and Finnie, John W. and Psaltis, Peter J. and Martocq, Laurine and Quadrelli, Alessio and Jarvis, Samuel P. and Williams, Craig and Ramage, Gordon and Rehman, Ihtesham U. and Bursill, Christina A. and Simula, Tony and Voelcker, Nicolas H. and Griesser, Hans J. and Short, Robert D and Bonder, Claudine S. (2024) Study of the Structure of Hyperbranched Polyglycerol Coatings and Their Antibiofouling and Antithrombotic Applications. Advanced Healthcare Materials: e2401545. ISSN 2192-2659

Abstract

While blood‐contacting materials are widely deployed in medicine in vascular stents, catheters, and cannulas, devices fail in situ because of thrombosis and restenosis. Furthermore, microbial attachment and biofilm formation is not an uncommon problem for medical devices. Even incremental improvements in hemocompatible materials can provide significant benefits for patients in terms of safety and patency as well as substantial cost savings. Herein, a novel but simple strategy is described for coating a range of medical materials, that can be applied to objects of complex geometry, involving plasma‐grafting of an ultrathin hyperbranched polyglycerol coating (HPG). Plasma activation creates highly reactive surface oxygen moieties that readily react with glycidol. Irrespective of the substrate, coatings are uniform and pinhole free, comprising O─C─O repeats, with HPG chains packing in a fashion that holds reversibly binding proteins at the coating surface. In vitro assays with planar test samples show that HPG prevents platelet adhesion and activation, as well as reducing (>3 log) bacterial attachment and preventing biofilm formation. Ex vivo and preclinical studies show that HPG‐coated nitinol stents do not elicit thrombosis or restenosis, nor complement or neutrophil activation. Subcutaneous implantation of HPG coated disks under the skin of mice shows no evidence of toxicity nor inflammation.