Abstract

Graphene oxide (GO)-gelatin (G) aerogels were synthesized via the physical interactions between GO-oxygenated groups and G amine groups to obtain potential hemostatic devices. The influence of the aerogel synthesis conditions-acid and basic GO suspensions-was used to evaluate their clotting performance. These materials were also characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, and thermogravimetric analysis, and their properties of absorption, stiffness, porosity, surface charge, and pore size were measured and compared. The clotting activity of the materials was evaluated by prothrombin time, activated partial thromboplastin time, soluble human P-selectin, and in vitro dynamic clotting assays, as well as their cytotoxicity. GO-G aerogels presented heterogeneous microporous structures with porosities higher than 90% and a high PBS absorption capacity, 49.6 +/- 3.8 g(PBS)/g(aerogel) for positively charged aerogels (15.63 +/- 0.5 mV) and 42.75 +/- 2.38 g(PBS)/g(aerogel) for negatively charged aerogels (-20.53 +/- 1.07 mV). Comparatively, positively charged aerogels had superior structural properties to negatively charged aerogels, such as stiffness, porosities, and pore sizes, because they promote H bonding. In regard to hemostatic activity, negatively charged aerogels had higher clotting performance, reaching 95.6% clotted blood, and therefore provide a suitable structure for the coagulation process and promote clot formation without using common mechanisms. In addition, negatively charged aerogels were not cytotoxic and promoted fibroblast proliferation. Therefore, negatively charged GO-G aerogels may be a potential hemostatic device that can be used as a wound dressing. (C) 2020 Elsevier Ltd. All rights reserved.