Using Graphene-Based Materials for Stiff and Strong Poly(ethylene glycol) Hydrogels.

Helena P Ferreira,Fernão D Magalhães,Inês C Gonçalves,Duarte Moura,Patrícia C Henriques,Cristina C Barrias,Andreia T Pereira

doi:10.3390/ijms23042312

Abstract

Blood-contacting devices are increasingly important for the management of cardiovascular diseases. Poly(ethylene glycol) (PEG) hydrogels represent one of the most explored hydrogels to date. However, they are mechanically weak, which prevents their use in load-bearing biomedical applications (e.g., vascular grafts, cardiac valves). Graphene and its derivatives, which have outstanding mechanical properties, a very high specific surface area, and good compatibility with many polymer matrices, are promising candidates to solve this challenge. In this work, we propose the use of graphene-based materials as nanofillers for mechanical reinforcement of PEG hydrogels, and we obtain composites that are stiffer and stronger than, and as anti-adhesive as, neat PEG hydrogels. Results show that single-layer and few-layer graphene oxide can strengthen PEG hydrogels, increasing their stiffness up to 6-fold and their strength 14-fold upon incorporation of 4% w/v (40 mg/mL) graphene oxide. The composites are cytocompatible and remain anti-adhesive towards endothelial cells, human platelets and Staphylococcus aureus, similar to neat hydrogels. To the best of our knowledge, this is the first work to report such an increase of the tensile properties of PEG hydrogels using graphene-based materials as fillers. This work paves the way for the exploitation of PEG hydrogels as a backbone material for load-bearing applications.

Highlights

Introduction iationsCardiovascular diseases (CVD) are the number one cause of death worldwide, and, every year, approximately 17.9 million people die from it, according to the World HealthOrganization [1]
GOsizes and oxidation degrees were explored as nanofillers for the mechanical reinforcement of Poly(ethylene glycol) (PEG) hydrogels, reduced forms—
graphene-based materials (GBM) of different thicknesses, lateral sizes and oxidation degrees were explored as few-layer (FLG)—and oxidized forms—graphene oxide (GO) reduced and few-layer nanofillersgraphene for the mechanical reinforcement of PEG hydrogels, graphene oxide (FLGO)

Summary

Introduction

Introduction iationsCardiovascular diseases (CVD) are the number one cause of death worldwide, and, every year, approximately 17.9 million people die from it, according to the World HealthOrganization [1]. Cardiovascular diseases (CVD) are the number one cause of death worldwide, and, every year, approximately 17.9 million people die from it, according to the World Health. CVD include various conditions, namely coronary or peripheral artery diseases, cerebrovascular disease (stroke), valvular diseases, heart failure and venous thromboembolism [2]. Most of these are managed through alterations to lifestyle, medication, minimally-invasive interventions or surgery. Blood-contacting devices (BCD) are an increasingly important resource for the management of some CVD, including prosthetic heart valves (for valvular diseases), stents and vascular grafts (for coronary and peripheral artery disease) and ventricular assist devices (for treatment of heart failure), among others [3]. The combined global market of these BCD is estimated at USD 32 billion and is predicted to grow in the coming years [4–7].

Methods

Results

Discussion

Conclusion