Development of graphene-based materials as antimicrobial additives for 3D polymers

Abstract

The goal of the diploma thesis was to achieve antibacterial properties by graphene materials themselves, enhancement due doping of graphene materials by Ag(I) and Cu(I)-ions, or enhancement due deposition of Ag-NP, Cu-NP, Cu/Cu2O-NP, Cu2(OH)3Cl-NP (copper oxychloride) on graphene oxide and integration into different kind of resins that could be polymerised using 3D printing. Materials with antibacteral properties could be used as alternative medical devices such as dental aerosol exhausters, plastic masks, or different kind of prothesis and implants. The main purpose is to achieve good antimicrobial properties while mechanical and printing properties of polymers would not deteriorate due modification and graphene material additions. Graphene oxide was produced via electrochemical exfoliation of graphite rods. The graphene oxide was reduced and modified by the materials mentioned above. The versatile graphene modifications were mixed with two different resins that are commonly used in 3D printing for medical devices namely the LT Dental and the Standard Grey resins. Rectangular and cubic formations were 3D printed under well-defined conditions. The produced graphene oxide modifications were characterised via several methods such as Raman spectroscopy, SEM/EDX, XRD spectroscopy. Furthermore, on the polymer composites different kinds of antimicrobial property analysis were carried out such as OD600 measurements for screening, subsequent well plate analysis, LDH cytotoxicity assay, Cellular ROS assay and Presto Blue Cell Viability Reaction, respectively. The characterization of the novel graphene oxide modifications was very promising, and the composites were stable over a longer period. However, after the application to polymers the antibacterial property analysis was not showing so high effectiveness than the one in the literature [1], so the process of the additive manufacturing needs to be improved and changed in order to achieve better results.