A tightly bonded reduced graphene oxide coating on magnesium alloy with photothermal effect for tumor therapy

Abstract

Photothermal therapy becomes a hotspot in the treatment of bone tumors. Magnesium and its alloys are regarded as potential bone implants for their favorable mechanical property and biodegradable in vivo . However, there is few research devoted to fabricating a photothermal coating on Mg alloy. In the present study, reduced graphene oxide coating with a strong photothermal effect was prepared on the surface of AZ31 via two steps. Firstly, graphene oxide coating was deposited on the surface via electrophoresis deposited (GO#), followed by a reduction process of the graphene oxide coating in ultrapure water (rGO#). GO# and rGO# coatings were characterized by SEM, Raman, XRD, FTIR, and XPS. The results revealed that, compared with GO# coating, the content of oxygen-containing (C O/C O-C, C=O, O C=O) groups on rGO# coating was significantly decreased. rGO# coating was found tightly adhered to AZ31 substrate. According to the first-principles calculations, the well-bonded heterostructure between MgO and rGO is the main reason for the strong bonding force. Moreover, the prepared rGO# coating showed a superior photothermal effect, which brings a new strategy to the treatment of bone tumors with Mg-based implants. Preparation of rGO coated AZ31 alloy via EPD and self-reduction processes