MXene-Graphene Composites: A Perspective on Biomedical Potentials

Abstract

MXenes, transition metal carbides and nitrides with graphene-like structures, have received considerable attention since their first discovery. On the other hand, Graphene has been extensively used in biomedical and medicinal applications. MXene and graphene, both as promising candidates of two-dimensional materials, have shown to possess high potential in future biomedical applications due to their unique physicochemical properties such as superior electrical conductivity, high biocompatibility, large surface area, optical and magnetic features, and extraordinary thermal and mechanical properties. These special structural, functional, and biological characteristics suggest that the hybrid/composite structure of MXene and graphene would be able to meet many unmet needs in different fields; particularly in medicine and biomedical engineering, where high-performance mechanical, electrical, thermal, magnetic, and optical requirements are necessary. However, the hybridization and surface functionalization should be further explored to obtain biocompatible composites/platforms with unique physicochemical properties, high stability, and multifunctionality. In addition, toxicological and long-term biosafety assessments and clinical translation evaluations should be given high priority in research. Although very limited studies have revealed the excellent potentials of MXene/graphene in biomedicine, the next steps should be toward the extensive research and detailed analysis in optimizing the properties and improving their functionality with a clinical and industrial outlook. Herein, different synthesis/fabrication methods and performances of MXene/graphene composites are discussed for potential biomedical applications. The potential toxicological effects of these composites on human cells and tissues are also covered, and future perspectives toward more successful translational applications are presented. The current state-of-the-art biotechnological advances in the use of MXene-Graphene composites, as well as their developmental challenges and future prospects are also deliberated. Due to the superior properties and multifunctionality of MXene-graphene composites, these hybrid structures can open up considerable new horizons in future of healthcare and medicine.

Keywords: Biocompatibility; Biomedical engineering; Cancer theranostics; Composites; Graphene; Hybrid structures; MXene.

Fig. 1

MXene-graphene hybrids with fascinating physicochemical properties/features can be considered as promising candidates for biomedical explorations

Fig. 2

The preparative process of MXene-reduced graphene oxide (RGO) hybrid aerogels through GO-assisted hydrothermal assembly technique followed by directional-freezing and freeze-drying processes. Reproduced with permission from Ref. [24]. Copyright 2018 American Chemical Society

Fig. 3

The preparative process of graphene oxide (GO) via the water electrolytic oxidation process. Reproduced with permission from Ref. [39]

Fig. 4

A The preparative processes of MXene nanosheets and B MXene-graphene hybrid films for the immobilization of enzymes with glucose biosensing application. LiF—Lithium fluoride; DMSO—Dimethyl sulfoxide; GC—Glassy carbon; GOx—Glucose oxidase. Reproduced with permission from Ref. [60]. Copyright 2019 American Chemical Society

Fig. 5

The potential mechanism of toxicity to human cells upon exposure to graphene-based materials