Promoting Role of MXene Nanosheets in Biomedical Sciences: Therapeutic and Biosensing Innovations.

MXene nanosheets have emerged as biocompatible transition metal structures, which illustrate desirable performance for various applications due to their unique structural, physicochemical, and compositional features. MXenes are currently expanding their usage territory from mechanical, optical, chemical, and electronic fields toward biomedical areas. This is mainly originated from their large surface area and strong absorbance in near-infrared region, which in combination with their facile surface functionalization with various polymers or nanoparticles, make them promising nanoplatforms for drug delivery, cancer therapy, precise biosensing and bioimaging. The facile surface modification of the MXenes can mediate the better in vivo performance of them through reduced toxicity, enhanced colloidal stability, and extended circulation within the body. Herein, the synthesis and state-of-the-art progresses of MXene nanosheets designed for biomedical applications, including structural- and dose-dependent antimicrobial activity, photothermal therapy, drug delivery, and implants are emphasized. Furthermore, biosensing applications are highlighted and a comprehensive discussion on photoacoustic imaging, magnetic resonance imaging, computed tomography imaging, and optical imaging of MXenes is presented. The challenges and future opportunities of applying MXene nanomaterials in the area of biomedicine are also discussed.