Functionalized MoS₂-Based Nanomaterials for Cancer Phototherapy and Other Biomedical Applications

Transition-metal dichalcogenides (TMDs), as a novel category of nanomaterials and a potential alternate to graphene, are attracting great interest of researchers, because of their strong conductivity, superior catalytic performance, and good optical properties. As the most representative type of all TMDs, molybdenum disulfide (MoS2)-based nanomaterials are expanded into two-dimensional (2D) nanosheets, quantum dots (QDs), flower-like nanoparticles, nanospheres and nanotubes. These types are regarded as promising nanoplatforms for various applications in biomedicine, such as drug delivery, phototherapy, biosensing, bioimaging, theranostics, and antimicrobials, because of the unique planar structures, superb electronic and optical properties (such as thickness-dependent bandgap, strong near-infrared absorbance, and large surface area), and easily functionalized surface sites. Until now, there have been a few reviews about MoS2-based nanomaterials, with regard to functionalization for improvement of properties, such as high drug loading efficiency, dispersibility, physiological stability, biocompatibility, targeting ability, pharmacodynamics, controllable drug release, enhanced treatment and therapeautic efficacy, and even biodegradability and toxicity reduction. Here, we systematically summarized the progress of functionalized MoS2-based nanomaterials with improved physicochemical and biological properties for the biomedical applications. First, we emphatically introduced these biomedical applications in drug delivery, anticancer photothermal therapy (PTT), photodynamic therapy (PDT), and combined phototherapy. Besides, other biomedical applications were also introduced in detail including bioimaging, biosensing, theranostics, toxicity, tissue engineering, and antimicrobials. Lastly, the current challenges, opportunities and prospects of MoS2-based nanomaterials were also discussed in depth. We expect that this review will contribute to a quick and in-depth understanding of the latest progress in bioapplication of MoS2-based nanomaterials, inspiring the creation of various techniques to design and fabricate MoS2-based nanomaterials with multiple capability and high biological safety, and expand them into more application in the field of biomedicine.