ROS- and pH-Responsive Polydopamine Functionalized Ti3C2Tx MXene-Based Nanoparticles as Drug Delivery Nanocarriers with High Antibacterial Activity

Abstract

Premature drug release and poor controllability is a challenge in the practical application of tumor therapy, which may lead to poor chemotherapy efficacy and severe adverse effects. In this study, a reactive oxygen species (ROS)-cleavable nanoparticle system (MXene-TK-DOX@PDA) was designed for effective chemotherapy drug delivery and antibacterial applications. Doxorubicin (DOX) was conjugated to the surface of (3-aminopropyl)triethoxysilane (APTES)-functionalized MXene via an ROS-cleavable diacetoxyl thioketal (TK) linkage. Subsequently, the surfaces of the MXene nanosheets were coated with pH-responsive polydopamine (PDA) as a gatekeeper. PDA endowed the MXene-TK-DOX@PDA nanoparticles with superior biocompatibility and stability. The MXene-TK-DOX@PDA nanoparticles had an ultrathin planar structure and a small lateral size of approximately 180 nm. The as-synthesized nanoparticles demonstrated outstanding photothermal conversion efficiency, superior photothermal stability, and a remarkable extinction coefficient (23.3 L g−1 cm−1 at 808 nm). DOX exhibited both efficient ROS-responsive and pH-responsive release performance from MXene-TK-DOX@PDA nanoparticles due to the cleavage of the thioketal linker. In addition, MXene-TK-DOX@PDA nanoparticles displayed high antibacterial activity against both Gram-negative Escherichia coli (E. coli) and Gram-positive Bacillus subtilis (B. subtilis) within 5 h. Taken together, we hope that MXene-TK-DOX@PDA nanoparticles will enrich the drug delivery system and significantly expand their applications in the biomedical field

Reactive Oxygen Species (ROS)‐Assisted Nano‐Therapeutics Surface‐Decorated with Epidermal Growth Factor Fragments for Enhanced Wound Healing

“…Our results were similar to previous studies, in which the binding and collapse of TK could be confirmed by elemental analysis and the changes in molecular weight. [ 34–37 ] UHR‐SEM demonstrated that although the shapes of the samples showed no noticeable difference, the thickness of NFs slightly increased from 1.36 to 1.70 µm consequent to the decoration of PEG@TK on the surface of NFs (Figure 3d). However, the presence of EGFfr did not affect the fiber thickness because EGFfr molecules have a low molecular weight and low loading density on the surface of NFs.…”

MXene: A wonderful nanomaterial in antibacterial

“…When applied to a therapeutic animal model, it effectively promoted angiogenesis and facilitated wound healing. Zhang et al ( Zhang et al, 2022 ) designed a ROS- and pH-responsive composite system (MXene-TK-DOX@PDA nanoparticles) in which drugs were coupled to MXene-based nanocarriers via covalent bonding, which could avoid premature drug release, enhance loading capacity, and reduce adverse effects. In addition, coupling pH-responsive polydopamine on the surface of MXene-based nanoplatforms effectively improves the photothermal conversion ability.…”

Potential Biosafety of Mxenes: Stability, Biodegradability, Toxicity and Biocompatibility

“…[91] However, in many cases MXenes are equally toxic to both types of bacteria. [31,32,74,75,90] This may be due to additional mechanisms of action. In particular, MXenes can bind to lipopolysaccharides and prevent nutrient absorption.…”

“…[18][19][20][21] In part, the anti-inflammatory effect can be explained by the antioxidant properties, which are confirmed by some studies of MXenes as mimetics of antioxidant enzymes. [22][23][24][25] In addition, MXenes are effectively applied for photothermal, sonodynamic, and thermogaseous therapy of cancer, [26][27][28][29][30] construction of nanoplatforms that deliver/release drugs, [24,[30][31][32] and in tissue regeneration studies. [33][34][35][36] In addition, they have significant potential for use in bioimaging.…”