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Graphitic-phase carbon nitride (g-C

Chemodynamic therapy (CDT) utilizes iron-initiated Fenton chemistry to destroy tumor cells by converting endogenous H2 O2 into the highly toxic hydroxyl radical (. OH). There is a paucity of Fenton-like metal-based CDT agents. Intracellular glutathione (GSH) with . OH scavenging ability greatly reduces CDT efficacy. A self-reinforcing CDT nanoagent based on MnO2 is reported that has both Fenton-like Mn2+ delivery and GSH depletion properties. In the presence of HCO3- , which is abundant in the physiological medium, Mn2+ exerts Fenton-like activity to generate . OH from H2 O2 . Upon uptake of MnO2 -coated mesoporous silica nanoparticles (MS@MnO2 NPs) by cancer cells, the MnO2 shell undergoes a redox reaction with GSH to form glutathione disulfide and Mn2+ , resulting in GSH depletion-enhanced CDT. This, together with the GSH-activated MRI contrast effect and dissociation of MnO2 , allows MS@MnO2 NPs to achieve MRI-monitored chemo-chemodynamic combination therapy.

Multifunctional nanocomposites have the potential to integrate sensing, diagnostic, and therapeutic functions into a single nanostructure. Herein, we synthesize Fe3O4@polydopamine core–shell nanocomposites (Fe3O4@PDA NCs) through an in situ self-polymerization method. Dopamine, a melanin-like mimic of mussel adhesive proteins, can self-polymerize to form surface-adherent polydopamine (PDA) films onto a wide range of materials including Fe3O4 nanoparticles used here. In such nanocomposites, PDA provides a number of advantages, such as near-infrared absorption, high fluorescence quenching efficiency, and a surface for further functionalization with biomolecules. We demonstrate the ability of the Fe3O4@PDA NCs to act as theranostic agents for intracellular mRNA detection and multimodal imaging-guided photothermal therapy. This work would stimulate interest in the use of PDA as a useful material to construct multifunctional nanocomposites for biomedical applications.

In this work, we discovered that polypyrrole nanoparticles (PPy NPs) displayed a low non-specific protein adsorption. We herein present the first PPy NP-based biosensing platform for intracellular mRNA detection in living cells. We also demonstrate that PPy NPs exhibit high NIR absorbance and can be utilized for cancer photothermal therapy.

Multifunctional nanocomposites have the potential to integrate sensing, diagnostic, and therapeutic functions into a single nanostructure. Herein, we synthesize Fe3O4@polydopamine core-shell nanocomposites (Fe3O4@PDA NCs) through an in situ self-polymerization method. Dopamine, a melanin-like mimic of mussel adhesive proteins, can self-polymerize to form surface-adherent polydopamine (PDA) films onto a wide range of materials including Fe3O4 nanoparticles used here. In such nanocomposites, PDA provides a number of advantages, such as near-infrared absorption, high fluorescence quenching efficiency, and a surface for further functionalization with biomolecules. We demonstrate the ability of the Fe3O4@PDA NCs to act as theranostic agents for intracellular mRNA detection and multimodal imaging-guided photothermal therapy. This work would stimulate interest in the use of PDA as a useful material to construct multifunctional nanocomposites for biomedical applications.

Graphitic-phase carbon nitride (g-C3N4) nanosheets, the newly emerging two-dimensional (2D) layered nanomaterials, have been demonstrated to be promising bioimaging agents due to their high photoluminescence (PL) quantum yields, good biocompatibility and low toxicity. However, the therapeutic applications of g-C3N4 nanosheets have not been explored until now. In this study, we have proven for the first time that g-C3N4 nanosheets can be used as efficient photosensitizers for photodynamic tumor therapy and as pH-responsive nanocarriers for drug delivery. On one hand, as photosensitizers, g-C3N4 nanosheets are able to generate reactive oxygen species (ROS) and kill cancer cells efficiently under low-intensity light irradiation (20 mW cm-2). On the other hand, as nanocarriers, g-C3N4 nanosheets possess an ultrahigh drug-loading capacity owing to their high surface-to-volume ratio. More importantly, g-C3N4 nanosheets loaded with the anticancer drug doxorubicin (DOX) exhibit a pH-responsive release property which is beneficial for the delivery of DOX into cancer cells for chemotherapy. Furthermore, due to their high PL quantum yields, the fluorescent g-C3N4 nanosheets can enable visualization of the delivery. These findings demonstrated the potential of g-C3N4 nanosheets as low-toxic and biocompatible photosensitizers and pH-responsive drug nanocarriers for biomedical applications.