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The combined use of photothermal therapy (PTT) and photodynamic therapy (PDT) could circumvent the drawbacks of each individual therapeutic strategy, resulting in an enhanced antitumor effect. However, the lack of highly effective photo-agents that are irradiation-safe in the biologically transparent window hinder the advancement of phototherapy clinically. Hence, in this study, a charge separation engineering strategy was adopted to fabricate a nanoplatform with heterojunctions, namely, in situ TiO2-loaded MXene (Ti3C2/TiO2 heterojunctions). This nanoplatform exhibited reduced bandgap (1.68 eV), enhanced NIR-II photothermal conversion efficiency (44.98%), and extended absorption edge compared to pristine TiO2 for enhanced photodynamic effect. More importantly, the proliferation of tumor cells could be efficiently inhibited at a 5 mm chicken breast depth after 1064 nm laser irradiation, and the intracellular ROS production significantly increased under 660 nm or even 1064 nm laser irradiation with heterojunctions (HJs) compared with that of TiO2. Moreover, the in vivo data further confirmed that the as-prepared heterojunctions could efficiently eradicate tumors efficiently via improved photothermal effect with NIR-II laser irradiation and upregulated ROS production. Collectively, the reported HJs strategy provides an opportunity for the success of combinational PTT and PDT therapy in tumor treatment. [ABSTRACT FROM AUTHOR]

A peptide/DNA nanocomplex was developed for the targeted delivery of chemotherapeutics and photosensitizers to cancer cells for efficient combination therapy. The chemotherapeutic drug doxorubicin (DOX) and the photosensitizer 5,10,15,20-tetra-(1-methylpyridine-4-yl)-porphyrin (TMPyP4) were physically incorporated by an aptamer (AS1411)-modified tetrahedral DNA nanostructure, where the tetrahedral DNA and aptamer-induced G-quadruplex provide binding sites of DOX and TMPyP4. The co-loaded 3A-TDN/DT displayed a targeted uptake by HeLa cancer cells through the high affinity and specificity between AS1411 and nucleolin, a protein overexpressed on many types of cancer cells. A polycationic polymer, mPEG-PAsp(TECH), was synthesized to complex with the DNA nanostructure to efficiently escape from lysosomes via the proton sponge effect upon the enhanced internalization by tumor cells. Under the irradiation of 660 nm laser light, TMPyP4 induced an upregulation of intracellular reactive oxygen species, which combined with DOX to fulfill the efficient inhibition of HeLa cells. Our study demonstrated a biocompatible peptide/DNA composite nanoplatform for combinational cancer therapy via the targeted delivery of therapeutic agents and efficient lysosomal escape. [ABSTRACT FROM AUTHOR]

Photodynamic therapy would suffer from low efficiency in the cancer treatment process if the reactive oxygen species (ROS) generated from a photosensitizer (PS) were reduced by intracellular glutathione (GSH). To overcome this limitation, in this work, we developed an amphiphilic branched copolymer with pendant vinyl groups, and it self-assembled with chlorin e6 (Ce6) into nanoparticles to fabricate a GSH-reaction response drug delivery system. The vinyl groups in the hydrophobic core of the nanoparticles were reacted with GSH by a "thio–ene" click reaction to release Ce6; simultaneously, the level of GSH decreased for enhanced PDT. Both in vitro and in vivo studies demonstrated that remarkable PDT efficacy for the nanosystem can be achieved. [ABSTRACT FROM AUTHOR]

Flexible smart materials have attracted a lot of attention in material science, especially in biomaterials and wearable devices. In this study, silk composites with high electroconductivity and biocompatibility were prepared based on a facile slight dissolution technique that reduces weak structures and a nanoscale manipulation of silk fibers, which allows more pyrrole penetration and deposition. The composite resistivity and conductivity are 0.021 ± 0.002 Ω m and 0.47 ± 0.03 S cm−1, respectively. Morphology studies and elemental analysis clearly showed that polypyrrole (PPy) distributed the outer and inner silk fibers homogeneously, which contributed to the improvement of the electroconductivity and electric heating properties. The silk/PPy composite supported PC12 cell growth and development as well. These silk/PPy composites with highlighted features provide favourable candidates for biomedical products and wearable devices. [ABSTRACT FROM AUTHOR]

A novel coumarin hydrozone compound which exhibits piezochromic luminescence upon grinding was prepared. The piezofluorochromic properties were reversible upon fuming or heating. The intermolecular hydrogen bonds have been observed by single-crystal X-ray structural analysis, which are believed to make a major contribution to the piezofluorochromic properties. [ABSTRACT FROM AUTHOR]