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Quantum dots (QDs) are increasingly being utilized as near infrared (NIR) active photothermal agents for cancer diagnosis and therapy, with the main emphasis of current research being the enhancement of photothermal conversion efficiencies. Herein, we report the facile synthesis of 2-3 nm boron quantum dots (B QDs), which demonstrated a remarkable photothermal conversion efficiency of 57% under NIR excitation. This outstanding performance can be attributed to the alteration of the electronic structure, which was a result from the distorted edge-effect induced by the unique empty orbit of B atoms in the B QDs. These results can be verified by B K-edge near edge X-ray absorption fine structure (NEXAFS), high-resolution transmission electron microscopy (HR-TEM) and density functional theory (DFT) calculations. The results demonstrate that B QDs represent a promising new and non-toxic agent for both multimodal NIR-driven cancer imaging and photothermal therapy. This work thus identifies B QDs as an exciting new and theranostic agent for cancer therapy. Furthermore, the synthetic strategy used here to synthesize the B QDs was simple and easily scalable.Benzo[e][1,2,4]triazinyl, or Blatter radicals, are stable free radicals, first reported by Blatter in 1968. In contrast to their nitroxide counterparts, their properties can be modified more widely and more easily through simple substitution changes. This, together with recent developments in their synthesis, now places them at the forefront of developing applications in functional materials. Herein, we survey the various methods to synthesise and customise Blatter radicals, highlighting key developments in the last decade that have transformed their utility. We then outline their important spectroscopic, structural, electrochemical, magnetic and chemical properties and how these depend on their chemical structure and morphology. Finally, we review their growing list of applications including as sensors, spin labels, magnetic materials, liquid crystals and in polymer and small molecule synthesis.The recognition and detection of dicarboxylic acids and dicarboxylates is of significance for a wide variety of applications, including medical diagnosis, monitoring of health and of environmental contaminants, and in industry. Hence small molecule receptors and sensors for dicarboxylic acids and dicarboxylates have great potential for applications in these fields. This review outlines the challenges faced in the recognition and detection of these species, strategies that have been used to obtain effective and observable interactions with dicarboxylic acids and dicarboxylates, and progress made in this field in the period from 2014 to 2020.Developing new strategies to enhance drug accumulation in the tumor and therapeutic efficacy is of great importance in the field of tumor therapy. Herein, a peanut-like multifunctional nanomedicine (CuS-PGH NMs) made of CuS nanoparticles encapsulated in poly(l-lysine)(PLL)/glucose oxidase (GOx)-hyaluronic acid (HA) shells has been constructed via layer-by-layer (LbL) assembly, and shows good biocompatibility and effective multi-gradient therapy. Because of the enhanced permeability and retention (EPR) effect, the CuS-PGH NMs could significantly enhance the cellular uptake by tumors overexpressing CD44 receptors, which respond to hyaluronidase (HAase)-triggered surface charge conversion. Once internalized by the tumor, GOx was the first to be exposed and could effectively deplete endogenous glucose for starvation therapy, and the excess H2O2 was then converted into highly toxic hydroxyl radicals (˙OH) via a Cu+-mediated Fenton-like reaction for chemodynamic therapy (CDT). Meanwhile, the as-obtained Cu+ ions accompanied the regenerated less-active Cu2+ ions. Interestingly, the high content of H2O2 could, in turn, accelerate Cu2+/Cu+ conversion to promote the Cu+-H2O2 reaction for enhanced chemodynamic therapy (CDT), thereby achieving efficient tumor growth suppression via synergistic starvation/CDT therapy. Subsequently, owing to the strong NIR-II absorption capability of CuS-PGH NMs, effective photothermal tumor ablation of the weakened tumor cells could be realized with the precise guidance of NIR-II PAI. This multi-gradient therapeutic strategy has been demonstrated to have excellent antitumor activity with minimal nonspecific damages, and offers a new avenue to precise tumor therapy.Bioactive hydrogels based on naturally-derived polymers are of great interest for regenerative medicine applications. Among naturally-derived polymers, silk fibroin has been extensively explored as a biomaterial for tissue engineering due to its unique mechanical properties. Here, we demonstrate the rapid gelation of cell-laden silk fibroin hydrogels by visible light-induced crosslinking using riboflavin as a photo-initiator, in presence of an electron acceptor. The gelation kinetics were monitored by in situ photo-rheometry. Gelation was achieved in minutes and could be tuned owing to its direct proportionality to the electron acceptor concentration. The concentration of the electron acceptor did not affect the elastic modulus of the hydrogels, which could be altered by varying the polymer content. Further, the biocompatible riboflavin photo-initiator combined with sodium persulfate allowed for the encapsulation of cells within silk fibroin hydrogels. To confirm the cytocompatibility of the silk fibroin formulations, three cell types (articular cartilage-derived progenitor cells, mesenchymal stem cells and dental-pulp-derived stem cells) were encapsulated within the hydrogels, which associated with a viability >80% for all cell types. selleck inhibitor These results demonstrated that fast gelation of silk fibroin can be achieved by combining it with riboflavin and electron acceptors, which results in a hydrogel that can be used in tissue engineering and cell delivery applications.Fmoc-dipeptides are a class of short aromatic peptides featuring eminent supramolecular self-assembly, which is due to the aromaticity of the Fmoc group, which improves the association of peptide building blocks. This study aimed to introduce a new dipeptide hydrogel scaffold, Fmoc-phenylalanine-valine (Fmoc-FV), for 3D culture of various cells. Peptide hydrogel scaffolds were prepared by the pH-titration method in various concentrations and temperatures, and characterized by spectroscopic methods, including circular dichroism, attenuated total reflection FT-IR and fluorimetry. Mechanical behaviors such as thixotropy and temperature-sensitivity were investigated by oscillatory rheology. The Fmoc-FV hydrogels were then applied in 3D-culture of WJ-MSCs (mesenchymal stem cells), HUVECs (normal endothelial cells), and MDA-MB231 (tumor cell line) by live-dead fluorescence microscopy and Alamar blue viability assay experiments. The results confirmed that the β-sheet structure is principally interlocked by π-π stacking of the Fmoc groups and entangled nanofibrous morphologies as revealed by FE-SEM.