Boron nitride quantum dots are obtained by a facile sonication-solvothermal technique. They are proven to be promising fluorescent bioimaging probes for bioimaging with remarkably low cytotoxicity and easily integrated into high-performance proton exchange membranes. This work will probably trigger research interest in BN and its new applications in a variety of fields.

A facile poly(vinylpyrrolidone) (PVP)-assisted exfoliation method is utilized to simultaneously exfoliate and noncovalently modify MoSe2 nanosheets. The resultant hydrophilic nanosheets are shown to be promising candidates for biocompatible photothermal therapy (PTT) agents, and they could also be encapsulated into a hydrogel matrix for some intelligent devices. This work not only provides novel insights into exfoliation and modification of transition metal dichalcogenide (TMD) nanosheets but also might spark more research into engineering multifunctional TMD-related nanocomposites, which is in favor of further exploiting the attractive properties of these emerging layered two-dimensional (2D) nanomaterials.

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The application of nanomaterials in intelligent drug delivery is developing rapidly for treatment of cancers. In this paper, we fabricated a new kind of protease/redox/pH stimuli-responsive biodegradable nanohydrogels with methacrylic acid (MAA) as the monomer and N,N-bis(acryloyl)cystamine (BACy) as the cross-linker through a facile reflux-precipitation polymerization. After that, the polyethylene glycol (PEG) and folic acid (FA) were covalently grafted onto the surface of the nanohydrogels for enhancement of their long in vivo circulation lifetime and active targeting ability to the tumor cells and tissues. This kind of nanohydrogels could be disassembled into short polymer chains (Mn<1140; PDI<1.35) both in response to glutathione (GSH) through reduction of the sensitive disulfide bonds and protease by breakage of the amido bonds in the cross-linked networks. The nanohydrogels were utilized to simultaneously load both hydrophilic drug doxorubicin (DOX) and hydrophobic drug paclitaxel (PTX) with high drug loading efficiency. The cumulative release profile showed that the drug release from the drug-loaded nanohydrogels was significantly expedited by weak acidic (pH 5.0) and reducing environment (GSH), which exhibited an distinct redox/pH dual stimuli-responsive drug release to reduce the leakage of drugs before they reach tumor site. In addition, the in vitro experiment results indicated that the multidrug-loaded system had synergistic effect on cancer therapy. Meanwhile, the acute toxicity and intravital fluorescence imaging studies were adopted to evaluate the biocompatibility and biotoxicity of the nanohydrogels, the experimental results showed that the PEG modification could greatly enhance the long in vivo circulation lifetime and reduce the acute toxicity (LD50: from 138.4 mg/kg to 499.7 mg/kg) of the nanohydrogels.

Utilizing fluorescence reporters and SERS probes as the security labels, a series of dual-mode encoded magnetic composite microspheres with micrometer size was designed and prepared for anticounterfeiting applications. At first, the micro-meter-sized melamine formaldehyde microspheres with different fluorescence molecules (FMF) were prepared by precipitation polymerization, and then the magnetite composite microspheres (FMF/MNPs) were fabricated by direct immobilization of magnetic nanoparticles (MNPs) onto the surface of FMF microspheres. After deposition of Ag nanoparticles (Ag-NPs) onto FMF/MNPs microspheres, the SERS probes were absorbed onto the surface of Ag-NPs, and then a protection layer of silica was coated on the composite microspheres by Stöber method. The combination of different fluorescence reporters and SERS probes greatly increased the encoding complexity and volume for high-level anticounterfeiting. The structure of the dual-encoded FMF/MNPs/Ag-NPs/SiO2 composite microspheres was characterized by FESEM, TEM, FLS(fluorescence spectrometer), XRD, VSM, UV-vis and EDS. The embedded magnetic nanoparticles enable the composite microspheres to be quickly isolated from the marked latex paint by magnet at the concentration of as low as 1 ppm, and the covert tag information can be read out even from one composite microsphere. In addition, the covert security information in the marked coating film can be also read out in situ and the existence of the composite microspheres does not influence the visible appearance of the coating film. All the above outstanding properties will make these dual-mode encoded composite microspheres as advanced security tags for next-generation anticounterfeiting applications.

The anticancer therapy on the basis of reactive oxygen species (ROS)-mediated cellular apoptosis has achieved great progress. However, this kind of theraputic strategy still faces some challenges such as light, photosensitizer and oxygen (O) dependence. In this article, a ROS-mediated anticancer therapy independent of light, photosensitizer and oxygen was established based on a Fe-induced ROS-generating nanosystem. First, artemisinin (ART) was loaded in porous magnetic supraparticles (MSP) by a nanodeposition method. Then, the poly(aspartic acid)-based polymer, which consisted of dopamine, indocyanine green, and polyethylene glycol side chain, was coated onto the surface of ART-loaded MSP. When the nanoparticles entered into cancer cells, a reaction of Fe-mediated cleavage of the endoperoxide bridge contained in ART occurred and subsequent a large amount of ROS was generated. Moreover, a NIR light was used to effectively increase the local temperature of tumor in virtue of the superior photothermal effects of MSP, which enabled us to accelerate the ROS generation and achieved an enhanced ROS yield. The newly developed nanodrug system displayed a high level of intracellular ROS generation, leading to the desired killing efficacy against malignant cells and solid tumor. This smart nanosystem holds great potential to overcome the existing barrier in PDT and opens a promising avenue for anticancer therapy.

The one-step synthesis of nanoscale conjugated microporous polymer (NCMP) capsules is presented by using PMAA microspheres as self-sacrificial templates. Precise control over the morphology, nanostructure and shell thickness makes the NCMPs have a tunable NIR absorption ability and a shape-dependent photothermal conversion efficiency. Upon exposure to 808 nm light, they rapidly generate heat (NCMP concentration: 100 μg mL(-1)) and cause thermal ablation of HeLa cells with less than 10% viability.

Biodegradable materials used for drug delivery are of great demand due to their ability to degrade into low molecular weight species and further excrete from the body by metabolism. Herein, we report a new kind of zinc(II) crosslinked poly(methacrylic acid) nanohydrogels (ZCLNs) inspired by zinc finger proteins with dual stimuli-triggered degradation (glutathione and pH) for the first time. Compared with the disulfide bond crosslinked nanohydrogels, this new kind of ZCLNs is beneficial to the degradation of a wide range of cells, including normal cells. Ex vivo fluorescence images showed that the DOX-loaded folate-PEG conjugated zinc(II)-crosslinked polymeric nanohydrogels (FPZCLNs-15) preferentially accumulated in tumor tissue and the accumulation in normal tissues was much less compared with DOX-loaded PZCLNs-15 (non-targeted nanohydrogels) and free DOX, the FPZCLNs-15 (targeting system) delivered DOX to the tumor site with approximately 3.6- and 1.6-fold higher than free DOX and PZCLNs-15, respectively. Meanwhile, the PZCLNs-15 and FPZCLNs-15 reduced the concentration of DOX in the heart by 3.2- and 5.0-fold respectively, as compared to the free DOX. Moreover, a superior tumor growth inhibition and negligible damage to normal organs like the heart and kidney, which is reported to be vulnerable to DOX-associated side effects, are further demonstrated.