Peng Shi

A multi-stimuli responsive gold nanocage-hyaluronic platform for targeted photothermal and chemotherapy

Noninvasive and pinpointed intracellular drug release that responds to multiple stimulus is still a formidable challenge for cancer therapy. Herein, we reported a multi-stimuli responsive platform based on drug loaded gold nanocages @ hyaluronic acid (AuNCs-HA) for pinpointed intracellular drug release. These well-prepared nanohybrids could specifically recognize cancer cells via HA-CD44 interactions and be efficiently endocytosed by receptor-mediated process. Subsequently, the coated HA molecules could be degraded in lysosomes, resulting in the release of encapsulated drug. In addition, by taking advantage of the excellent photothermal properties, the AuNCs could accelerate the release of encapsulated drug and induce a higher therapeutic efficacy upon near-infrared (NIR) irradiation. In vitro results confirmed that the encapsulated drug could only be pinpointedly released in intracellular environments, which permitted high therapeutic efficacy against cancer cells and minimized the side effects. Importantly, as compared to that of the two therapies independently, a complete inhibition of tumor growth treated with the combination of chemotherapy and photothermal therapy was observed in vivo. Taken together, our present study provides new insights into developing pinpointed, multi-stimuli responsive intracellular drug release systems for synergistic cancer therapy.

pH-responsive NIR enhanced drug release from gold nanocages possesses high potency against cancer cells

We report a smart therapeutic nanoplatform based on Fe(3)O(4)@CaP capped gold nanocages, which integrates magnetic targeting, photothermal therapy and chemotherapy for killing cancer cells. Combining photothermal- and chemo-therapy results in a synergistic effect in cancer treatment.

A Smart “Sense‐Act‐Treat” System: Combining a Ratiometric pH Sensor with a Near Infrared Therapeutic Gold Nanocage

Herein, we design a sense-act-treat system via the combination of a ratiometric pH sensor with a therapeutic gold nanocage. Our design could sense the tumor through two-state switching of fluorescence and further provide chemotherapy and hyperthermia for treating the tumor, showing the potential for future biomedical applications.

Visible-light-driven enhanced antibacterial and biofilm elimination activity of graphitic carbon nitride by embedded Ag nanoparticles

AbstractSemiconductor nanomaterials with photocatalytic activity have potential for many applications. An effective way of promoting photocatalytic activity is depositing noble metal nanoparticles (NPs) on a semiconductor, since the noble metal NPs act as excellent electron acceptors which inhibit the quick recombination of the photoexcited electron-hole pairs and thereby enhance the generation of reactive oxygen species (ROS). Herein, a highly effective platform, graphitic carbon nitride (g-C3N4) nanosheets with embedded Ag nanoparticles (Ag/g-C3N4), was synthesized by a facile route. Under visible light irradiation, the ROS production of Ag/g-C3N4 nanohybrids was greatly improved compared with pristine g-C3N4 nanosheets, and moreover, the nanohybrids showed enhanced antibacterial efficacy and ability to disperse bacterial biofilms. We demonstrate for the first time that the Ag/g-C3N4 nanohybrids are efficient bactericidal agents under visible light irradiation, and can also provide a new way for biofilm elimination. The enhanced antibacterial properties and biofilm-disrupting ability of Ag/g-C3N4 nanohybrids may offer many biomedical applications.n

Cerium oxide caged metal chelator: anti-aggregation and anti-oxidation integrated H2O2-responsive controlled drug release for potential Alzheimer's disease treatment

Metal ions play important roles in Aβ aggregate deposition and neurotoxicity which involves the formation of reactive oxygen species (ROS). Oxidative stress and metal dysregulation have been considered as therapeutic targets for AD. Herein, a novel double delivery platform has been presented by integrated anti-aggregation property of metal chelators and anti-oxidation property of CeO2NPs in one system for Alzheimers disease treatment. Compared with metal chelators or CeO2NPs alone, a synergistic effect is observed in our H2O2-responsive controlled release system. So far, there is no report to use CeO2NP as both capping and antioxidant agent for AD therapy. By taking advantage of good biocompatibility, high selectivity toward toxic metal ions, and their ability to cross the blood–brain barrier (BBB), the two-in-one bifunctional nanoparticles can effectively inhibit Aβ aggregate formation, decrease cellular ROS and protect cells from Aβ-related toxicity.

Nanocomposite Incorporating V2O5 Nanowires and Gold Nanoparticles for Mimicking an Enzyme Cascade Reaction and Its Application in the Detection of Biomolecules

Artificial enzyme mimics are a current research interest, and many nanomaterials have been found to display enzyme-mimicking activity. However, to the best of our knowledge, there have not hitherto been any reports on the use of pure nanomaterials to construct a system capable of mimicking an enzyme cascade reaction. Herein, we describe the construction of a novel nanocomposite consisting of V2O5 nanowires and gold nanoparticles (AuNPs) through a simple and facile chemical method, in which V2O5 and AuNPs possess intrinsic peroxidase and glucose oxidase (GOx)-like activity, respectively. Results suggest that this material can mimic the enzyme cascade reaction of horseradish peroxidase (HRP) and GOx. Based on this mechanism, a direct and selective colorimetric method for the detection of glucose has been successfully designed. Because single-strand and double-strand DNA (ssDNA and dsDNA) have different deactivating effects on the GOx-like activity of AuNPs, the sensing of target complementary DNA can also be realized and disease-associated single-nucleotide polymorphism of DNA can be easily distinguished. Our study opens a new avenue for the use of nanomaterials in enzyme mimetics, and holds promise for the further exploration of nanomaterials in creating alternative catalytic systems to natural enzymes.

Spatiotemporal control of cell-cell reversible interactions using molecular engineering.

Manipulation of cell–cell interactions has potential applications in basic research and cell-based therapy. Herein, using a combination of metabolic glycan labelling and bio-orthogonal click reaction, we engineer cell membranes with β-cyclodextrin and subsequently manipulate cell behaviours via photo-responsive host-guest recognition. With this methodology, we demonstrate reversible manipulation of cell assembly and disassembly. The method enables light-controllable reversible assembly of cell–cell adhesion, in contrast with previously reported irreversible effects, in which altered structure could not be reused. We also illustrate the utility of the method by designing a cell-based therapy. Peripheral blood mononuclear cells modified with aptamer are effectively redirected towards target cells, resulting in enhanced cell apoptosis. Our approach allows precise control of reversible cell–cell interactions and we expect that it will promote further developments of cell-based therapy.

A “Sense‐and‐Treat” Hydrogel Used for Treatment of Bacterial Infection on the Solid Matrix

A sense-and-treat hydrogel is constructed for sensing and inhibiting bacterial infection. Without bacteria, the hydrogel emits green fluorescence. With bacterial infection, the hydrogel emits red fluorescence and releases Vancomycin to kill bacteria.

A cytotoxic amyloid oligomer self-triggered and NIR-enhanced amyloidosis therapeutic system

We report a new strategy for improving the efficiency of non-specific amyloidosis therapeutic drugs by coating amyloid-responsive lipid bilayers. The approach had drawn inspiration from amyloid oligomer-mediated cell membrane disruption in the pathogenesis of amyloidosis. A graphene-mesoporous silica hybrid (GMS)-supported lipid bilayer (GMS-Lip) system was used as a drug carrier. Drugs were well confined inside the nanocarrier until encountering amyloid oligomers, which could pierce the lipid bilayer coat and cause drug release. To ensure release efficiency, use of a near-infrared (NIR) laser was also introduced to facilitate drug release, taking advantage of the photothermal effect of GMS and thermal sensitivity of lipid bilayers. To facilitate tracking, fluorescent dyes were co-loaded with drugs within GMS-Lip and the NIR laser was used once the oligomer-triggered release had been signaled. Because of the spatially and temporally controllable property of light, the NIR-assisted release could be easily and selectively activated locally, by tracking the fluorescence signal. Our design is based on amyloidosis pathogenesis, the cytotoxic amyloid oligomer self-triggered release via cell membrane disruption, for the controlled release of drug molecules. The results may shed light on the development of pathogenesis-inspired drug delivery systems.