Stimuli responsive drug delivery systems based on nano-graphene for cancer therapy

Multifunctional Peptide-Amphiphile End-Capped Mesoporous Silica Nanoparticles for Tumor Targeting Drug Delivery

A tumor targeting redox-responsive drug delivery system (DDS) with bioactive surface was constructed by immobilizing peptide-based amphiphile C12-CGRKKRRQRRRPPQRGDS (defined as ADDA-TCPP) onto the mesoporous silica nanoparticles (MSNs) as an end-capping nanovalve, which consists of two main segments: a hydrophobic alkyl chain ADDA and a hydrophilic amino acid sequence containing a Tat_48-60 peptide sequence with a thiol terminal group and an RGDS targeting ligand, via a disulfide linkage for redox-triggered intracellular drug delivery. A series of characterizations confirmed that the nanosystem had been successfully fabricated. The antitumor drug doxorubicin (DOX) was selected as a model drug and efficiently trapped in the pores of MSNs, and an in vitro release experiment demonstrated that the mesopores of the resulting DOX-loaded MSNs (DOX@MSN-ss-ADDA-TCPP) could be sealed tightly with ADDA-TCPP self-assemblies through hydrophobic interactions between the alkyl chains; the resulting DDS exhibited "zero premature release" of DOX in the physical environment. However, a burst drug release was triggered by a high concentration of glutathione (GSH) in simulated cellular cytosol. Moreover, detailed investigations confirmed that incorporation of RGDS peptide facilitated the active targeting delivery of DOX to α_vβ₃ integrin overexpressed tumor cells, and Tat_48-60 modification on MSNs could enhance intracellular drug delivery, exhibiting an obvious toxicity to tumor cells. The multifunctional nanosystem constructed here can realize the controlled drug release and serve as a platform for designing multifunctional nanocarriers using diversified bioactive peptide-based amphiphile.

Antibacterial mechanisms of graphene-based composite nanomaterials

Pathogenic bacteria are gaining resistance to conventional antibiotics at an alarming rate due to overuse and rapid transfer of resistance genes between bacterial populations. As bacterial resistance to antibiotics causes millions of fatalities worldwide, it is of urgent importance to develop a new class of antibiotic materials with both broad-spectrum bactericidal activity and suitable biocompatibility. Graphene derivatives are rapidly emerging as an extremely promising class of antimicrobial materials due to their diverse bactericidal mechanisms and relatively low cytotoxicity towards mammalian cells. By combining graphene derivatives with currently utilized antibacterial metal and metal-oxide nanostructures, composite materials with exceptional bactericidal activity can be achieved. In this review, the antibacterial activities of graphene derivatives as well as their metal and metal-oxide composite nanostructures will be presented. The synthetic methodology for these various materials will be briefly mentioned, and emphasis will be placed on the evaluation of their mechanisms of action. This information will provide a valuable insight into the current understanding of the interactions governing the microbial toxicity of graphene-based composite nanostructures.

Effective thermal transport properties in multiphase biological systems containing carbon nanomaterials

Here we report computational results from an off-lattice Monte Carlo investigation of the effective thermal transport properties in multiphase biological systems containing carbon nanomaterials.

Dual-responsive core-crosslinked polyphosphoester-based nanoparticles for pH/redox-triggered anticancer drug delivery

The paper focuses on the preparation of biodegradable pH/redox dual-responsive core-crosslinked nanoparticles loaded with dual anticancer drugs PTX and DOX via synergetic electrostatic as well as hydrophobic interactions and their further application in tumor chemotherapy.

Facile fabrication of a resveratrol loaded phospholipid@reduced graphene oxide nanoassembly for targeted and near-infrared laser-triggered chemo/photothermal synergistic therapy of cancer in vivo

A resveratrol-loaded phospholipid coated reduced graphene oxide was prepared using a sonication method.

SPIONs/DOX loaded polymer nanoparticles for MRI detection and efficient cell targeting drug delivery

Reducible polydopamine coated magnetic nanoparticles (SPIONs@PDA) for both magnetic resonance imaging (MRI) detection and cell targeting drug delivery.

Serum-resistant, reactive oxygen species (ROS)-potentiated gene delivery in cancer cells mediated by fluorinated, diselenide-crosslinked polyplexes

Fluorinated, diselenide-crosslinked polyplexes were developed to enable ROS-responsive and serum-resistant gene delivery in cancer cells.

Interactions of graphene with mammalian cells: Molecular mechanisms and biomedical insights

Carbon-based functional nanomaterials have attracted immense scientific interest from many disciplines and, due to their extraordinary properties, have offered tremendous potential in a diverse range of applications. Among the different carbon nanomaterials, graphene is one of the newest and is considered the most important. Graphene, a monolayer material composed of sp²-hybridized carbon atoms hexagonally arranged in a two-dimensional structure, can be easily functionalized by chemical modification. Functionalized graphene and its derivatives have been used in diverse nano-biotechnological applications, such as in environmental engineering, biomedicine, and biotechnology. However, the prospective use of graphene-related materials in a biological context requires a detailed comprehension of these materials, which is essential for expanding their biomedical applications in the future. In recent years, the number of biological studies involving graphene-related nanomaterials has rapidly increased. These studies have documented the effects of the biological interactions between graphene-related materials and different organizational levels of living systems, ranging from biomolecules to animals. In the present review, we will summarize the recent progress in understanding mainly the interactions between graphene and cells. The impact of graphene on intracellular components, and especially the uptake and transport of graphene by cells, will be discussed in detail.