Poly-l-lysine-modified reduced graphene oxide stabilizes the copper nanoparticles with higher water-solubility and long-term additively antibacterial activity

Near infrared (NIR) laser mediated surface activation of graphene oxide nanoflakes for efficient antibacterial, antifungal and wound healing treatment

Photothermal treatment of graphene oxide (GO) for antibacterial, antifungal and controlling the wound infection treatment using near infrared laser (NIR, Nd-YAG (λ=1064 nm) were reported. Various pathogenic bacteria (Pseudomonas aeruginosa, Staphylococcus aureus) and fungi (Saccharomyces cerevisiae and Candida utilis) were investigated. The cytotoxicity was measured using the proteomic analysis by matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS), optical density (OD600), standard microdilution procedures, transmission electron microscopy (TEM) and epifluorescence microscopy. The laser mediated the surface activation of GO offer high efficiency for antifungal and antibacterial. Wide broad cells with various instruments approved that graphene oxide is promising material for nanomedicine in the near future.

An electrochemical sensor for the sensitive determination of phenylethanolamine A based on a novel composite of reduced graphene oxide and poly(ionic liquid)

The preparation for a novel composite of RGO–PIL and its electrochemical sensor for sensitive detecting phenylethanolamine A.

Synthesis of copper graphene materials functionalized by amino acids and their catalytic applications

Graphene oxide and its derivative have attracted extensive interests in many fields, including catalytic chemistry, organic synthesis, and electrochemistry, recently. We explored whether the use of graphene after chemical modification with amino acids to immobilize copper nanoparticles could achieve a more excellent catalytic activity for N-arylation reactions. A facile and novel method to prepare copper supported on amino-acid-grafted graphene hybrid materials (A-G-Cu) was first reported. The as-prepared hybrid materials were characterized by a variety of techniques, including Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, atomic force microscopy, transmission electron microscopy, and inductively coupled plasma-atomic emission spectrometry. The results showed that the morphology, distribution, and loading of copper nanoparticles could be well-adjusted by controlling the type of amino acids grafted on graphene. Moreover, most A-G-Cu hybrid materials could catalyze N-arylation of imidazole with iodobenzene with yields more than 90%, while the copper supported on graphene (G-Cu) displayed a yield of just 65.8%. The high activity of A-G-Cu can be ascribed to the good synergistic effects of copper nanoparticles (Cu NPs) and amino-acid-grafted graphene.

The use of poly(methacrylic acid) nanogel to control the release of amoxycillin with lower cytotoxicity

In order to control the release of amoxycillin (AM) with lower cytotoxicity and higher activity, ethylene glycol dimethacrylate was used as the cross-linker, and a series of poly(methacrylic acid) (PMAA) nanogels were prepared to load the AM. Then, the morphology, size, in vitro release property, long-term antibacterial performance, cytotoxicity, stability and activity of this novel AM/PMAA nanogel were investigated. The results showed that the AM/PMAA nanogel sustainably released AM with long-term antibacterial activity. Moreover, the AM/PMAA nanogel could improve the stability of AM. More importantly, this AM/PMAA nanogel showed slighter cytotoxicity than AM alone, suggesting that the AM/PMAA nanogel was a more useful dosage form than AM for infectious diseases.

Design and in vitro evaluation of a novel poly(methacrylic acid)/metronidazole antibacterial nanogel as an oral dosage form

To overcome the undesirable side-effects of metronidazole (MTZ), ethylene glycol dimethacrylate is used as the cross-linker, and a series of poly(methacrylic acid) (PMAA) nanogels were prepared to load the MTZ. We investigated the morphology, size, in vitro release property in the simulated gastrointestinal medium, long-term antibacterial performance against Bacteroides fragilis, cytotoxicity, stability and activity of this novel MTZ/PMAA nanogel. The results indicate that the MTZ/PMAA nanogel sustained the release of MTZ in long-term antibacterial activity in the simulated gastrointestinal medium. This MTZ/PMAA nanogel exhibits less cytotoxicity than MTZ alone, suggesting that MTZ/PMAA nanogel is a more useful dosage form than MTZ for mild-to-moderate Clostridium difficile infections. The novel aspects of this study include the synthesis of a nanogel and the three-phase study of the release profile, which might be useful for other researchers in this field.

Assessment of the toxic potential of graphene family nanomaterials

Graphene, a single-atom-thick carbon nanosheet, has attracted great interest as a promising nanomaterial for a variety of bioapplications because of its extraordinary properties. However, the potential for widespread human exposure raises safety concerns about graphene and its derivatives, referred to as graphene-family nanomaterials. This review summarizes recent findings on the toxicological effects and the potential toxicity mechanisms of graphene-family nanomaterials in bacteria, mammalian cells, and animal models. Graphene, graphene oxide, and reduced graphene oxide elicit toxic effects both in vitro and in vivo, whereas surface modifications can significantly reduce their toxic interactions with living systems. Standardization of terminology and the fabrication methods of graphene-family nanomaterials are warranted for further investigations designed to decrease their adverse effects and explore their biomedical applications.

Macroporous antibacterial hydrogels with tunable pore structures fabricated by using Pickering high internal phase emulsions as templates

Pickering-based antibacterial hydrogels with tunable pore structures were fabricated by using high internal phase emulsion templates.