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As a novel two-dimensional material, Ti3C2 MXenes has attracted lots of attention in biomedical filed for its large surface area and excellent near-infrared (NIR) responsiveness. In this paper, an in-situ growth and self-assembly approach was employed to combine gold nanorods (GNRs) with Ti3C2 nanosheets to prepare intelligent sandwich-like Ti3C2@GNRs/PDA/Ti3C2 nanohybrids. Compared with Ti3C2 nanosheets, in-situ growth Ti3C2@GNRs possessed excellent photothermal conversion efficiency (45.89%), caused by the distinguished photothermal synergy between GNRs and Ti3C2 nanosheets. Moreover, the high specific surface area of Ti3C2 MXene and outstanding adhesion performance of PDA endowed Ti3C2@GNRs/PDA/Ti3C2 nanohybrids with superior drug loading ability for doxorubicin hydrochloride (DOX) (95.88%). Besides, Ti3C2@GNRs/PDA/Ti3C2 nanohybrids displayed distinct pH/NIR responsive drug release properties upon NIR irradiation owing to the strong π-π stacking interaction between Ti3C2@GNRs/PDA/Ti3C2 and DOX, along with the excellent NIR-responsiveness of Ti3C2@GNRs/PDA/Ti3C2. This paper offers a practicable method to prepare Ti3C2 MXene-based nanoplatform with synergistically enhanced NIR drug release behavior, brilliant biocompatibility and high drug loading efficiency, which is expected to be applied in remote cancer therapy.

Antibacterial nanomaterials produced by sustainable or ‘green’ synthesis methods are very important. Moreover, combination of photocatalytic antibacterial materials and antiseptic inorganic nanopar...

With the development of aquaculture, there is an urgent demand for an alternative antibacterial agent to reduce the drug resistance and environmental pollution caused by the abuse of antibiotics. Recently, silver nanoparticles (AgNPs) have been viewed as a novel type of antimicrobial agents due to their unique advantages. In this study, AgNPs were biosynthesized with the ginger rhizomes extract. The biosynthesized AgNPs were characterised by UV–visible spectroscopy, transmission electron microscopy, X-ray diffraction and fourier transform infrared spectroscopy. Furthermore, the antimicrobial activities of the AgNPs were fully analyzed against six typical aquatic pathogens. The results indicated that the components in ginger extract could function as the chemical reductant to synthesize AgNPs. Moreover, compared with the AgNPs synthesized by chemical methods, the biosynthesized AgNPs were smaller, and had higher stability and antibacterial activity. Therefore, the biosynthesized AgNPs using ginger extract may have prospective applications in aquaculture.

New materials with good antibacterial activity synthesized by simple, environmentally friendly method have attracted numerous research interests. Taking advantage of Ag and graphene oxide (GO), the GO/Ag nanocomposites were prepared by a facile, green “one-pot” reaction to achieve superior antibacterial properties. AgNO3 is as a precursor of Ag nanoparticles (Ag NPs), and the grape seeds extract as an environmentally friendly reducing and stabilizing agent. The as-prepared GO/Ag nanocomposites were characterized by various technologies. The results indicated that the silver ion was reduced by the grade seeds extract and Ag NPs were decorated on the surface of GO nanosheets successfully. The average size of the Ag NPs anchored on the GO surface was 40–50 nm. In this study, we prepared GO/Ag nanocomposites with different Ag NPs to GO ratios and carefully investigated their antibacterial activities. We found that the GO/Ag nanocomposites show better antibacterial activity when the concentration of AgNO3 is 2 mM. GO/Ag nanocomposites have a minimum inhibitory concentration 23.8 μg/mL, lower than bare Ag NPs 25.5 μg/mL. We try to explain the antibacterial mechanism based on optical microscopy observation.

With the development of aquaculture, there is an urgent demand for an alternative antibacterial agent to reduce the drug resistance and environmental pollution caused by the abuse of antibiotics. Recently, as promising antimicrobial agents, silver nanoparticles (AgNPs) synthesized via organisms has received much attention. Cordyceps militaris , a valuable edible and medicinal fungus, is rich in a variety of biologically active substances. So, it is of interest to biosynthesis a new antimicrobial agent of AgNPs with the aid of C. militaris . In this study, AgNPs were synthesized using the cell filtrate of C. militaris mycelium as reducing agents. The formation of AgNPs was first confirmed by the surface plasmon resonance illustrated in UV–visible spectrophotometer. X-ray diffraction analysis further confirmed that the AgNPs were composed of highly crystalline Ag. Transmission electron microscopy analysis revealed that most the AgNPs were in spherical shape with mean diameter about 15 nm. Moreover, the synthesized AgNPs exhibited superior antibacterial activities against the all the aquatic as well as clinical pathogenic bacteria. Besides, the prepared AgNPs were proven to be highly stable, even after long-term storage. To the best of our knowledge, this is the first report that the C. militaris extract could facilitate the synthesis of AgNPs.

Here, we construct a three-dimensional artificial nanoforest consisting of p-type narrow-band-gap CuO nanowires as tree trunks and polar facet regulatory n-type wide-band-gap ZnO nanodisks (NDs) as tree leaves through a two-step hydrothermal process on Cu mesh. Such heterostructure device performs a synergistic-effect enhanced photocatalytic activity with stable recyclability for the reduction of hexavalent chromium Cr(VI). The improved photocatalytic activity and durability were attributed to the well-steered transfer of photogenerated carriers accelerated by built-in electric field, the extension of solar absorption realized by bandgaps integrated heterostructure and proliferative active sites induced by ZnO NDs with high ratio of polar surface. This work provides a new approach to design versatile devices for solar energy conversion.

The most promising strategies to overcome bacterial drug resistance are the use of nanoparticles (NPs). In this paper, the extract of Gynostemma pentaphyllum Makino was prepared and used as reducing as well as stabilising agent to obtain silver NPs (AgNPs). The active phytochemicals present in the herb were responsible for the quick reduction in silver ion (Ag+) to metallic AgNPs (Ag0). The method is green and rapid, and the whole synthesis process can be finished within 15 min at 60°C. An intense surface plasmon resonance band in 420–450 nm range clearly revealed the formation of AgNPs. The obtained AgNPs were further characterised using X-ray diffraction, transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and zeta potential. Moreover, the as prepared AgNPs have a superior antibacterial activity against four kinds of aquatic pathogenic bacteria, which shows great potential in aquaculture field.

The development of new type of antimicrobials without drug-resistence has increased exponentially. “One pot” green synthesis method was developed to synthesize the graphitic-phase C 3 N 4 (g-C 3 N 4 ) loaded with metal Ag nanoparticles (Ag NPs) using grape seed extract as reducing agent and stabilizing agent, which is rapid, economic and environmentally friendly. Ag NPs and g-C 3 N 4 sheets have strong interaction between Ag atoms and –C–N–, –C=N– bonds in g-C 3 N 4 sheets, resulting in successful deposition of AgNPs on g-C 3 N 4 sheets. The as-prepared g-C 3 N 4 /Ag nanocomposite shows better antibacterial activity than the green synthesized bare Ag NPs, showing great promise in application for new antibacterial material.