Carbon nitride supported copper nanoparticles: light-induced electronic effect of the support for triazole synthesis.

The composite framework of graphitic carbon nitride (gCN) supported copper nanoparticle can act as a high-performance photoreactor for the synthesis of 1,2,3-triazole derivatives under light irradiation in the absence of alkaline condition. The photoactivity of gCN originates from an electron transition from the valence band to the conduction band, in the presence of photon energy, and the hot electron acts as a scavenger of the terminal proton of the alkyne molecule to facilitate the formation of copper acetanilide complex. In this study, we have performed the experiment under a different photonic environment, including dark condition, and in the presence and absence of base. A comparative study was also executed using Cu-TiO2 system, as a reference material, in the support of our proposed mechanism. The recycling performance and the photocorrosion effect of the catalyst have also been reported in this study.

A polymer supported Cu(I) catalyst for the 'click reaction' in aqueous media.

Polymer stabilized monovalent copper has been synthesized using an in situ chemical transformation route and was characterized by means of different microscopic, optical and surface characterization techniques, which offered information about the chemical structure of the polymer and the morphology of the complex. The supramolecular material, Cu(i)-poly(2-aminobenzoic acid), denoted Cu(i)-pABA, showed catalytic activity for the cycloaddition reaction between terminal alkynes and azides to synthesize 1,2,3-triazoles with excellent yields. The catalyst was recovered from the reaction mixture and recycled several times without an appreciable loss of catalytic activity. The whole strategy was done under ambient conditions and in the presence of water as a solvent.

In situ generation of a high-performance Pd-polypyrrole composite with multi-functional catalytic properties.

We report on a bottom up approach for the synthesis of a Pd-polypyrrole nanocomposite material. The composite material was characterized by means of different techniques, such as UV-vis, IR, and Raman spectroscopy, which offered information about the chemical structure of the polymer, whereas electron microscopy images provided information regarding the morphology of the composite material and the distribution of the metal particles in the polymer matrix. During the synthesis of the nanocomposite, the Pd nanoparticles act as a catalyst for a model proton-coupled electron transfer reaction. The Pd-polypyrrole nanocomposite material was also used as a catalyst for the electro-catalytic detection of tryptophan, a precursor for some neurotransmitters.

Inhibition of hepatitis B virus replication in vivo using lipoplexes containing altritol-modified antiviral siRNAs.

Chronic infection with the hepatitis B virus (HBV) occurs in approximately 6% of the world's population and carriers of the virus are at risk for complicating hepatocellular carcinoma. Current treatment options have limited efficacy and chronic HBV infection is likely to remain a significant global medical problem for many years to come. Silencing HBV gene expression by harnessing RNA interference (RNAi) presents an attractive option for development of novel and effective anti HBV agents. However, despite significant and rapid progress, further refinement of existing technologies is necessary before clinical application of RNAi-based HBV therapies is realized. Limiting off target effects, improvement of delivery efficiency, dose regulation and preventing reactivation of viral replication are some of the hurdles that need to be overcome. To address this, we assessed the usefulness of the recently described class of altritol-containing synthetic siRNAs (ANA siRNAs), which were administered as lipoplexes and tested in vivo in a stringent HBV transgenic mouse model. Our observations show that ANA siRNAs are capable of silencing of HBV replication in vivo. Importantly, non specific immunostimulation was observed with unmodified siRNAs and this undesirable effect was significantly attenuated by ANA modification. Inhibition of HBV replication of approximately 50% was achieved without evidence for induction of toxicity. These results augur well for future application of ANA siRNA therapeutic lipoplexes.