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In this work, the synthesis of high-performance, metal ion-imprinted, mesoporous carbon electrocatalysts for hydrazine oxidation reaction (HzOR) using casein or a family of phosphoproteins derived from cow's milk as a precursor is shown. The synthesis is made possible by mixing trace amounts of non-noble metal ions (Fe 3+ or Co 2+ ) with casein and then producing different metal ions-functionalized casein intermediates, which upon carbonization, followed by acid treatment, lead to metal ionimprinted catalytically active sites on the materials. The materials effectively electrocatalyze HzOR with low overpotentials at neutral pH and exhibit among the highest electrocatalytic performances ever reported for carbon catalysts. Their catalytic activities are also better than the corresponding control material, synthesized by carbonization of pure casein and other materials previously reported for HzOR. This work demonstrates a novel synthetic route that transforms an inexpensive protein to highly active carbon-based electrocatalysts by modifying its surfaces with trace amounts of non-noble metals. The types of metal ions employed in the synthesis are found to dictate the electrocatalytic activities of the materials. Notably, Fe 3+ is found to be more effective than Co 2+ in helping the conversion of casein into more electrocatalytically active carbon materials for HzOR.

Ionic liquid-modified cellulose nanowhiskers are synthesized and successfully used as precursors to make heteroatom-doped carbon catalysts.

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In the present study, nanofiber meshes (NFs), composed of polycaprolactone and poly[(2-dimethylamino)ethyl methacrylate] at 80/20 and 50/50 PCL/PDMAEMA blend ratios, were obtained through electrospinning. Silver nanoparticles (AgNPs) formed in situ were then immobilized on NF surfaces through adsorption processes at different pHs. It was possible to observe that the amount of NF-AgNPs can be tuned by changing the pH of AgNPs immobilization and the PCL/PDMAEMA ratio in the blend. The neat NF and NF-AgNPs were characterized with respect to their morphology and mechanical properties. The effects of AgNPs on the antibacterial activities and cytotoxicity of meshes were also evaluated. The antibacterial performance of such NF was improved by the presence of AgNPs. The NF-AgNPs presented good antibacterial effect against S. aureus and partial toxicity against E. coli and P. aeruginosa. Also, compared with neat PCL/PDMAEMA the NF-AgNPs presented lower cytotoxicity against VERO cells, showing their potential for applications in tissue engineering for different types of cell growth.

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An inorganic/organic hybrid material with triggering mechanism for specific drug delivery at colon is demonstrated. First, hydroxyapatite nanowhiskers (n-HA) with high aspect ratio, narrow particle size distribution and high surface area, ca. 67 m 2 /g, are prepared. As a proof-of-concept, terbinafine, a fungicidal agent, is loaded onto the n-HA, obtaining a drug loading of 40.63 mg of terbinafine per gram of n-HA. Hydroxyapatite nanowhiskers loaded with terbinafine are encapsulated with chondroitin sulfate (CS) microspheres, using chemically modified glycidyl methacrylate by performing ultrasonic microemulsion polymerization. The obtained hybrid materials were characterized by TEM, SEM, FTIR, and NMR. Dispersed n-HA in CS microspheres are obtained for different n-HA contents, from 1 to 10% (%w/w). Terbinafine release from hybrid microspheres is caried out by in vitro studies in simulated gastric fluid and simulated intestinal fluid. The studies demonstrated that sustained drug release can be obtained using the developed hybrid material.