In this work, magnetic Fe 3 O 4 nanoparticles treated with (3-aminopropyl)triethoxysilane were used as immobilization material. Lipase was covalently bound to the amino-functionalized magnetic nanoparticles by using glutaraldehyde as a coupling reagent with the activity recovery up to 70% and the enzyme binding efficiency of 84%. The binding of lipase to the magnetic particles was confirmed by enzyme assays, transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectra. Moreover, the immobilized lipase was found to be able to catalyze the transesterification of soybean oil with methanol to produce fatty acid methyl esters (better known as biodiesel). Besides, it was determined that the conversion of soybean oil to biodiesel fuels reached over 90% by the three-step addition of methanol when 60% immobilized lipase was employed. Further study showed that the immobilized lipase could be used four times without significant decrease of activity.

The direct ethanol fuel cells in an alkaline medium have a broad vision of applications because of their large energy density, reasonable power density, and environmentally friendly features. Herein, we present a facile one-step method to synthesize PdAg nanosheet assemblies (NSAs) in a mixed solution of N,Ndimethylformamide and water with the addition of molybdenum hexacarbonyl and cetyltrimethylammonium bromide. Pure Pd NSA shows an irregular shape while PdAg NSAs gradually undergo a process from solid assembly to a hollow structure with the Pd/Ag molar ratio changing from 3:1 to 2:1 to 1:1. The formation of alloy nanosheets in the assemblies combined with the introduction of Ag in the Pd catalyst enhances the catalytic activity toward ethanol electrooxidation from 1524 mA mg −1 of pure Pd NSA to 1866 mA mg −1 of PdAg NSA with a Pd/Ag molar ratio of 2:1. On the basis of the experimental data, compared with pure Pd structures, both the nature of a thin nanosheet of PdAg NSAs and the structural changes in the alloy assemblies play key roles in determining the electrocatalytic activity of these Pd-based catalysts.

Telluride molybdenum (MoTe 2 ) nanosheets with wide near-infrared (NIR) absorbance are functionalized with polyethylene glycol-cyclic arginine-glycineaspartic acid tripeptide (PEG-cRGD). After loading a chemotherapeutic drug (doxorubicin, DOX), MoTe 2 -PEG-cRGD/DOX is used for combined photothermal therapy and chemotherapy. With the high photothermal conversion efficiency, MoTe 2 -PEG-cRGD/DOX exhibits favorable cells killing ability under NIR irradiation. Owing to the cRGD-mediated specific tumor targeting, MoTe 2 -PEG-cRGD/DOX shows efficient accumulation in tumors to induce a strong tumor ablation effect. MoTe 2 -PEG-cRGD nanosheets, which are relatively stable in the circulation, could be degraded under NIR ray. The in vitro and in vivo experimental results demonstrate that this theranostic nanoagent, which could accumulate in tumors to allow photothermal imaging and combined therapy, is readily degradable in normal organs to enable rapid excretion and avoid long-term retention/toxicity, holding great potential to treat tumor effectively.

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Some new mixed ligand complexes (1-5) of type ML'B (M(II)=Mn(II), Co(II), Ni(II), Cu(II) and Zn(II); HL'= o-vanillidene-2-aminobenzothiazole; B= 1,10-phenanthroline) and Schiff base metal complexes of types (ML2") (6-10) and (M2L") (11-15) (HL"= o-vanillidene-2-amino-N-(2-pyridyl)-benzene sulfonamide) were synthesized and characterized by elemental analysis and spectral (IR, 1H NMR and 13C NMR) studies. The free ligands and their metal complexes have been screened for their in vitro biological activities against bacteria, fungi and yeast. The metal complexes show more potent activities compared with Schiff base ligands.