No abstract

Surface plasmons, a unique property of metal nanoparticles, have been widely applied to enhance the performance of optical and electrical devices. In this study, a high quality zinc oxide (ZnO) thin film was grown on a quartz substrate by a radio frequency magnetron sputtering technique, and a metal-semiconductor-metal structured ultraviolet detector was prepared on the ZnO film. The responsivity of the photodetector was enhanced from 0.836 to 1.306 A/W by sputtering metal (Pt) nanoparticles on the surface of the device. In addition, the absorption of the ZnO thin film was enhanced partly in the ultraviolet band. It is revealed that Pt nanoparticles play a key role in enhancing the performance of the photodetectors, where surface plasma resonance occurs.

Starch-based nanoparticles participate in the stimulus-responsive Pickering emulsion for recyclable catalysis.

In this study, a brand new biocatalytic system was successfully accomplished by combination of metal–organic frameworks (MOFs) biomimetic mineralization and Pickering interfacial system for enhanced lipase catalysis and recycling in organic media. Specifically, a highly porous lipase-loaded MOF composite was synthesized via biomimetic mineralization of ZIF-8 around lipase from Candida rugosa (CRL). With increasing enzyme loading amount, the role of CRL in modulating size, crystallinity, and interior or exterior structure of the composite was meticulously clarified. In this process, we disclosed a gradation from the crystal into an amorphous form for CRL-loaded ZIF-8 and more importantly discovered an enrichment of enzymes on the surface of the crystals. Combining this phenomenon with results of dynamic light scattering, zeta potential, and water contact angle, as well as styrene-induced interface solidification, we confirmed the surface-embedded CRL of the crystal played a role in adjusting the surface chemical characteristics of the composite that directly affected the stability of the emulsion and the distribution rule of stabilizers on the oil–water interface. Furthermore, through the comparison of hydrolyses involving a small substrate (p-nitrophenyl butyrate) and a larger one (p-nitrophenyl palmitate), a stable oil-in-water Pickering emulsion with an optimized quantity and integrity of oil droplets was proved to achieve the highest catalytic efficiency. Notably, because size selectivity of the ZIF-8 shell induced different locations of the substrates in contact with the enzymes, an obvious discrepancy in catalysis efficiency was observed for substrates with different sizes. Impressively, we could employ this system for transesterification by changing only the encapsulated enzyme (lipase B from Candida antarctica expressed in Aspergillus) and optimizing the oil/water ratio. The excellent catalytic performance highlighted the versatility of this interfacial biocatalytic system.

Activated platelets play a substantial role in Alzheimer's disease (AD) and atherothrombosis. Mean platelet volume (MPV) is an early marker of platelet activation, which is linked to a variety of pro-thrombotic and pro-inflammatory diseases. This study is to examine the association between platelet indices and vascular dementia (VaD) and AD. In this cross-sectional study, we investigated the levels of platelet count, MPV, and platelet distribution width (PDW) in 150 VaD patients, 110 AD patients, and 150 non-demented controls. MPV and PDW were significantly lower in patients with VaD and AD as compared with controls. The decrease in PDW for AD patients as compared with VaD patients was also significant (p < 0.001). In addition, there was a positive correlation between Mini-Mental State Examination (MMSE) and MPV and PDW, after adjusting confounding factors (r = 0.532 for MPV and r = 0.425 for PDW, p < 0.001 for both). Multivariate regression analysis showed that MPV and PDW were significantly associated with MMSE (β = 0.366 for MPV and β = 0.273 for PDW, p < 0.001 for both). In conclusion, MPV and PDW were both decreased in VaD and AD. PDW levels were significantly lower in AD as compared to those in VaD. Our findings suggest that PDW in combination with MMSE scores could be potential indicators for distinguishing VaD from AD.