A highly sensitive fluorescence "on-off-on" sensing platform for captopril detection based on AuNCs@ZIF-8 nanocomposite.

Here, a novel fluorescent sensing strategy is established for the detection of captopril (CP) sensitively on the basis of a nanocomposite of gold nanoclusters (AuNCs) and metal-organic framework (AuNCs@ZIF-8). The aggregation-induced emission (AIE) effect will be triggered when AuNCs is encapsulated by metal-organic framework (MOF) which served as a carrier since it limits the molecular motion of AuNCs, and the fluorescence of AuNCs greatly enhanced about 5-time after forming the nanocomposites of AuNCs@ZIF-8. The strong orange-emission at 562 nm was quenched in the presence of mercury ions through dynamic quenching. After adding captopril, the quenched fluorescence of AuNCs@ZIF-8/Hg2+ system would be restored due to the specific interaction among captopril with mercury ions. Simultaneously, the restored degree of AuNCs@ZIF-8/Hg2+ fluorescence depended on the concentration of captopril. Hence, with AuNCs@ZIF-8 serving as reporter signal, the captopril content can be monitored by an "on-off-on" fluorescence sensing mode with a linear relationship of 1-100 µM, and the limit of detection for captopril was 0.134 µM.

The influence of health information attention and app usage frequency of older adults on persuasive strategies in mHealth education apps.

With the development of mobile communication technology, persuasive technology is widely used in mobile health. Using personalized persuasive strategies in mobile health education (MHE) apps can effectively improve users' health literacy and health behaviors. The transtheoretical model explains the process of user behavior change. Different usage frequency of the app reflects changes in user behavior. However, few studies have examined how the perceived importance of persuasive strategies among older adults changes with increasing use frequency. In this study, we analyzed the sensitivity of 111 older adults in China to persuasive strategies in MHE apps. Thirteen persuasive strategies were selected for this study. A repeated measure analysis of variance (RM-ANOVA) was used to demonstrate the influence of gender, health information attention and frequency of use on the sensitivity of perceived persuasive strategies among older adults. The results revealed older adults with a high usage frequency of health apps were more receptive to persuasive strategies, especially in social comparison strategy. This result may help developers consider factors such as the frequency of use by older users when designing personalized persuasive strategies for MHE apps.

Saegusa Oxidation of Enol Ethers at Extremely Low Pd-Catalyst Loadings under Ligand-free and Aqueous Conditions: Insight into the Pd(II)/Cu(II)-Catalyst System.

A highly efficient and practical Pd(II)/Cu(OAc)2-catalyst system of Saegusa oxidation, which converts enol ethers to the corresponding enals with a number of diverse substrates at extremely low catalyst loadings (500 mol ppm) under ligand-free and aqueous conditions, is described. Its synthetic utility was demonstrated by large-scale applications of the catalyst system to important nature molecules. This work allows Saegusa oxidation to become a highly practical approach to preparing enals and also suggests new insight into the Pd(II)/Cu(II)-catalyst system for dehydrogenation of carbonyl compounds and decreasing Pd-catalyst loadings.