Simply and Cheaply Prepared Liposomal Membrane for Nanocarriers: High Encapsulation Efficiency Based on Broad Regulation of Surface Charges and pH-Switchable Performance.

The zeta potential of nanoparticles impacts their distribution and metabolism in the body as well as their interaction with medications of varying charges, hence altering therapeutic efficacy and safety. In this paper, the external charges of liposomes were regulated by utilizing a simple and economical method based on competition for protons of cationic chitosan (CS) and anion hyaluronic acid (HA). The charge regulation of a liposomal membrane is generally accomplished by adjusting the ratio of charged lipids within a liposome (e.g., cationic DOTAP or anionic DOPS), the stability of which was maintained by the coating materials of cationic chitosan (CS) or anion hyaluronic acid (HA). A series of nanoparticles could respond to pH-stimulation with adjustable surface charge. Moreover, the sizes of liposomes coated with CS and HA remain within a narrow range. In vitro cytotoxicity tests revealed that the nanocarriers were safe, and the nanoparticles containing antitumor medicines were efficient in tumor therapy. Considering liposomes with different external surface charges could be aimed at diverse therapy purposes. The strategies for regulating liposomal surface charges with high encapsulation rates and certain release cycles reported here could provide a versatile platform as carriers for the delivery of drugs and other macromolecules into human bodies.

Single or pluralistic? The game and balance of China's community governance policy tools.

BACKGROUND: Policy tools embody policy concepts and are essential to achieving policy objectives. The effective allocation of policy tools directly impacts the effectiveness of community governance and determines the modernization process of grassroots governance. We aim to analyze the logic of community governance policy tool selection, and then provide assistance for the modernization of grassroots governance. METHODS: We selected 100 national and provincial government work reports and 63 policy documents related to community governance during China's "12th Five-Year Plan" to "14th Five-Year Plan" period as analysis samples. And build an analysis framework based on the three dimensions of time, space, and tools. We used Nvivo.20 software for text encoding analysis. RESULTS: Based on the model framework, we analyze the results as follows. From the perspective of the time dimension, among the five types of policy tools, the proportion of command-type policy tools used showed a downward trend, from 88.16% in the 12th Five-Year Plan to 83.50% in the 14th Five-Year Plan. However, motivation-type and persuasion-type tools showed an upward trend, rising from 1.34% and 5.26% in the 12th Five-Year Plan period to 3.40% and 8.74% in the 14th Five-Year Plan respectively. The system-change-type policy tools decreased from 1.32% in the 12th Five-Year Plan to 0.97% in the 14th Five-Year Plan. The proportion of capacity-building-type policy tools has gradually increased from 2.63% in the 12th Five-Year Plan to 4.85% in the 14th Five-Year Plan. From the perspective of spatial dimension, apart from command and persuasion policy tools, the usage frequency of the other three types of policy tools in the three major regions all display a "growth-decline-growth" trend. From the perspective of tool dimension, command-type policy tools are dominant in China's community governance, with a cumulative frequency of 1405 times and a high proportion of 81.75%. Apart from command policy tools, persuasive policy tools and capacity-building policy tools have a relatively high proportion, with usage frequencies of 186 and 78 respectively. CONCLUSIONS: We found that current community governance policy tools mainly consist of command tools. However, there is a trend towards combining tools such as command, persuasion, incentive, capacity building, and system change in the future. There is a typical contradiction between instrumental rationality and value rationality, indicating an evolution from instrumental rationality to the integration of instrumental and value rationality. This study addresses the conflict of policy tools through rational guidance of values, the rational guarantee of tools, and cooperation to achieve the goal of high-quality development of community governance.