Microencapsulation of multi-component traditional Chinese herbs extracts and its application to traditional Chinese medicines loaded textiles.

Extracts of traditional Chinese herbs (TCH) contain a variety of anti-allergic, anti-inflammatory and other bioactive factors. However, the defect of easy degradation or loss of active ingredients limits its application in traditional Chinese medicines (TCM) loaded textiles. In this work, TCH extracts containing different active ingredients were innovatively proposed as the core material of microcapsules. The feasibility of microencapsulation of multi-component TCH extracts in the essential oil state was initially demonstrated. Polyacrylate was also used as a binder to load the microcapsules onto the fabric to improve the durability and wash resistance of the treated fabric. Modeling the oil release of microcapsules for controlled release under different conditions may provide new possible uses for the materials. Results show that the constructed microcapsule has a smooth surface without depression and can be continuously released for over 30 days. The release behavior of microcapsules follows different release mechanisms and can be modulated by temperature and water molecules. The incorporation of microcapsules and polyacrylate does not significantly change the fabric's air permeability, water vapor transmission and hydrophilicity. The washing durability and friction properties of the microcapsule-based fabric are greatly improved, and it can withstand 30 washing tests and 200 friction tests. Moreover, the results of methyl thiazolyl tetrazolium (MTT) release assay using human dermal papilla cells (HDP) as an in vitro template confirm that the microcapsule has no toxic effects on human cells. Therefore, the successful microencapsulation of multi-component TCH extracts indicates their potential application in the field of TCM-loaded textiles.

Oxygen vacancies generated by Sn-doped ZrO2 promoting the synthesis of dimethyl carbonate from methanol and CO2.

Oxygen vacancy sites on a catalyst surface have been extensively studied and been proved to promote the adsorption and activation of carbon dioxide. We use Sn-doped ZrO2 to prepare a Zr/Sn catalyst rich in oxygen vacancies (OVs) by co-precipitation. The yield of dimethyl carbonate is 5 times that of ZrO2. Compared with the original ZrO2, Zr/Sn exhibits a higher specific surface area, number of acid-base sites and a lower band gap, which improves the conductivity of electrons and creates more surface. The number of reaction sites greatly enhances the adsorption and activation capacity of CO2 molecules on the catalyst surface. In situ infrared spectroscopy shows that CO2 adsorbs on oxygen vacancies to form monomethyl carbonate, and participates in the reaction as an intermediate species. This work provides new clues for the preparation of ZrO2-based catalysts rich in oxygen vacancies to directly catalyze the synthesis of dimethyl carbonate from methanol and CO2.