RSC Advances
·
2024
·Vol. 14
·期 16
·11311-11321
·
IF 3.9
Tong Wan,Qianqian Zhang,Guocheng Jin,Shiai Xu
This work aims to determine the optimal conditions for emulsion cross-linking of chitosan (CHS) with various molecular weights using glutaraldehyde as a cross-linking agent to produce 5-fluorouracil-loaded CHS microspheres (5-FU/CHS). Their drug loading and encapsulation efficiencies are found to be in the range of 3.87–12.35% and 20.13–70.45%, respectively. The dynamic light scattering results show that 5-FU/CHS microspheres are micron-sized with a uniform size distribution, and the scanning electron microscopy results show that they are spherical. The results of thermogravimetric analysis, X-ray diffraction, and Fourier transform infrared spectroscopy demonstrate that 5-FU is successfully incorporated into the microspheres. The in vitro release tests show that 5-FU/CHS have a prolonged, pH-responsive release pattern of 5-FU, and the cumulative release rate under acidic condition is much larger than that under neutral conditions. The drug release kinetic analysis further demonstrates that the release of 5-FU can be well described by the Fickian diffusion model.
研究领域:
药剂学
·
生物材料
·
肿瘤治疗
✓ 已验证
DOI
PubMed
高影响因子
ADVANCED ENGINEERING MATERIALS
·
2025
·
IF 3.3
Dunju Wang,Yeming Huang,Jingxuan Zhang,Renhong Wang,Ruyi Miao
Aluminum/polytetrafluoroethylene (Al/PTFE) fuels are widely used in solid propellants and explosives. In this work, Al/PTFE high-energy microspheres are prepared for the first time by chitosan emulsion cross-linking. By adjusting the mass of chitosan, the properties of high-energy microspheres such as heat of reaction, flame propagation, and combustion efficiency are systematically examined. Comparison shows that high-energy microspheres with 2% chitosan content have the best overall performance. The scanning electron microscopy shows that the microsphere particles have no obvious defects on the rounded surface. Compared to physically mixed samples, the differential scanning calorimetry results show that the heat release is 13984 J g −1 (increased by 27.9%), it has the largest combustion flame area, with an ignition delay of 3.0 s (reduced by 38.8%) and a calorific value of combustion in oxygen of 17287 J g −1 (increased by 20.2%). This method can be promoted and applied to the preparation of other composite microspheres for high-energy fuels, which has a broad application prospect.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS & DESIGN
·
2022
·
IF 9.417
Wen Hou,Jiaxin Guo,Jiawei Liu,Yanan Zhao,Wenying Wei,Dan Shu,Honglian Dai
Vascularisation and mineralisation are indispensable conditions for bone repair materials. The introduction of magnesium ions into calcium phosphate-based materials can give them angiogenic and mineralising capabilities. However, the optimum calcium to magnesium ratio has yet to be determined. Microspheres have received much attention from researchers due to their flexibility, non-agglomeration and other advantages. We prepared calcium-magnesium phosphate biphasic microspheres (CMBS) using the water-in-oil emulsion cross-linking method to achieve osteogenic differentiation and vascularisation. The simultaneous use of the sacrificial template method and heat treatment endow the microspheres with a rich micro-pore structure. In addition, we investigated the compounding ratio of calcium phosphate to magnesium phosphate and determined the optimal compounding ratio (Ca/Mg = 3/1–1/1) for this material. The prepared microspheres promoted the attachment, proliferation and directed differentiation of bone marrow mesenchymal stromal cells (BMSCs) and human umbilical vein cells (HUVECs). CMBS-I (Ca/Mg = 3/1) and CMBS-II (Ca/Mg = 1/1) microspheres showed the best promotion effect among all groups. These microspheres were implanted under the skin of Sprague- Dawley (SD) rats, and the composite microspheres significantly induced vascular regeneration compared to pure phase microspheres.
研究领域:
材料科学
·
生物医学工程
·
组织工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2020
·
IF 4.192
Fan Yang,Jincheng Wang,Shiqiang Song,Pinhua Rao,Runkai Wang,Shihui Liu,Liqi Xu,Feng Zhang
A novel type of temperature and pH dual-stimuli-responsive microspheric soil conditioner was prepared for the controlled release of urea. First, poly(N-isopropylacrylamide-co-methacrylic acid) [P(NIPAM-co-MAA)] was synthesized, and the microspheric soil conditioner was prepared on the basis of chitosan-coated P(NIPAM-co-MAA) via the emulsion cross-linking method. The structure and morphology of the microsphere were characterized by Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance, polarization optical microscopy, and scanning electron microscopy. The microsphere showed controlled release behavior in different temperature and pH conditions, indicating good stimuli responsiveness. The plant experiment revealed that the microsphere can effectively promote plant growth in acidified soil and high-temperature conditions, and the pH value of acidified soil could be improved. In addition, the microsphere possessed good biodegradation property in the soil. Therefore, the multi-responsive microspheric soil conditioner owns a great potential value to amend soil conditions and promote plant growth in agriculture applications.
研究领域:
农业科学
·
土壤学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）