| 1 | Preparation, characterization, antimicrobial and cytotoxicity studies of copper/zincloaded montmorillonite显示文摘Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction(XRD), fourier transformed infrared spectroscopy(FTIR) and transmission electron microscopy(TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results: In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria(Escherichia coli), gram-positive bacteria(Staphylococcus aureus), fungi(Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions: The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry. | Lefei Jiao Fanghui Lin Shuting Cao Chunchun Wang Huan Wu Miaoan Shu Caihong Hu | 2017 | Journal of Animal Science and Biotechnology2017，8，3： | 4 |
| 2 | The complexation of insulin with sodium N-[8-(2-hydroxybenzoyl)amino]-caprylate for enhanced oral delivery:Effects of concentration, ratio, and pH显示文摘Permeation enhancers(PEs),such as N-[8-(2-hydroxybenzoyl)amino]-caprylate(SNAC),have been reported to improve the oral absorption of various macromolecules.However,the bioavailabilities of these formulations are quite low and variable due to the influences of enzymes,pH and other gastrointestinal barriers.In this study,we revealed that SNAC could interact with insulin to form tight complexes in a specific concentration(insulin≥ 40μg/mL)-,ratio(SNAC/insulin≥ 20:1)-and pH(≥ 6.8)-dependent manner,thus contributing to a significantly high efficacy of oral insulin delivery.Specifically,absorption mechanism studies revealed that the SNAC/insulin complexes were internalized into the cells by passive diffusion and remained intact when transported in the cytosol.Furthermore,the complexes accelerated the exocytosis of insulin to the basolateral side,thereby enhancing its intestinal mucosal permeability.Eudragit;S100-entrapped SNAC/insulin microspheres were then prepared and exhibited an apparent permeability coefficient(P;) that was 6,6-fold higher than that of the insulin solution.In diabetic rats,hypoglycemic activity was sustained for more than 10 h after the microspheres were loaded into entericcoated capsules.Further pharmacokinetic studies revealed an approximately 6.3% oral bioavailability in both the fasted and fed states,indicating a negligible food effect.Collectively,this study provides insight into the interaction between PEs and payloads and presents an SNAC-based oral insulin delivery system that has high oral bioavailability and patient-friendly medication guidance. | Huixian Weng Lefei Hu Lei Hu Yihan Zhou Aohua Wang Ning Wang Wenzhe Li Chunliu Zhu Shiyan Guo Miaorong Yu Yong Gan | 2022 | Chinese Chemical Letters2022，33，4： | 0 |
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