Preparation of microcapsules containing fine antimicrobial particles by sol-gel process in reverse suspension

反悬浮溶胶-凝胶法制备抗菌微粒微胶囊

• 批准号: 12650748
• 负责人: KIMURA Isao
• 金额: $ 1.54万
• 依托单位: Niigata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650748/
• 关键词: sol-gel process; silver chloride; silica; tetraethoxysilane; suspension; microcapsule; colon bacillus; antimicrobial material; ゾルーゲル法; 銀スルファト錯体; 構造制御; 逆相懸濁系

When silver thiosulfato complex was used as antimicrobial material, dispersing-type microcapsule was not obtained because of the segregation of the complex onto the capsule surface. The complex content inside the microcapsule was somewhat improved by using dispersion stabilizer. However, the complex was released very fast, when the microcapsules were suspended in water. It was found that they were not suitable for the use as antimicrobial materials to be served for a long term.Thus, fine AgCl particles were used instead of silver thiosulfato complex. Polyvinylalcohol (PVA) of a nonionic surfactant was the most effective as a dispersion stabilizer, resulting in microcapsule in which AgCl was uniformly dispersed. The Use of anionic or cationic surfactant did not form stable dispersion. The AgCl content of the microcapsule and the amount of AgCl released to water increased with the increase in the dispersion stabilizer concentration. The release rate decreased with the dispersion stabilizer concentration to about 6% for 48 h.These microcapsules were changed to gray in color during the ordinary handling. This is due to decomposition of AgCl by UV irradiation. By hybridizing the microcapsules with titania from TTIP, they were kept white in color. This is suggested that titania is effective for shielding from UV irradiation and hiding the inside of the microcapsule. The addition of TTIP of 20 - 50 mol/m^3 to the continuous phase resulted in good composites.The antimicrobial effect of the microcapsule was confirmed by cultivating a colon bacillus (Escherichia coli) in suspension of the microcapsules.

当使用硫代硫酸银络合物作为抗菌材料时，由于络合物偏析到胶囊表面，未能获得分散型微胶囊。通过使用分散稳定剂，微胶囊内的络合物含量有所提高。然而，当微胶囊悬浮在水中时，复合物释放得非常快。结果发现它们不适合用作长期使用的抗菌材料。因此，使用细AgCl颗粒代替硫代硫酸银络合物。非离子表面活性剂聚乙烯醇 (PVA) 作为分散稳定剂最有效，可形成 AgCl 均匀分散在其中的微胶囊。使用阴离子或阳离子表面活性剂不能形成稳定的分散体。随着分散稳定剂浓度的增加，微胶囊的AgCl含量和释放到水中的AgCl量增加。 48小时内，释放率随分散稳定剂浓度下降至约6%。在普通处理过程中，这些微胶囊颜色变为灰色。这是由于紫外线照射下 AgCl 的分解造成的。通过将微胶囊与 TTIP 的二氧化钛杂交，它们保持白色。这表明二氧​​化钛对于屏蔽紫外线照射和隐藏微胶囊内部是有效的。在连续相中添加 20 - 50 mol/m^3 的 TTIP 可获得良好的复合材料。通过在微胶囊悬浮液中培养结肠杆菌（大肠杆菌）证实了微胶囊的抗菌效果。