Facile Spray-Drying Assembly of Uniform Microencapsulates with Tunable Core鈥揝hell Structures and Controlled Release Properties

详细信息    查看全文

• 作者：Wenjie Liu ; Winston Duo Wu ; Cordelia Selomulya ; Xiao Dong Chen
• 刊名：Langmuir
• 出版年：2011
• 出版时间：November 1, 2011
• 年：2011
• 卷：27
• 期：21
• 页码：12910-12915
• 全文大小：1022K
• 年卷期：v.27,no.21(November 1, 2011)
• ISSN：1520-5827

文摘

Microencapsulates with defined core鈥搒hell structures are of interest for applications, such as controlled release and encapsulation, because of the feasibility of fine-tuning individual functionalities of different parts. Here, we report a new approach for efficient and scalable production of such particles. Eudragit RS (a co-polymer of ethyl acrylate, methyl methacrylate, and a low content of methacrylic acid ester with quaternary ammonium groups) was used as the main shell component, with silica as the core component, formed upon a single-step spray-drying assembly. The method is capable of forming uniform core鈥搒hell particles from homogeneous precursors without the use of any organic solvents. Evaporation-induced self-assembly attained the phase separation among different components during drying, resulting in the core鈥搒hell spatial configuration, while precise control over particle uniformity was accomplished via a microfluidic jet spray dryer. Direct control over shell thickness can be achieved from the ratio of the core and shell ingredients in the precursors. A fluorescent compound, rhodamine B, is used as a highly water-soluble model component to investigate the controlled release properties of these microencapsulates, with the release behaviors shown to be significantly dependent upon their architectures.