Fundamental studies of adhesion phenomena involving vesicles

点击翻译按钮获取中文摘要

Vesicles are micron or nanometer-sized particles which compartmentalize a finite volume of liquid with the help of a bounding membrane. Vesicle-based products such as fabric softeners, skin creams, hair lotions, and therapeutics such as Doxil (chemotherapeutic) and Amphotericin (antifungal) together constitute a multi-billion dollar business worldwide. However, due to the trial-and-error, experimentally-focused nature of development of many of these products, a fundamental understanding of what factors would lead to lesser raw material consumption, more efficient resource usage, lower environmental impact and better product function is still lacking. This project represents a first step towards the development of a systematic understanding of the above relationships. In particular, we focus on one phenomenon that governs optimization of vesicle-based products - vesicle adhesion (i.e. vesicle sticking). Vesicle adhesion is a crucial step in the function of products such as lotions and therapeutics; on the other hand, it is a menace for products such as fabric softeners, and leads to creaming or settling of the active material in these products. In this project, we will develop two tools that will characterize vesicle adhesion phenomena. One is a flow device called the microfluidic four-roll mill, which will help us understand how flow induces or prevents the adhesion of vesicles. The other device is a force apparatus, which determines how strongly or weakly a vesicle binds to a surface or another vesicle. The theoretical component of this project will formulate models and simulations that will predict the conditions which enhance or prevent vesicle adhesion. The tools and results from this project will impact a wide variety of fields other than vesicle-product industries. The interactions between biological cells and surfaces with and without flow have implications in blood flow, immunological response mechanisms, intra and intercellular transport, drug delivery and tissue engineering. Our tools will also be applicable for designing emulsion systems which are prevalent in the food, vegetable oil and petroleum industries, all billion dollar industries in Canada.