Design, Fabrication and Testing of an Electrically Controlled Microfluidic Capillary Microvalve Based on Hydrophobicity

• Main Author: Kulkarni, Gitesh S
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2019
• Subjects: Biomedical engineering; Engineering
• ISBN: 1392421918; 9781392421918

Microfluidics is a promising disciple that combines "micro" amount of fluid handling in "micro" sized channels and has found applications in diverse fields such as biotechnology and environmental monitoring. Combination of microfluidics with digital electronics technology has spurred creation of Lab-on-a-Chip (LOC) devices that are field-deployable and bought to market in the last few decades. In these devices, positioning/transportation of liquids has remained a critical issue. A sample of fluid needs to be acquired from a specimen reservoir and moved to a different reservoir location for analysis. Inexpensive, reliable and straightforward methods to do this transportation makes such instruments low-cost and robust for use in the field for a variety of purposes. Current ways to do fluid movement require high electric field and hence requiring the use of high voltages (thousands of volts), making the device bulkier. Another approach to use a pneumatic pump for droplet movement is also detrimental in making LoC devices portable due to sizes of associated electronics and electrical parts. This thesis presents the design of a microfluidic valve using capillary action, hydrophobicity, and low voltages (several volts). The use of low voltages brings the "micro" realm to the digital electronics part of LOC. It could lead to better portability, low-power operation of LOC devices, and consequently more adoption in field applications. The design process is based on practical considerations found during experimentation. This method was tested, and results are presented for various biochemical mediums, including KCl, PBS, GMOPS, Cell culture and FBS.