Confined biofilm culture and flow in microfluidic channel

• Main Author: Lim, Chun Ping
• Other Authors: Lam Yee Cheong
• Format: Theses and Dissertations
• Language: English
• Published: 2015
• Subjects: DRNTU::Engineering::Mechanical engineering::Fluid mechanics; DRNTU::Science::Biological sciences::Microbiology::Bacteria
• Online Access: http://hdl.handle.net/10356/65306
• Institution: Nanyang Technological University

A biofilm is an aggregate of bacteria held together by an extracellular polymeric matrix on an interface. A biofilm residing on a liquid-solid interface is significantly influenced by the hydrodynamic environment. Although various microfluidic flow cells have been developed to study biofilms under well-defined flow conditions, the control of biofilm growth remains a challenge. Nutrient zoning was developed to achieve biofilm growth confinement and was demonstrated in two microfluidic flow cells, namely a T-shaped flow cell (T flow cell) and a multiplexed flow cell, using two-phase immiscible fluid flow. Complete confinement of biofilm growth was achieved which provided a reference surface free of biofilm in the same channel to facilitate post-experiment analysis. Microfluidics generally operates in the laminar flow regime. However, chaotic and turbulent flows can have significant effects on the structure and function of biofilms. Thus, a platform for generating viscoelastic chaotic flow in micro-channels was developed. Chaotic flows of polymer solutions were generated in an H-shaped micro-channel (H-micro-channel) and the mechanisms of their generation were studied. Furthermore, characteristic and maps of the chaotic flows were constructed which can be employed to generate a defined chaotic flow to study biofilm systematically.