A Laboratory Experiment to Demonstrate the Principles of Sedimentation in a Centrifuge: Estimation of Radius and Settling Velocity of Bacteria
Centrifugation is a major unit operation in chemical and biotechnology industries. Here we present a simple, hands-on laboratory experiment to teach the basic principles of centrifugation and to explore the shear effects of centrifugation using bacterial cells as model particles. This experiment provides training in the use of a bench-top centrifuge, handling of bacterial cells, and data analysis. Advanced pedagogical elements in this experiment include team skills coaching and the use of electronic lab notebooks. Several cognitive conflicts presented by centrifugation data fosters critical thinking and stimulates learning by prompting students to look beyond immediately apparent conclusions.