A laser-based micro-rheology instrument has been developed for non-invasive screening of evolved bacteria for exopolysaccharides (EPS) production. This new capability enables us to rapidly screen for changes in texture, avoiding lengthy traditional rheology testing procedures.
Rapid screening consists of loading samples into a standard well plate and placing the plate inside the instrument as shown in the image. A Microsoft Windows application defines the plate size, contents and various experimental parameters. Full 3D (x-y-z) motion delivers each sample to the laser's measurement location. Capturing data from a 96 well plate takes 3-4 minutes, and the entire plate is re-measured every 10-15 minutes over several hours. Temperature is controlled using a simple enclosure.