BME494:Materials

Spectral Analyzer: Live GFP Measurements

We used an in-house built spectral analyzer to measure GFP fluorescence of liquid E. coli cultures. A "pen light" probe was placed against the wall of a cuvette that held a sample of liquid cell culture. The pen light served as the excitation light source, and also detected emission coming back from the sample, in this case, 520 nm emission from GFP.

PROCEDURE

• E. coli (NEB10B) ells were grown overnight in selective LB liquid medium. For the class demonstration experiment, Dr. Haynes induced a Lac-repressed GFP with varying amounts of IPTG.
• 1 mL samples were transferred from large liquid cultures into tapered plastic cuvettes.
• The spectral analyzer probe was placed against the clear wall of the cuvette.
• The analyzer displayed the entire emission spectrum of the sample in real time.
• The peak height (y) at 520 nm (x) was recorded for each experimental sample, one positive control, and one negative control.

Dr. Vikram Kodibagkar is a professor in the Biomedical Engineering program who studies biological imaging. He designed and generously provided the spectral analyzer.

Fluorescence Imaging Web Cam

Details coming soon