　　In our project, we used a photo-bioreactor for microbial cell growth measurement. The photo-bioreactor is originally used to determine gene expression during cell growth, but we used it to measure the growth curve during continuous cultivation in BG-11 of two microalgae in our project.

The followings are the advantages of using this measurement method:

Photo-bioreactor is built from Arduino microcontroller, which is an open source software and are relatively cheap in price. Thus, the photo-bioreactor we use is generally cheaper than regular photoreactors/spectrophotometers researchers use to measure absorbance.
Compared to recording a single data every time with the use of spectrophotometer, photo-bioreactor can eliminate batch-to-batch variation after measuring several time points continuously, which significantly improves the accuracy of measurement.
Once calibrated, photo-bioreactor can automatically cultivate microalgae, measure concentration over a long period of time, and restore data back to computer automatically. Thus, it can eliminate manual measurements and saves more time for researchers.

(See more detail: Nitrogen Starvation - Experiments - Automatic Measurement)

Team:NYMU-Taipei/Measurement

Measurement