Simplifying the challenge of algal culture growth monitoring

Monitoring algal growth in test tubes without affecting algal cultures is a challenge for researchers. Turner Designs recently demonstrated an excellent solution to this concern using two of their standard products, the C-Fluor chlorophyll probe with their in-line adaptor.

Multiple algal cultures were diluted to low concentrations of chlorophyll. Cultures were evenly distributed into 25 mm diameter glass test tubes and placed in a room temp environment near a window for exposure to natural light. Growth was monitored using Turner Designs’ C-Fluor chlorophyll probe with the C-Fluor in-line adaptor. Daily measurements were made and test tubes were returned to their original location near the window for continued natural light exposure. These measurements were repeated until each C-Fluor probe’s response saturated.

C-Fluor probes output a voltage response proportional to the fluorescence detected. The C-Fluor in vivo Chlorophyll Blue Excitation probe was used to measure the algal test tube cultures for this growth monitoring project. Turner Designs’ Databank handheld data logger was used to display voltage. Maximum concentrations detected ranged from 90 to 183 µg/L and are plotted for five of the twelve cultures monitored.

Growth data can help determine ideal conditions for growth, calculate growth rates, or monitor densities for feeding experiments. Other sensors from our C-Fluor product line can also be used to monitor for pigments such as phycocyanin or phycoerythrin which may indicate contamination of algal cultures.

C-Fluor are sensitive, extremely low power single wavelength in situ fluorescence and turbidity probes available in several optical configurations. Factory-calibrated, each C-Fluor ships with a calibration certificate used to convert the analogue or digital output signal to a specific concentration estimate. In addition to in vivo chlorophyll, phycocyanin and phycoerythrin, C-Fluor probes are also available for detecting: crude oil, CDOM/fDOM (dissolved organic material), fluorescein dye, rhodamine dye, optical brighteners and turbidity.