Plant Electrophysiology

1 Background Info
- 1.1 Electrochemistry of Plant Life
- 1.2 Related projects on this wiki
2 Protocols
- 2.1 On Measuring
- 2.2 DIY Glass Pipette Electrodes
3 Experiments on measuring potentials in algae cells
4 Past Workshops
- 4.1 Getting on Plant's Nerves @ HAIP festival, Ljubljana, Nov 2010
5 Interesting Projects

Background Info

Electrochemistry of Plant Life

Video of extracellular measurement of action potential of the venus flytrap

paper about A low-noise multi-channel device for the monitoring of systemic electrical signal propagation in plants

[https://openlibrary.org/books/OL7178438M/Response_in_the_living_and_non-living Response in the living and non-living by Jagadis Chunder Bose With illustrations Published 1902]

Related projects on this wiki

This is a subsection of all our experiments related to:

Protocols

On Measuring

Analog to Digital Converter (ADC)

Arduino

Using the arduino we can measure analog voltages using the 6 Inputs ADC. The analog voltage between 0 and 5 V is converted into a 10bit digital number, from 0 to 1023. this can be used to read a value from a sensor, eg a temperature sensor such as the TMP36, a potentiometer or from the electrodes.

Sound Card - Line In

If the potentials we want to measure are mostly changes/modulations in voltages, we can also use the analog-to-digital converter from the sound card. Although that means we cannot measure static voltages, but only fast changes changes, frequencies above ~ 1hz. The sound card is a very fast and precise ADC (single if mono, or double for stereo), sampling at 44khz or up to 96khz and 24 bit resolution.

Amplification

If the signals are to low, such as µV in the example of potentials in plants, we need to amplify the signal and make sure we do not have too much noise or other garbage in our signals. INA118 is a high end instrumental amplifier, with low noise. But maybe cheaper amp might do the trick aswell, such as the LM386

See more about Op-ampology

Multiplexing

If we want to measure more inputs we can multiplex them. meaning we measure one input at the time using a chip (4051), which got 8 inputs which are then routed to one single input on the arduino. read more about using the 4051 multiplexer/demultiplexer

Shielding

because every conducting wire, electrode or other parts of a measurement setup are also acting kinda as "antennas", its easy to pick up some artefacts, noise, humms from the electromagnetic environment. typical stuff the measure are the 50Hz humming from all the electric power and lamps or "biipbuupbiiiiip" from mobile phones. to prevent these one can use shielded cables or build a faraday cage around the whole setup.