Chromatography Forum

Hi,
I am doing my science fair project and I need to measure the amount of ethylene gas bananas produce. I have been researching and I know that a gas chromatography set can be used to measure ethylene gas but they are really expensive and too complicated for what I am doing. I was wondering if there are any easy ways to simply get a recording of the amount of ethylene gas there is in a box that contains a banana???
Please help me because If there is no easy way to measure the ethylene gas than I might have to re-think my whole assignment and I don't have much time left.
Thank you

This seems pretty ambitious. Without a gas chromatograph, you're at the mercy of measuring the "total gas produced". You also need a gas-tight vessel to contain your bananas. If a lot of gas is produced, you might be able to approximate the amount by displacement with a balloon or something to capture the pressure increase in your vessel. If the ethylene production is small, the balloon approach will not be sensitive enough.

I can see this being a very tricky exercise. You might consider choosing a different experiment.

The amount of ethylene gas produced during ripening is so small that it would be impossible to measure by simple gas volumetric measuring methods.

You would need a sensitive and selective ( other gases are also produced) approach like gas chromatography

Interestingly the identical query to yours ( word for word!!? ) was posted here in 2015

https://www.sciencebuddies.org/science- ... hp?t=14316

The suggested approach on this site using ethylene gas detector tubes would also end up being too expensive for you

As rb6banjo said, you should consider another project.

You might be able to use a biological indicator, although it would be tricky in that it's pretty binary: either the ethylene is there at a given level, or it's below. Dianthus (carnations) are more sensitive to ethylene than any other flower, from what I know, something like single-digit ppb levels to cause petal wilt.

Good paper on the subject:

http://ucanr.edu/datastoreFiles/234-950.pdf

Doing gas dilutions (with presumably ethylene-free air) to guesstimate ethylene levels is probably prohibitively difficult, however.

I wonder if there is some sort of in headspace in tube derivatization you could use to improve sensitivity. Perhaps bromination or dimethyldisulfide adducts.