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Hydro-powered DIY FTIR Spectrometer

by bryanchua | December 18, 2018 18:44 18 Dec 18:44 | #17968 | #17968


My friends and I came up with this idea in a makerspace class. Does anyone know if such an idea would work and what materials would be needed? The end goal is to make something that could detect for chemical pollutants like mercury and microbiological contaminants like E. coli. It would be deployed in rural areas with little or no WiFi or cellular networks and the LoRaWAN chip will transmit water quality data reliably and anonymously so people on the ground would not be persecuted by illegal gold mining or drug syndicates who pollute their water. The hydro-powered motor powers the floating device and recharges the battery to power the Fourier-Transform Infrared (FTIR) spectroscopy module that will periodically measure the water.


I like the idea. But why are you selecting ftir?

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I've never seen FTIR used for mercury detrmination. Usually, that is a variation of AA.

The instrument set up you show is for transmission. Probably, reflectance would be needed instead. Either MIR or ATR. That leads to a different situation. Then, how do you ID a specific microbe by FTIR? The common instruments can't do that. Is there a reference you have? Or a different technique?

Please keep investigating and good luck.

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Thanks for the feedback @Ag8n !

We used FTIR because we saw that people have made DIY FTIR spectrometers and we also read these articles where FTIR was used for mercury detection and E. coli detection respectively:

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Just realize, these methods are far from being implemented. The mercury one is " proof of concept", which means it still needs troubleshot, validated, etc. to be a standard method. It also uses a mix of methods. SPE( solid phase extraction ) either takes a robot or a person to do. The work and can be touchy, depending on the test done. Usually, the sample is spiked and recovery calculated.

The e. Coli method is based on a detector that is liquid nitrogen cooled. Not your run of the mill instrument. They tend to be much more expensive than a homemade type ftir.

Keep up the research!

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