Hi,

why cannot you place the filter paper in FTIR? Anyway, you can wash out the particles from the paper, place a drop of the suspension on the ATR crystal, and evaporate the solvent. If you cannot see the particles, increase their concentration. Use a solvent that will not damage the ATR crystal or the spectrometer.

Petr Lepcio after placing the filter paper several noice has developed in spectrum. Can you kindly share any protocol regarding sample perparation specifically on microplastic analysis via FTIR-ATR. Thank you for your kind suggestions.

I am sorry, we don't have a unified protocol for that. I usually work with samples that don't need to be filtered, I have analyzed filter cakes only a few times. If it is thick enough, you can collect it with a spoon and place it directly on the ATR crystal, but I guess this is not your case. Otherwise, you must resuspend the filtered material, usually in water, ethanol, or IPA; you can help it with an ultrasonic bath. Microparticles are visible to the naked eye, so you can directly see if you succeeded or not. Next, you need to make a sufficient concentration. You can do that by evaporating the solvent or adding more filter cakes of the same kind. Finally, shake the suspension in hand and put a droplet on the ATR crystal. Let it dry, and collect the spectrum.

Petr Lepcio Thank you so much

You are welcome. By the way, an FTIR microscope would be an interesting option to directly observe the microparticles if you can access one. For instance, we have Bruker Hyperion 3000 at our facility.

Shrayan Bhattacharjee , Sir can you succeed with this process ? My research based on this same topic. I filtered water through the 0.45 micron filter paper. But what can I do after this ? How can I retrieve microplastic from the filter paper? we don't have fluorescence microscopy. please suggest another method without this

Souparna Ghosh Exactly this the problem we are facing

Any solution sir? Can I use a normal filter paper as control ?

Sakinah Roslan Yes Dear Sakinah. It is the best. But due to availability issues sometimes we choose ATR.