Question: Has anyone experienced measuring and analyzing microplastics?

niklasjordan is asking a question about microplastics
Follow this topic

by niklasjordan | May 17, 2018 13:27 | #16361

How did you proceed, which system did you use? Somebody use the LADI trawler or are there better alternatives?

We want to determine and monitor how much microplasty is in our local lakes.

I am grateful for all the tips and experiences you share with me.


I can help with analyzing microscopic plastic particles, but not microplastics. Let's start with most expensive and go to least expensive.

For R&D, we used a liquid nitrogen cooled microscope FTIR with ATR accessory. The ATR might not be needed. It did pretty well, although black samples could give problems. Cost, with libraries, was about $100 k. It would easily handle particles smaller than 5 mm.

You might be able to get by with a standard diamond cell FTIR. These are much less expensive, but still would run in the tens of thousands of dollars. The 5 mm range particle size is something you would want to try before buying.

Polarized light microscopy is another techique. Less expensive, but it takes a fair amount of operator expertese. Don't know if it works on all plastics.

This will give you some places to start investigating. Please come back with any questions.

Thanks for your help. Its big stuff to investigating. Thanks for this ;-) Have you also some stuff to collect microplastic?

Is this a question? Click here to post it to the Questions page.

Reply to this comment...

I worked with medical devices, which is different from the microplastics you are after.

For example, if we had plastics in a liquid, I would take a dropper and a watchglass and put an ml or so of liquid in the watchglass. Hopefully, I could get at least one plastic particle to transfer the microscope FTIR for analysis.

The plastic particle needs to be analyzed in several locations. Plastics can have different polymers, or be two plastics just be stuck together. By analyzing in two or three locations, you could make sure the sample was homogenous. Or if it wasnt, you knew where it had to be cut.

For a liquid, if the above went ok, we would filter through a millipore filtration apparatus to get extra particles and compare the IRs to make sure there was no problem from the filter.

By the way, this took a lab stereo microscope with about a 6" focal length. This is a reflectance microscope, not the typical slide microscope most think of. The extra length allows the use of tools like tweezers and scalpel that might be needed to slice or move the particles to the microscope FTIR. Usually, only 40x magnification was needed.

This is a quick overview, but it gives the basic idea.

Optical microscopes aren't my strong point. There are others here that can probably help you more.

But if there is anything else you need, please let me know. Regards.

Reply to this comment...

Hi, also noting this great project; by @maxliboiron !

Reply to this comment...

Log in to comment