Thank you for reading! Let me know if there's anything I can help clarify

I have access to the paper you're talking about--here is a snippet of the section you may be most interested in:

Let me check if I'm allowed to download the whole paper and share it with you.

I don't know of a community science project using the pigment extraction method since there are some specialized steps and equipment, but we're curious to see if you or anyone has ideas for a more DIY-able version!

Still have to do more work. But the acetone extract seems like something that might be doable in a home lab type situation. The acetone extract is where I'm going. Nail polish remover is something like 70% acetone. And no bad extraction conditions are required. Magnesium carbonate is available in the over the counter section of most pharmacies. The public lab spectrometer should be able to cover the narrow range needed (say 425 nm area) without much problem. The question is the centrifuge.

One word of warning. Solvents ( like acetone) and plastic cuvettes do not usually go together. The worst case is the plastic melts, but the plastic will also smear, which also makes the cuvette unusable. So the other choices are glass of quartz. Quartz is the better choice, since it is good through the entire Uv/vis, but you will usually pay for the honor. Glass should go below 400 nm without any problems, but double check the vendor specks to be sure.

Ok. Trying to stay as close to duplicate the original paper as closely as possible. R.la cera isn't in this area. But other closely related lichen supposedly do. First shot is the Fruticose lichens. No one knows of any close by, but have a lot more work to do on that road. Found an interesting video on YouTube "Using lichens to determine air quality" by the naturalist. As for method development. Looking for possible alternatives to the centrifuge. Possibly, disposable hplc filters. Need some help here. Why are the lichen stored in the dark during the extraction?

Was checking one of the online vendors. Found new centrifuges for $70. Industrial quality centrifuge costs were much higher, but who knows. If you are interested in making a hand powered centrifuge, try BioRxiv. The article is titled "A 3D printed hand powered centrifuge for molecular biology". It will handle up to about 2 ml of sample. And for a review of this type of centrifuge see YouTube "Recreating Paperfuge: The hand powered centrifuge" by Qosmos Chen. With a normal cuvette, at least 2 ml is needed. Even then, the cuvette will not be full.

As for the mortar and pestle, there are many options. Some mortar and pestles are very expensive, but they don't have to be. They should be easy to clean and non porous. And the pestle should be easy to grasp. Usually , we would raid the stopper drawer for a single hole stopper. Then, the stopper would go over the top of the pestle. It made it easier for some of the common grinding operations that go on in the lab.

Another, more current option , is to use a coffee grinder. With the temperature issues this material shows, probably using the frozen state would be good, if possible. Throw the samples in the freezer the night before, then prep them in the coffee grinder. Make sure the minimum amount of time necessary is used. Don't know if it would work. But it sure would save time.

A test of this method might be to use lawn clippings and run it through the procedure. The idea is to extract chlorophyll, which should be present in lawn clippings ( although probably a different kind of chlorophyll). Will be writing up a draft test method over the next few days.

If you are using the public lab spectrometer, a light source for around 400 nm is needed. It looks like there are some blue or violet led bulbs/ flashlights that cover this range. Might be a good place to start. The other option is the lines in the 660 nm range. Which should also be doable with leds.

There are 3 in 1 flashlights ( blue, white, and red) that would be good for this application- as long as the color was more like purple instead of blue. The flashlight would be able to switch between the ends of the spectrum, for each individual anaysis, as well as an overall scan. Blue is something like 445 nm to 490 nm. The area of chlorophyll peaks needs is more like 415 nm to 435 nm. ( if you down the standard ROYGBIV, this is indigo or violet). Also looking for light bulbs filling this requirement. There are a few. Will keep looking.

Looking into the 660 nm lines. It's not that LEDs don't exist for 425 nm region. They do. But the ones in the catalogs seemed expensive. Going down the 660 nm road, now.

Best bet- use an old fashioned tungsten lamp. Not a LED claiming to be a tungsten lamp. An LED has a narrow bandwidth. An old fashioned tungsten lamp should have a good bandwidth at the low end of the visible spectrum. Many tungsten lamps are still listed outside of the non-standard sizes.

The tungsten lamp remarks only apply to the 660 nm red lines.

There's some work needed to modify this research protocol so it can be done in regions like Ohio that might not have the exact species listed in the paper. A good place to start is this US Forest Service table that indicates lichen sensitivity to certain pollutants, and you can use it to get a sense of what lichens are most common in the region and how much they are impacted by pollutants