CDs are now largely obsolete, thanks to the speed of the internet and the reliability and low cost of other storage media. To help keep all that plastic out of landfills, many have tried to find uses for these old records. One of the most intriguing methods of reusing DCs was recently published in Nature, which details a process for harvesting and producing flexible biosensors from them.
The process involves exposing the CD to acetone for 90 seconds to loosen the material, then transferring the reflective layer to a plastic strip. From there, various cutting tools can be used to create the correct pattern for the biosensor substrate. This has proven to be a much more cost effective method of producing this type of material compared to modern production methods, and can also be done with readily available parts and supplies.
The only downside to this method is that it was only tested on CDs that used gold as the conductive layer. Much more common aluminum discs have not been tested, but might be possible with some more research. So if you have a bunch of CD-Rs lying around, you’ll have to find something else to do with those instead.
Thanks to [shinwachi] for the tip!