Comment by 0cVlTeIATBs

Following the rabbit hole leads to this wiki[0] which points to this "homebrew source"[1] which says, under Laboratory equipment -> Learn more:

"Although it is theoretically possible to make a 'low-cost' production (using only a 5mL syringe, a spinning top filter, a kitchen scale and a pressure cooker), the reproducibility and the quality will not be desired."

[0] https://diyhrt.wiki [1] https://oelabs.co/en