FagNewton
I was aware of the urea, and I'm getting a condescending vibe from you, but I'll continue. Is there a way to fool the strips? What I'm getting at is this:
As I've been told, the usual strip functions by reacting to water and the chemicals found in the usual drugs. If one were to make a fake urine, who could possibly tell the difference, so is it possible?
If you were to make human urine yes but it's impossible to do so with a chemistry set if that's what your getting at.
Hold on I will quickly read up on how they do such drug tests.
They use an immunoassay. Which means they take a sample of the piss, and they add Antibodies that bind with Drug metabolites, Urine, Uric acid or Human Serum. They may also test these days for unnatural chemicals which can be added afterwards to break down or alter said chemicals to check for adulteration.
They would expect a positive result from the human Serum result before they test for the drug metabolites If they get a negative on that test they know there not dealing with human urine and will automatically fail that result. Or least declare the sample invalid.
Human Serum cannot be gotten from anywhere other than human fluids although you can fractionate it out of human blood You can't really mix up a batch of synthetic urine in the way you seem to imply.