Crow, I could be wrong but I don't think NaCl fluoresces.
"Yeah, and that makes it even more difficlt to check an IV after it is compounded."
Yep, definitely more difficult, but not impossible. That's what they calim they are doing. They also claim that their future product which monitors the IV pump will have the capability to validate the individual components before they are mixed into the solution or validate the final IV solution prior to administering.
"I still believe that they either use a standardized mixture from which to make a signature, or check the medicines individually before they are added to the mixtire."
That's what they say, a individual signature is made for each concentration of a drug.
And I don't see why they can't do both, i.e., be able to validate the meds individually before they are mixed and test the completed solution after mixing.