Is Froehde reagent reliable?
This version has been translated from Polish and links to the relevant test kits have been added. In a life-threatening situation call 112. This article is informational and serves harm reduction. It does not encourage the use of psychoactive substances and does not replace medical advice.
Froehde is reliable, and honestly positioned as a confirmatory reagent rather than a primary one. Froehde is molybdic acid in sulfuric acid, and for most of what people test it produces a result that agrees with marquis or mecke rather than adding a new fact. That is not useless, because agreement between independent reagents is what a presumptive identification is made of, but it does mean froehde is the fourth or fifth bottle to buy rather than the first.
Where it does add something
Opioids, where it separates several compounds that marquis groups together, and the 2C family, where its reaction is distinct enough to be worth having alongside mecke. It is also useful on samples that gave an ambiguous marquis result, because a second acid-based reagent with different selectivity either supports the reading or does not.
Froehde reagent, 7.30 EUR · Froehde instructions
Where it does not
Cathinones, again, and anything where you need to distinguish a primary from a secondary amine, which is simon's and robadope work. On a pressed pill froehde will mostly tell you what marquis already told you.
Simon's or Robadope · Full reagent kit, 11 reagents
Questions?
Do I need froehde if I have marquis?
Not to begin with. It becomes useful once you want a second opinion on ambiguous results or you are testing opioids.
Is it the same as mecke?
No. Both are acid-based but they use different metal salts and have different selectivity, which is what makes the pair informative.
Why is my froehde result the same as my marquis result?
That is common and it is the point. Agreement between reagents is evidence.