im not sure that titration would work... given that if you titrate the acid into the freebase.. you would form the salt.... and viceversa.... honestly ive never used titration to determine concentration of such a compound... and im not sure that it is possible... however given that im wrong remember the tiny volumes we're talking about...practically it would be too hard and not accurate.... not in my opinion anyway... but then im not a very good chemist
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seperation of the pills contents via anything but hplc would also not be practical for determining pill quality for the following reason.
matter cannot be created or destroyed... except in fission reactions and column chomatography. in my experience no matter how much solvent you put on you never get back everything from silica colums... but again.. im not the worlds greatest chemist
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again i dont believe this method is practical for determining accurately determining mass of mdma... nice for prification though if you can be bothered... and have the gear...
my best advice is to examine it via TLC... that will give you an idea of the number of compounds present.. im sure you can find rf values for given compounds with given solvents with given plates... wont give you masses.. but its a suprisingly sensitive technique ..