pinkish color and then became dark brownish after processing indicating epinephrine instability the seventh sample water 0 1 mm sodium metabisulfite 0 1 m perchloric acid discolored to a slightly pinkish color 0 1 mm sodium metabisulfite 0 1 m perchloric acid usually provided optimum stability for epinephrine for several months the ft ir spectrum for epinephrine base before fig2 b is different from the ft ir spectrum after processing fig2 a which reflects the degradation that occurs during processing the epinephrine base required stabilization with acetic acid or phosphoric acid in the suspension media and cooling of the reaction chamber to minimize degradation the first sample a suspension of 7 0 mg ml was used as a stock suspension and was used to prepare the other dilutions thus the passes are additive and each pass represents an additional pass to the previous dilution after ten passes in the last run includes samples one two three and the first pass of sample 4 the particle size distribution psd did not change no effect after ten passes according to nicomp readings the fourth sample was processed six times 6 passes in one step followed by an additional ten passes for a total of sixteen passes continuously the epinephrine bitartrate salt form of epinephrine was more stable than the epinephrine base did not show any discoloration and tolerated the fabrication conditions nanomilling the particle size distribution psd of epinephrine bitartrate after processing fabrication using zetasizer was 5000 nm 60 and 500 1000 nm 30 40 the yield of fabricated epinephrine bitartrate after drying was 68 the fourier transformation infrared.