140 
THE ASSAY OE IPECACUANHA. 
BY PROFESSOR ATTFIELD, PH.D., 
DIRECTOR OF THE LABORATORIES OF THE PHARMACEUTICAL SOCIETY OF GREAT BRITAIN. 
A few months ago a specimen of ipecacuanha was sent to me for assay by 
Messrs. C. G-. Meier and Co., merchants, of London. It was a portion of six 
cases, about 700 ]bs., received from Bogota, the capital of New Granada. 
The appearance of the sample enabled me at once to state that the article 
was not true ipecacuanha (Cephaelis Ipecacuanha), but a variety known as 
striated ipecacuanha,—the roots of Psychotria emetica, the pieces being 
“ neither annulated nor undulated, but longitudinally striated.” Whereas, 
however, striated ipecacuanha is commonly somewhat soft, but pulverulent 
and more or less brittle, the specimen under examination was soft and elastic, 
like gutta-percha. 
Striated ipecacuanha was analysed in 1820, by Pelletier, who found it to 
contain 9 per cent, of emetina, the active emetic principle. The same che¬ 
mist obtained 16 per cent of emetina from true ipecacuanha. The process he 
adopted was as follows :—Make a tincture of the weighed ipecacuanha (one 
of root, in 3 parts English rectified spirit, and 2 water), evaporate to dryness, 
dissolve residue in water, and, after filtering the liquid through magnesia (to 
saturate acids and liberate combined emetina), again evaporate to dryness ; 
weigh the residue. This process has answered very well in my hands tor the 
assay of all ordinary samples of ipecacuanha—true or false—giving apparently 
a tolerably pure product; but applied to the sample under consideration, it 
furnished no less than 56^ per cent, of what evidently was not pure or even 
slightly impure emetina. This result led to a detailed examination of the 
article, the end of which was, that in the place of starch usually largely pre¬ 
sent in both true and striated ipecacuanha, and of which no trace was found, 
there occurred 5‘4 per cent, of grape-sugar, and 34 per cent, of cane-sugar (or 
a substance soluble in water, and convertible in grape-sugar by ebullition 
with acids). In Pelletier’s process of analysis this saccharoid matter would 
necessarily accompany whatever emetina might be present, and, if not 
noticed, be reported by an analyst as emetina itself. So far as known, how¬ 
ever, more than a mere trace of sugar has not, until now, been noticed. 
It next became necessary to devise a process for the estimation of emetina, 
which should not be liable to error on account of the presence of sugar. This 
was found to be impracticable by the ordinary principle of separation by sol¬ 
vents. The old process was therefore simply supplemented by the quantita¬ 
tive estimation of the nitrogen in the evaporated aqueous solution of the alco¬ 
holic extract of the ipecacuanha ; the absence of albuminoid or other nitro¬ 
genous matter than emetina was thereby insured, while all non-nitrogenous^ 
matter was excluded. Instead, therefore, of weighing the final product of 
Pelletier’s process, above given, a weighed portion of it is mixed with soda-lime 
and burnt in the usual manner ; and from the amount of nitrogen produced, 
the proportion of emetina calculated, the known percentage of nitrogen in the 
pure alkaloid (4'3) being the only important datum to be remembered. 
Working by this process, a sample of true ipecacuanha, from the museum 
of the Pharmaceutical Society, yielded 17 per cent, of impure (Pelletier’s) 
emetina, but only 10^ of pure emetina; while a specimen of striated ipeca¬ 
cuanha, from the same source, gave 10£ of extract, containing pure emetina, 
equal to 6^ per cent, of the root. The striated ipecacuanha, sent by Messrs. 
Meier, affording, it will be recollected, 56^ per cent, of what has hitherto 
been regarded as emetina, but which should be termed ‘ saccharoid extract,’ 
