532 
Assay  of  Ipecac. 
(  Am.  Jour.  Phaim. 
I      Nov.,  1885. 
such  considerations  as  these,  and  although  in  its  letter  it  applies  only 
to  the  crude  drug,  it  is  fair  to  assume  that  its  spirit  may  cover  an  in- 
quiry into  the  method  of  assaying  the  galenical  preparations  of  ipecac. 
Crude  ipecac  may  be  assayed  in  various  ways  according  to  the  object 
proposed  in  the  investigation.  We  may  desire  to  know  simply  what 
is  the  medicinal  activity  of  the  root  in  its  crude  state,  either  expecting 
to  employ  it  in  the  form  of  a  powder  to  be  given  in  substance,  or  de- 
siring to  know  how  to  adjust  the  doses  of  the  various  preparations  of 
the  drug.  Or  we  may  wish  to  ascertain  how  much  alkaloid  we  can 
extract  from  the  root  by  a  given  process ;  our  assay  process  in  such  a 
case  would  not  seek  to  exhaust  the  drug,  but  rather  to  imitate  on  a 
small  scale  the  extraction  process  adopted  in  the  actual  manufacture. 
Before  entering  upon  a  study  of  these  several  assay  processes,  it  may 
be  advantageous  to  review  the  methods  that  have  been  proposed  for 
extracting  emetine  from  the  drug. 
The  process  of  MM.  Pelletier  and  Dumas  ("Ann.  Ch.  Phys.  [2]  xxiv, 
180")  is  that  given  in  most  of  the  text  books.  It  is  given  in  Watts^ 
Dictionary  of  Chemistry  as  follows :  The  powder  of  ipecacuanha  is 
digested  in  water  with  calcined  magnesia;  the  deposit  is  thrown  on  a 
filter,  washed  carefully  with  very  cold  water  and  dried,  and  the  eme- 
tine is  then  taken  up  by  alcohol.  It  may  then  be  combined  with  an 
acid,  and  the  salt  may  be  purified  with  animal  charcoal."  The  yield 
is  not  stated.  The  method  is  one  I  have  never  tried,  partly  because  I 
hesitated  about  exj)osing  the  alkaloid  to  the  action  of  magnesia  during 
the  drying  process,  and  partly  because  experience  with  other  alkaloids 
does  not  favor  the  use  of  an  aqueous  menstruum  in  the  primary  ex- 
traction. 
A  process  quite  similar  to  this  one  in  principle  was  recommended  in 
1875  by  Glenard  ("Journ.  de  Pharm.  et  Chim.Sept.  1875"),  but  ether 
is  employed  as  the  solvent  in  place  of  alcohol — an  obvious  improve- 
ment, and  lime  is  substituted  for  the  magnesia.  The  process  "consists 
in  treating  with  ether  a  suitably  })repared  powder,  or  an  extract  of 
ipecacuanha  and  lime,  or  the  precipitate  formed  upon  adding  an  excess 
of  lime  to  a  solution  obtained  by  treating  ipecacuanha  in  the  cold  with 
water  acidulated  with  sulphuric  acid.  Either  of  these  mixtures,  or 
the  precipitate  when  treated  with  ether  will  yield  all  the  alkaloid  it 
contains."  The  alkaloid  is  removed  from  the  ethereal  solution  by 
shaking  with  acidulated  water,  and  may  then  be  precipitated  by  the 
addition  of  ammonia.    From  this  precipitate  crystallizable  salts  may 
