Am.  Jour.  Pharni, ) 
Not.  1885.  J 
Assay  of  Ipecac. 
637 
an  exception  to  the  majority  of  alkaloids  in  this  regard.  While  dilu- 
tion of  the  fluid  is  not  without  influence  on  the  result,  this  influence 
may  be  disregarded  if  the  proportion  of  alkaloid  in  the  fluid  lies  be- 
tween 1 : 250  and  1 : 500,  and  such  is  almost  invariably  the  case  if  the 
directions  above  given  be  followed. 
The  examination  of  the  various  galenical  preparations  of  ipecac  can 
also  be  readily  made  by  Mayer's  reagent.  Solid  extracts  are  to  be  ex- 
hausted with  acidulated  water,  or,  in  case  they  contain  much  resinous 
matter,  with  acidulated  alcohol,  water  being  afterwards  added  and  the 
spirit  evaporated  ofl*;  the  aqueous  fluid  is  to  be  then  titrated  as  usual. 
The  fluid  extract  presents  no  difficulty  whatever.  Dilute  a  portion  of 
the  fluid  with  water  to  exactly  four  times  its  original  volume,  and 
take  10  cc.  of  the  mixture  for  the  assay.  Add  5  minims  of  the  6  per 
cent,  sulphuric  acid,  evaporate  on  the  water  bath  to  drive  ofl^  alcohol, 
make  up  to  a  volume  of  15  cc,  and  titrate. 
A  more  important  question,  however,  arises,  viz.,  does  the  drug  con- 
tain nothing  besides  emetine  capable  of  giving  a  precipitate  with 
Mayer's  reagent?  The  results  of  assay  by  the  method  of  Dragendorff 
indicate  the  presence  in  ipecac  root  of  from  2  to  3' 9  per  cent,  of  eme- 
tine. Those  who  have  attempted  to  extract  the  alkaloid  have  generally 
reported  a  yield  of  less  than  one  per  cent.,  but  this,  as  I  have  already 
intimated,  is  due  in  part,  at  least,  to  defective  methods  of  extraction. 
DragendorflP,  himself,  admits  that  he  was  not  able  to  extract,  by  means 
of  chloroform,  the  entire  amount  of  emetine  shown  to  be  present  by 
titration  with  Mayer's  reagent.  This  he  attributes  to  loss  of  alkaloid 
through  the  action  of  the  alkali  employed  to  set  it  free,  although  in 
some  of  his  experiments  he  used  for  this  purpose  barium  carbonate, 
and  it  seems  hardly  possible  that  this  should  exert  such  an  influence. 
By  the  use  of  Mayer's  reagent  he  found  in  the  drug  about  3*75  per 
cent,  of  alkaloid.  He  was  able,  however,  to  extract  by  chloroform 
only  2-4  to  2*9  per  cent.,  but  he  does  not  say  distinctly  that  the  same 
drug  was  employed  in  both  cases.  Others  have  had  a  similar  experi- 
ence. One  observer  only  has  reported  identical  results  by  the  two 
processes,  and  he  states  that  he  took  the  precaution  in  the  extraction 
with  chloroform  to  exclude  air  from  the  flask.  My  own  results,  in  a 
series  of  experiments  with  one  sample  of  ipecac,  seem  to  me  to  conflrm 
DragendorfT's  view,  Init  in  experimenting  with  another  sample  of  the 
drug  the  discrepancy  in  results  seemed  to  me  greater  than  could  ])os- 
sibly  be  accounted  for  by  changes  taking  place  in  the  alkaloid  during 
