Am.  Jour.  Phfirm  ) 
Nov.,  1885.  I 
Assay  of  Ipecac. 
535 
ipecacuanha,  that  of  Zinoffsky,  recommended  by  Dragendorff  (Werth- 
bestimmimg  einiger  starkwirkender  Droguen)  is  the  only  one  worthy  of 
consideration.  Dragendorff  directs  to  mix  the  finely  powdered  drug 
with  five  times  its  weight  of  water  containing  sulphuric  acid  [one 
minim  of  a  dilute  acid  1 : 8,  for  each  grain  of  drug],  allow  to  macerate 
twenty-four  hours,  add  alcohol,  equal  in  weight  to  the  water  used,  and 
continue  the  digestion  48  hours.  An  aliquot  portion  of  the  fluid  is 
then  to  be  evaporated  to  drive  off  the  spirit,  and  the  residue  diluted 
with  water,  filtered  and  titrated  with  Mayer's  reagent,  of  which  1  cc. 
precipitates  0*0189  gm.  emetine. 
The  process  is  very  easy  of  execution,  and  has  in  its  favor  the  cir- 
cumstance that  it  shows  a  larger  proportion  of  alkaloid  than  any  other 
assay  process. 
The  time  of  the  assay  may  be  somewhat  shortened,  if  the  drug  is 
employed  in  a  very  fine  powder,  by  allowing  the  maceration  to  go  on 
at  a  temperature  of  50°C.  (1 22°,F.)  and  shaking  the  mixture  frequently. 
It  is  not,  however,  easy  to  reduce  the  root  to  an  impalpable  powder, 
and  it  is  better,  when  there  is  no  haste,  to  extend  the  time  of  macera- 
tion to  three  or  four  days.  The  details  of  the  process,  as  I  am  in  the 
habit  of  using  it,  are  as  follows  : 
Place  in  a  suitable  bottle  or  flask  50  cc.  of  distilled  water  (without 
addition  of  acid),  afterwards  put  in  ten  grams  of  ipecacuanha  in  fine 
powder ;  mix,  cork  the  bottle  or  flask,  and  set  by  in  a  warm  place, 
shaking  occasionally.  At  the  end  of  twenty-four  hours  add  to  the 
mixture  52  cc.  of  alcohol,  making  a  total  of  100  cc.  of  menstruum 
owing  to  condensation  of  volume ;  cork,  and  set  aside  again  for  three 
days,  shaking  well  several  times  a  day.  Then  measure  out  with  a 
pipette  for  the  assay  25  cc.  of  the  clear  fluid,  which  will  represent  as 
nearly  as  possible  2J  grams  of  drug.  Put  this  in  a  capsule,  add  5 
drops  of  a  highly  dilute  sulphuric  acid  (containing  6  per  cent.  H2  SO4), 
evaporate  at  a  gentle  heat  until  all  the  alcohol  is  driven  off",  add  water 
to  make  up  to  the  original  measure  of  25  cc,  digest  a  few  minutes  on 
the  water  bath,  allow  the  mixture  to  cool,  and  proceed,  without  filter- 
ing, to  titrate  with  Mayer's  reagent.  [Filtration  appears  to  involve 
a  needless  expenditure  of  time,  observation  showing  that  it  does  not 
aflect  the  result.] 
The  solution  employed  for  the  titration  may  conveniently  be  made 
of  one-half  the  strength  of  Mayer's  reagent.  One  litre  will  contain 
therefore  6'773  grams  corrosive  sublimate  and  25'  grams  potassium 
