276 
Emetine  Hydrochloride. 
Am.  Tour.  Pharm. 
May,  1919- 
determined  quantitatively,  in  order  to  ascertain  if  the  proportion 
present  was  material  in  quantity. 
The  method  employed  was  based  on  the  U.  S.  P.  qualitative  test 
for  cephaeline  modified  by  starting  with  0.6  Gms.  of  the  emetine 
hydrochloride,  increasing  all  reagents  six  times  when  necessary, 
weighing  the  cephaeline  instead  of  treating  it  with  sulphuric-molybic 
acid  and  running  a  blank  correction  throughout  the  method.  The 
larger  quantity  of  emetine  hydrochloride  was  employed  in  order  to 
obtain  an  accurately  weighable  quantity  of  cephaeline. 
The  quantitative  method  can  be  described  as  follows : 
Dissolve  0.6  Gm.  in  30  mils  of  distilled  water  in  a  separatory 
funnel,  add  to  the  solution  18  mils  of  sodium  hydroxide  T.  S.  and 
shake  it  out  with  60-mil  portions  of  ether  until  the  residue  obtained 
by  evaporating  1  mil  of  the  ethereal  liquid,  when  dissolved  in  1  drop 
"of  diluted  hydrochloric  acid  and  1  mil  of  distilled  water,  no  longer 
yields  a  turbidity  with  iodine  T.  S.  Now  acidulate  the  aqueous  liquid 
with  diluted  sulphuric  acid,  then  add  ammonia  water  until  alkaline 
and  shake  it  out  with  60  mils  of  ether.  Separate  and  evapoate  this 
ethereal  liquid  in  a  tared  flask.  Dry  the  residue  of  cephaeline  in 
the  flask  at  6o°  C.  to  constant  weight  and  weigh  it  as  anhydrous 
cephaeline  alkaloid.  Run  a  blank  correction  throughout  the  method 
and  correct  final  weight  of  anhydrous  cephaeline  alkaloid  accord- 
ingly, if  necessary. 
Five  extractions  with  ether  are  usually  required  before  the  iodine 
T.  S.  fails  to  yield  a  turbidity  with  the  extraction,  and  even  after  a 
sixth  extraction,  a  slight  turbidity  is- sometimes  obtained.  The  use 
of  five  extractions  was  adopted  in  these  experiments.  A  blank  cor- 
rection indicated  a  necessary  deduction  of  from  Yi  to  1  milligram 
from  the  weight  of  anhydrous  cephaeline  alkaloid  obtained  in  the 
several  tests. 
The  quantitative  test  was  applied  to  samples  of  emetine  hydro- 
chloride representing  the  products  of  five  American  manufacturers 
with  the  following  results : 
Anhydrous  Cephaeline  Alkaloid. 
Manufacturer. 
Per  Cent. 
3 
4 
5 
2 
1.65 
3-io 
2.1 
0.80 
2.10 
