310  Estimation  of  Morphine  in  Pills,  Etc.  { Am'Jl'J10;Jiri9uarm- 
Solvent.  Wt.  of  cryst.  morphine  in  10  c.c.      Solubility  w-v. 
Alcohol   0.0547  Gm  1-182.6 
Chloroform   0.0110  Gm  1-909 
Alcohol        1  )  r  .  >  n  s 
~U1      r  \  0-1316  Gm  1-76 
Chloroform  2  J 
The  solubility  of  precipitated  morphine  crystals  (dried  below 
6o°  C.)  in  the  same  solvents  was  also  determined,  the  average  of  a 
number  of  estimations  being : 
Solvent.  Wt.  of  cryst.  morphine  in  10  c.c.      Solubility  w-v. 
Alcohol   0.0421  Gm  1-237.5 
Chloroform   0.0025  Gm   1-4000 
Alcohol         1  1  .0  r  o 
~,  ,      ,   0.1258  Gm  1-80 
Chloroform  2  J 
Also  the  solubility  of  crystalline  morphine  in  mixtures  containing 
varying  proportions  of  alcohol  and  chloroform: 
Solvent.  Wt.  of  cryst.  morphine  in  10  c.c.  Solubility. 
Alcohol        1  I  Q  I       Qm  ^  ^ 
Chloroform  I  J 
Alcohol  1 
Chloroform  2 
\  0.1258  Gm  1-80 
Alcohol        1  1   o  o879  Gm  1-114 
Chloroform  4  J 
Alcohol  1 
Chloroform  8 
.0.512  Gm  I-I95.5 
Based  on  these  experiments,  the  following  assay  method  is 
recommended : 
A  number  of  pills  or  tablets,  or  a  quantity  of  the  sample  for 
assay  containing  not  more  than  0.5  Gm.  morphine  (preferably  from 
0.1  to  0.2  Gm.),  is  dissolved  in  a  few  cubic  centimetres  of  acidulated 
water,  either  in  a  separator  or  in  a  beaker,  and  then  transferred  to 
a  separator,  keeping  the  volume  of  the  liquid  as  small  as  possible 
(from  5  to  10  c.c.)  ;  add  from  15  to  25  c.c.  of  mixture  of  alcohol  1 
part  and  chloroform  2  parts  by  volume  and  2  or  3  c.c.  of  10  per  cent, 
solution  of  ammonia,  or  sufficient  to  make  distinctly  alkaline. 
Stopper  the  separator  and  shake  well  for  2  or  3  minutes.  After 
separation,  which  usually  takes  place  inside  of  a  few  minutes,  draw 
off  the  chloroformic  solution,  filter  through  cotton,  well  wet  with 
chloroform,  into  a  wide-mouth  flask  or  beaker  of  about  150  c.c. 
capacity.    Repeat  the  extraction  with  two  further  like  portions  of 
