Am.  Jour.  Pharm. 
}   Aspirin  and  Sodium  Salicylate  in  Powders. 
DETERMINATION  OF  ASPIRIN  AND  SODIUM 
SALICYLATE  IN  POWDERS. 
By  Reginald  Miller,  Chemical  Laboratory,  New  York  City  Dept.  of  Health. 
Among  samples  received  at  the  Laboratory  were  those  consist- 
ing of  aspirin  and  sodium  salicylate.  The  following  method  has 
been  found  satisfactory,  and  its  publication  may  assist  others  who 
are  doing  similar  work. 
Aspirin. — Weigh  the  collective  contents  of  several  packages,  mix 
thoroughly.  (If  sample  is  not  a  fine  powder,  grind  it  in  a  mortar 
until  it  is.)  Take  a  weighed  portion  corresponding  to  that  of  one 
package,  transfer  to  a  small  beaker,  add  an  equal  volume  of  clean 
sand,  and  8  or  10  mils  of  ethyl  ether,  stir  the  mass  with  a  glass  rod, 
allow  to  settle,  decant  through  a  small  dry  filter  paper,  repeat  the 
extraction  about  ten  times,  collect  the  filtrates  in  a  weighed  glass 
dish,  evaporate  to  dryness.  Weigh.1 
Residue  should  respond  to  the  following  tests : 
Cone,  nitric  acid — yellow,  gradually  deeper. 
Froede's  reagent — immediate  purple  coloration. 
Formaldehyde  sulphuric  acid — faint  red  color  after  one  or  two . 
minutes. 
Selenious  sulphuric  acid — No  change  in  color. 
Cone,  sodium  hydroxide — No  change  in  color. 
Solium  Salicylate. — To  the  beaker  containing  the  sand  and  the 
portion  insoluble  in  ether,  transfer  the  filter  paper  (that  was  used 
was  evaporated  to  small  bulk  and  the  residue  tested  for  iodine  by  Kendall's 
method.  Small  amounts  of  iodine  were  found.  These  findings  were  taken 
to  indicate  that  the  iodine-containing  fat  is  absorbed  to  some  extent  by  the 
skin.  It  is  generally  believed  that  potassium  iodide  is  not  absorbed  by  the 
unbroken  skin.  Therefore  it  seems  reasonable  to  suppose  that  the  principal 
iodine  effect's  obtainable  from  iodine  ointment  are  those  due  to  the  free 
iodine  contained  in  the  preparation,  supplemented  to  a  slight  extent  by  the 
iodine  which  is  contained  in  the  fatty  ointment  base.  Jour.  Biochem.,  ig, 
251  (1914). 
1  The  aspirin  may  be  checked  by  taking  a  weighed  portion  of  the  original 
sample  (about  .100  G.),  dissolve  it  in  95  per  cent,  alcohol  (neutral)  and 
titrate  it  with  &  sodium  hydroxide,  using  phenolphthalein  as  the  indicator. 
One  mil  of  sodium  hydroxide  =  .0180  G.  of  aspirin.  If  substances  are 
present  which  interfere  with  the  determination  directly  on  the  powder,  take 
a  weighed  portion  of  the  residue  (about  .050  G.)  and  titrate  with  the  $7 
alkali. 
