24 
A  loin. 
Am.  Jour  Pharm. 
Jan.  1876. 
ALOIN. 
BY  CHARLES  L.  MITCHELL,  PH.  G. 
[Read  at  the  Pharmaceutical  Meeting,  Dec-  i\st,  1875.) 
The  subject  of  aloin  having  lately  been  again  brought  to  the  notice 
of  the  pharmaceutical  world  by  the  experiments  of  Mr.  Tilden,  it 
occured  to  the  writer  to  undertake  some  experiments  on  aloin,  in  order 
to  ascertain  if  a  good  article  could  not  be  prepared  by  some  reliable  pro- 
cess, not  too  difficult  for  general  adoption. 
The  grades  of  aloin,  as  found  in  the  market,  have  occasioned  much 
distrust  of  its  value  as  a  medicine,  on  account  of  the  unreliability  and 
uncertainty  attending  their  use,  very  often  being  almost  inert.  Aloin, 
when  of  a  good  character,  is  a  very  safe  and  efficient  cathartic  and 
purgative,  acting  freely  in  doses  of  from  1  to  3  grs.  It  affords  a  conve- 
nient and  efficacious  method  of  obtaining  the  remedial  effects  of  aloes 
in  a  concentrated  form. 
In  making  these  experiments  the  process  of  Mr.  Tilden  (Am.  "Jour. 
Pharm.  187 1.)  was  followed.  "  One  pound  of  good  Barbadoes  aloes 
was  broken  up  and  dissolved  with  heat  in  1  gal.  water,  acidulated  with 
f^ss  sulphuric  acid,  and  after  perfect  solution,  was  set  aside  for  twenty- 
tour  hours  to  cool.  The  supernatant,  clear  liquid  was  poured  ofF  from 
the  resin  (which  is  comparatively  inert),  and  evaporated  by  a  gentle  heat 
to  about  2  pints,  and  then  set  aside  for  several  days.  On  examining 
the  liquid  at  the  expiration  of  that  time,  a  heavy  crystalline  deposit  of 
a  yellow  color  was  found  on  the  bottom  and  sides  of  the  vessel.  This 
was  collected  on  a  filter,  washed  with  a  little  ice-cold  water  to  remove 
coloring  matter,  well  drained  and  dried.  This  aloin  is  rather  impure. 
It  can  be  rendered  quite  pure  by  dissolving  it  in  warm  water,  decolor- 
ing with  animal  charcoal,  and  again  evaporating  and  crystallizing. 
Aloin,  thus  obtained,  is  of  a  yellow  color,  crystalline,  and  of  an 
extremely  bitter,  aloetic  taste.  It  is  slightly  soluble  in  cold  water,  very 
soluble  in  hot  water,  and  soluble  in  alcohol.  The  yield  was  about  600 
grains. 
Some  of  this  aloin  was  made  up  into  pills,  and  it  purged  actively  in 
doses  of  2  grs. 
The  liquid  from  which  the  crystalline  deposit  had  been  separated 
was  evaporated  to  extract  consistence,  yielding  about  10  ounces  of  a 
very  good  article  of  extractum  aloes. 
The  main  point  to  be  considered  in  the  preparation  of  a  reliable 
article  of  aloin,  is  the  selection  of  a  good  grade  of  aloes.  Barbadoes 
