THE  AMERICAN  • 
JOURNAL  OF  PHARMACY. 
APRIL,  1876. 
ASSAY  OF  ATROPIA  IN  EXTRACTS  OF  BELLADONNA. 
BY  JOSEPH   LE   ROY  WEBBER,  PH.G. 
[Extract  from  an  Inaugural  Essay.) 
In  order  to  determine  the  relative  value  of  inspissated  juices  and 
alcoholic  narcotic  extracts,  commercial  and  officinal,  an  assay  of  the 
alkaloid  in  one  of  the  most  important  of  this  class,  namely,  the  extract 
of  belladonna,  was  made  with  care  and  accuracy. 
Extracts  of  belladonna  were  purchased,  representing  the  principal 
houses  of  this  country,  and  those  of  Europe  which  have  a  very 
extended  sale  in  this  country.  When  purchased,  each  package  had  on 
it  the  manufacturer's  label,  and  was  in  the  original  package.  The 
process  for  determining  their  value  was  as  follows  :  10  grams  of  the 
extract  was  treated  with  an  equal  weight  of  water,  and  subjected  to  a 
gentle  heat  until  the  extract  was  reduced  to  a  syrupy  consistence. 
90  c.c.  of  alcohol  was  then  added,  digested  and  strained,  and  the 
residue  treated,  3  times  successively,  in  a  similar  manner.  To  the 
mixed  liquids  4  grams  of  lime  was  added,  previously  hydrated  and  in 
powder,  and  the  flask  frequently  shaken  during  twelve  hours.  The 
lime  decomposes  the  salt  of  atropia,  and  removes  the  organic  acid  and 
coloring  matter  by  subsequent  filtration.  The  filter  was  washed  with 
alcohol ;  diluted  sulphuric  acid  was  then  added  to  the  filtrate,  until 
the  liquid  acquired  an  acid  reaction,  and  the  precipitate  of  sulphate  of 
calcium  and  coloring  matter  removed  by  filtration,  and  the  filter 
washed.  The  alcohol  was  then  removed  by  evaporation,  in  divided 
portions,  at  a  gentle  heat,  water  added  to  the  mixed  liquids  and  thrown 
on  a  wetted  filter,  and  sufficient  water  added  to  the  filter  to  make  the 
solution  of  sulphate  of  atropia  measure  100  c.c.  The  atropia  having 
been  separated  from  much  of  the  coloring  matter,  the  quantitative 
results  were  obtained  by  Mayer's  process,  namely,  a  volumetric 
solution  of  iodohydrargyrate  of  potassium,  or  rather  of  corrosive 
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