NICOTINE. 
§ 335-] 
275 
M. Papovici 1 has proposed a method based on Kissling’s process of 
extraction, but the estimation is a polarimetric one ; in this way the 
difficulty of separating nicotine from ammonia is obviated. From 20 
to 40 grms. of dry tobacco are treated with 10 c.c. of alcoholic soda 
solution (6 per cent. NaOH in 100 c.c. of 57 per cent, alcohol) and 
extracted with ether in a Soxhlet apparatus. The ether extract is 
treated with 10 c.c. of a tolerably concentrated solution of phospho- 
molybdic acid in nitric acid and shaken ; the phosphomolybdate of 
nicotine (with ammonia) is precipitated, the ether is separated, and the 
precipitate treated with water to bring up the volume to 50 c.c. ; lastly, 
8 grms. of BaOH are added ; the yellow solution after standing for 
some hours is filtered and polarised. 
The following table is used :— 
Grms. of Nicotine in 
50 c.c. solution. 
Rotation in 2 dm. tube 
(minutes). 
One minute of a degree 
corresponds to grm. 
Nicotine. 
2-00 
337 
0-00594 
1-75 
298 
0-00588 
1-50 
258 
0-00582 
1-25 
217 
0-00576 
1-00 
175 
0-00572 
0-75 
133 
0-00564 
0-50 
89 
0-00562 
0-25 
45 
0-00556 
Mr Cox 2 has determined the amount of nicotine in a number of 
tobaccos as follows :— 
Twenty-five grammes (or more or less, according to the amount of the 
sample at disposal) of the dried and powdered tobacco were intimately 
mixed with slaked lime, and distilled in a current of steam until the con¬ 
densed steam was no longer alkaline ; the distillate was slightly acidu¬ 
lated with dilute H 2 S0 4 , and evaporated to a conveniently small bulk. 
This was made alkaline with soda, and agitated repeatedly with suc¬ 
cessive portions of ether. The separated batches of ethereal solution 
of nicotine were then mixed and exposed to the air in a cool place. 
This exposure to the air carries away ammonia, if any be present, as 
well as ether. 
Water was added to the ethereal residue, and the amount of nicotine 
present determined by decinormal H 2 S0 4 , using methyl-orange as an 
indicator. One c.c. of decinormal H 2 S0 4 represents 0-0162 grm. of 
nicotine (C 10 H 14 N 2 ). 
1 Ztschr. f. physiol. Chem., 1889, p. 445. 
2 Pharm. Journ., Jan. 20, p. 1894. 
