Page 83 - Analytical Chemistry I E-book
P. 83
Determination of ester drugs
• They are analyzed using back titration. The procedure starts with
heating the sample in the presence of an excess of standard
base. Hydrolysis reaction occurs which is also is called
saponification.
• Saponification is the reaction by which an ester is hydrolyzed in
alkaline solution to give an alcohol and an acid salt (conjugate
base).
R1COOR2 + OH– ⎯→ R1COO– + R2OH + H2O
• After saponification is complete, the excess base is titrated with a
standard acid solution.
