The use of 7,7,8,8-tetracyanoquinodimethane for the determination of nortriptyline and desipramine in tablets

A sensitive and selective spectrophotometric method is described for the assay of nortriptyline and desipramine. The method is based on the interaction of these drugs as electron donors with 7,7,8,8-tetracyanoquinodimethane (TCNQ) as a pi-acceptor in acetonitrile at 80 degrees C, to give highly coloured chromogens which exhibit maximum absorption at 567 nm. The proposed method was successfully applied to the determination of these drugs (as salts) in sugar-coated tablets. (C) 1999 Elsevier Science S.A. All rights reserved