Voltammetric determination of N-nitrosamines in the hypoglycemic agent tolazamide

Summary Exposure to N-nitrosamines has been indicted as one cause of cancer and so their presence has to be controlled. Voltammetry has been used for the detection of N-nitrosamines and has the advantage that it can be applied to both volatile and non-volatile compounds.The proposed method consists in dissolving 50 mg of tolazamide drug in 1 M potassium hydroxide and, after deaeration, the solution is directly submitted to differential pulse polarography. The response at about —1.50 V (vs. Ag/AgCl reference electrode) is proportional to the N-nitrosamine content from 0.5 ppm to more than 1,000 ppm into the tolazamide sample, with a relative standard deviation of ± 3 – 4% at 1 ppm. The sensitivity of the proposed method is essentially limited by a sharp peak due to N-(hexahydro-1H-azepin)carbonyl]-4-methylbenzensulphonamide (usually present as impurity in tolazamide), that occurs at about –1.23 V (vs. Ag/AgCl reference electrode).

---

Voltammetrische Bestimmung von N-Nitrosaminen in dem hypoglykämischen Mittel Tolazamid