Mercaptopurine has been a standard component of long-term continuing treatment for childhood lymphoblastic leukaemia, whereas 6-thioguanine has been mainly used for intensification courses.

In this paper, the Electrochemistry behavior of the anticancer drugs 8-azaguanine (8-ag) and 6-mercaptopurine (6-mp) have been studied and the interaction of 8-ag with DNA has been studied too.

A end-column amperometric detection method with capillary electrophoresis for determination of 2-amino-6-mercaptopurine and 8-azaguanine has been established.