Investigation and quantification of electroanalytic properties of pencil graphite electrode and podophylotoxin

Podophyllotoxin , which is included in antineoplastic drugs and investigated in this study, is used in the treatment of cancer (breast cancer, prostate cancer, colon cancer, small cell lung cancer, lymphomas, and genital tumors) and warts. A sensitive and simple voltammetric method has been developed for the quantitation of podophyllotoxin using a disposable pencil graphite electrode (PGE). Electrochemical properties of podophyllotoxin were investigated by using squarewave (SW) and cyclic voltammetry(CV) technique using PG electrode. In the Britton Robinson (BR) buffer (pH 4,0) using SW voltammetry, podophyllotoxin yielded a very good voltammetric response at a +1.242 V (vs. Ag/AgCl) (after 60 s of accumulation at 0.0V). This process was used to quantify the compound in the concentration range of 1.24x10-8 –29.4x10-8 M (12.4-299.5 nM) with an observability limit of detection 2.55 nM (1.06 µg/L). The proposed method has been successfully applied to human urine samples.