A Novel Carbon Paste Electrode for Potentiometric Determination of Vanadyl Ion

作者：Darroudi Abolfazl^*; Eshghi Hossein; Rezaeian Shima; Chamsaz Mahmoud; Bakavoli Mehdi; Haghbeen Kamahldin; Hosseiny Akram

来源：Iranian Journal of Chemistry and Chemical Engineering (International English Edition), 2015, 34(4): 89-96.

• Carbon paste electrode
• Potentiometry
• Vanadyl ion
• 2,4-diamino-7-methylbenzo[g]pteridine-5,10-dioxide

Carbon paste electrode was modified by disodium 2,4-diamino-7-methylbenzo[g] pteridine-5,10-dioxide to fabricate a sensor for potentiometric determination of vanadyl ion (VO2+) in aqueous medium. The new ligand was synthesized in three steps with high yield. The optimal composition of the carbon paste was made of graphite powder (64.5%), ionophore (16.6%), paraffin oil (17.8%), and sodium tetraphenylborate (NaTPB, 1.1%). The electrode exhibited a constant sensitivity of 30.20 +/- 0.5 mV to VO2+ ions over a concentration range of 5 mu M to 1 mM. The detection limit was calculated to be 5 mu M with a response time of less than 35 s. The electrode showed to be highly reproducible over a period of 3 weeks. This sensor exhibits high selectivity to VO2+ ions and was successfully employed for potentiometric titration of VO2+ ions with EDTA.

• 出版日期2015