Selective and sensitive electrochemical sensing of serotonin in human blood serum by means of electrochemically treated pencil graphite electrode

Authors : Ali Özcan

Pages : 551-562

Doi:10.18038/btda.63537

View : 20 | Download : 11

Publication Date : 2016-10-03

Article Type : Research Paper

Abstract :Electrochemical determination of serotonin (SER) in blood serum was investigated by electrochemically treated pencil graphite (ETPG) electrode for the first time. The electro-catalytic effect of ETPG shifted the oxidation potential of SER towards more cathodic direction (40 mV). The high surface area of ETPG together with its electro-catalytic effect increased the oxidation peak current values tremendously (forty times) according to bare PG. Moreover, the ETPG electrode allowed the oxidation of SER and uric acid (UA) at separate potential values that was not possible in the case of bare PG. It was observed that the interference effect of UA, which was a major component of blood serum, was negligible at pH value of 1.6. The ETPG showed good performance for the determination of SER with a linear range between 0.005 μM and 1.0 μM. The relative standard deviation of ten repetitive measurements of 1.0 μM SER was calculated as 2.8 % indicating highly reproducible response of ETPG electrode. The detection limit was calculated as 1.0 nM (S / N = 3). The analytical application of the proposed method was successfully tested in blood serum samples and it was compared with a previously published HPLC method.
Keywords : Serotonin, Electrochemically treated pencil graphite, Uric acid, Blood serum, Voltammetry