Voltammetric Determination of 2′‐Deoxyadenosine and Adenine in Urine of Patients with Hepatocellular Carcinoma Using Fullerene‐C60‐modified Glassy Carbon Electrode

A fullerene‐C60‐modified glassy carbon electrode has been examined for the simultaneous determination of 2′‐deoxyadenosine (2′‐dAdo) and adenine in human blood and urine using Osteryoung square‐wave voltammetry (OSWV) at pH 7.2. Compared to bare glassy carbon electrode (GCE), the modified electrode displays a shift of the oxidation potential in the negative direction with significant increase in the peak current for both the analytes. At modified electrode well‐defined anodic peaks at potential of 1248 mV and 994 mV are observed for 2′‐dAdo and adenine respectively. Linear calibration curves were obtained within the concentration range 10 nM to 100 μM for both the compounds in 0.1 M phosphate buffer solution (PBS) with the limit of detection 0.8×10−8 M and 0.95×10−8 M for 2′‐dAdo and adenine respectively. The analytical utility of the present method is demonstrated by quantitative detection of 2′‐dAdo and adenine in human urine of normal subjects as well as in patients with hepatocellular carcinoma. Interfering effect of some coexisting metabolites has also been reported.