Simultaneous determination of uric acid, xanthine, hypoxanthine and caffeine in human blood serum and urine samples using electrochemically reduced graphene oxide modified electrode

Bridged β-cyclodextrin-functionalized MWCNT with higher supramolecular recognition capability: The simultaneous electrochemical determination of three phenols

“…2D, curve b). A similar phenomenon was observed by Raj and John for electrochemically reduced graphene oxide modified GCE during the detection of uric acid, xanthine, hypoxanthine, and caffeine (Raj and John, 2013). In the case of β-CD-MWCNT/GCE, the oxidation currents of 4-AP, 4-CP, and 4-NP were enhanced compared with that of the bare and the MWCNT-modified GCEs, indicating that the β-CD molecules with enhanced supramolecular recognition capability that formed inclusion complexes with 4-AP, 4-CP, and 4-NP.…”

“…This increase indicated that the high surface area and high conductivity of the MWCNT increased the effective electrode area and improved the catalytic activity towards 4-AP and 4-CP oxidation. Another reason for the enhancement of oxidation current at the MWCNT/GCE is considered to be the π-π interaction between the 4-AP/4-CP and the MWCNT film on the GCE (Raj and John, 2013). It should be noted here that the peak of 4-NP was not appeared at the bare GCE (Fig.…”

Recent advances in electrochemical biosensing schemes using graphene and graphene-based nanocomposites

“…Similar behavior is also observed for the graphene/carbon fiber electrode (0.132 lM and 0.19-49.68 lM) [283], the electrochemically reduced GO/ITO electrode (0.30 lM and 0.3-100 lM) [284]. Nevertheless, the ERGO/1,6-hexadiamine/GCE exhibits linearity of 5-1000 lM with an LOD of 0.088 lM [285]. Graphene-based electrodes are extended for analysis of other important biomolecules such as serotonin, xanthine/hypoxanthine, epinephrine, norepinephrine, tryptamine, etc.…”

Electrochemical synthesis of a novel purine-based polymer and its use for the simultaneous determination of dopamine, uric acid, xanthine and hypoxanthine

“…The typical concentration of UA is 120-450 μmol L −1 in blood and 1.4-4.4 mmol L −1 in urine [5,6]; abnormal UA levels can cause several diseases, such as hyperuricemia, leukemia, and the Lesch-Nyhan syndrome [4,7]. The therapeutic XA level is 10-20 mg mL −1 in blood [8], and the content of XA in blood plasma and urine may provide sensitive indicators of certain pathologic states, especially for xanthinuria. HXA is formed during the degradation of adenosine triphosphate [9], and found as a minor purine base in tRNA [8].…”