A copper nano particles and cerium (IV) oxide modified carbon nanotube based composite on glassy carbon electrode (Cu−CeO₂/MWCNT/GCE) was fabricated for simultaneous determination of guanine and adenine. The surface morphology, chemistry and conductance of the prepared electrodes were characterized by scanning electron microscopy (SEM), energy dispersion X‐ray (EDX), X‐Ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). The Cu−CeO₂/MWCNT/GCE improved electrochemical behaviour of guanine and adenine compared to other electrodes. The modified electrode was also used for individual and simultaneous determination of guanine and adenine. Under optimized conditions, the calibration curves were obtained linearly in the range of 0.20 to 6.00 μM for the guanine and 0.10 to 8.0 μM for the adenine by differential pulse voltammetry. The limits of detection of guanine and adenine were calculated as 0.128 and 0.062 μM, respectively. Interferences studies were also performed in the presence of inorganic and organic compounds. Moreover, the determination of guanine and adenine contents were carried out in a calf thymus DNA sample by the developed method with satisfactory results.

中文翻译：

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用于同时测定鸟嘌呤和腺嘌呤的Cu-CeO2涂层多壁碳纳米管复合电极的制备

制备了铜纳米颗粒和氧化铈（IV）修饰的碳纳米管复合材料，该复合材料位于玻璃碳电极上（Cu-CeO ₂ / MWCNT / GCE），用于同时测定鸟嘌呤和腺嘌呤。通过扫描电子显微镜（SEM），能量色散X射线（EDX），X射线光电子能谱（XPS）和电化学阻抗谱（EIS）表征了所制备电极的表面形态，化学性质和电导率。Cu-CeO ₂/ MWCNT / GCE与其他电极相比，改善了鸟嘌呤和腺嘌呤的电化学行为。修饰的电极还用于单独和同时测定鸟嘌呤和腺嘌呤。在优化条件下，通过差分脉冲伏安法在鸟嘌呤0.20至6.00μM和腺嘌呤0.10至8.0μM范围内线性获得校准曲线。鸟嘌呤和腺嘌呤的检出限分别计算为0.128和0.062μM。在存在无机和有机化合物的情况下也进行了干扰研究。此外，采用改进的方法测定了小牛胸腺DNA样品中的鸟嘌呤和腺嘌呤含量，结果令人满意。