Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China; College of Pharmacy, Zunyi Medical University, Zunyi 563000, China.
Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China.
Talanta. 2015 Mar;134:354-359. doi: 10.1016/j.talanta.2014.11.042. Epub 2014 Nov 29.
A sensitive wall-jet/thin-layer amperometric electrochemical detector (ECD) coupled to high-performance liquid chromatography (HPLC) was developed for simultaneous determination of guanine (G) and adenine (A). The analytes were detected at a glassy carbon electrode (GCE) and the HPLC-ECD calibration curves showed good linearity (R(2)>0.997) under optimized conditions. Limits of detection for G and A are 0.6 nM and 1.4 nM (S/N=3), respectively, which are lower than those obtained with an UV-vis detector and a commercial electrochemical detector. We have successfully applied this HPLC-ECD to assess the contents of G and A in hydrochloric acid-digested calf thymus double-stranded DNA. In addition, we compared in detail the analysis of G and A by cyclic voltammetry (CV) and by the HPLC-ECD system on both bare GCE and electroreduced graphene oxide (ERGO) modified GCE. We found that the adsorption of G and A on the electrode surfaces can vary their anodic CV peaks and the competitive adsorption of G and A on the limited sites of the electrode surfaces can cause crosstalk effects on their anodic CV peak signals, but the HPLC-ECD system is insensitive to such electrode-adsorption and can give more reliable analytical results.
一种灵敏的壁喷/薄层安培电化学检测器（ECD）与高效液相色谱（HPLC）相结合，用于同时测定鸟嘌呤（G）和腺嘌呤（A）。在优化条件下，在玻碳电极（GCE）上检测到分析物，并且 HPLC-ECD 校准曲线具有良好的线性（R²>0.997）。G 和 A 的检测限分别为 0.6 nM 和 1.4 nM（S/N=3），低于使用紫外可见检测器和商业电化学检测器获得的检测限。我们已经成功地将这种 HPLC-ECD 应用于评估盐酸消化小牛胸腺双链 DNA 中 G 和 A 的含量。此外，我们详细比较了在裸 GCE 和还原氧化石墨烯（ERGO）修饰 GCE 上通过循环伏安法（CV）和 HPLC-ECD 系统分析 G 和 A 的情况。我们发现，G 和 A 在电极表面的吸附会改变它们的阳极 CV 峰，并且 G 和 A 在电极表面的有限位置上的竞争吸附会对它们的阳极 CV 峰信号产生串扰效应，但是 HPLC-ECD 系统对这种电极吸附不敏感，可以给出更可靠的分析结果。
