利用掺硼碳纳米管（BCNTs）/GC电极研究了鸟嘌呤（G）和腺嘌呤（A）的电化学氧化行为. 与GC和CNTs/GC电极相比，BCNTs/GC电极具有更强的电催化活性，且响应电流明显增加. 两混合样品在BCNTs/GC电极上的氧化峰间隔较大，可实现对A和G的同时检测.
In this work, the boron-doped carbon nanotubes (BCNTs) modified glassy carbon (GC) electrode was simply fabricated, and the electrochemical oxidation behaviors of guanine and adenine at the BCNTs/GC electrode were investigated. Compared with the bare GC and CNTs/GC electrodes, the BCNTs-modified electrode exhibited extraordinary electrocatalytic activity towards the oxidations of guanine and adenine as indicated by the obvious increase in current responses. Moreover, the peak separation between guanine and adenine was large enough for their potential recognition in mixture without any separation or pretreatment. Therefore, the simultaneous determination of guanine and adenine was successfully achieved. The BCNTs/GC electrode showed high sensitivity, wide linear range and low detection limit for the electrochemical determination of guanine and adenine. The possibility of the BCNTs/GC electrode for the determination of guanine and adenine in calf thymus DNA has also been evaluated. The BCNTs/GC electrode has advantages of excellent catalytic activity, selectivity and simplicity, which play a potential role in the development of the related DNA analysis.
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