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用循环伏安法（ＣＶ）、电流采样极诸法（ＳＣＰ，即ＴＡＳＴ）、常规脉冲极谱法（ＮＰＰ）、微分脉冲极谱法（ＤＰＰ）、线性扫描伏安法（ＬＳＶ）、Ｏｓｔｅｒｙｏｕｎｇ方波伏安法（ＯＳＷＶ）和计时库仑法（ＣＣ）等电化学技术研究了抗癌药物８－氮鸟嘌呤（８－ａｚａｇｕａｎｉｎｅ，ｇｕａｎａｚｏｌｏ，简称８－ＡＧ）的极谱伏安行为．在 ０． １ｍｏｌ／Ｌ Ｈ２ＳＯ４底液中，８－ＡＧ有一良好的还原峰，峰电位（Ｅｐ）在－０． ９５Ｖ（ｖｓ．Ａｇ／ＡｇＣｌ，下同）附近，８－ＡＧ浓度在４×１０－６～８×１０－４ｍｏｌ／Ｌ范围内．峰高与浓度有良好的线性关系，线性相关系数ｒ＝０．９９９９～０．９９１０，检出限为１× １０－６ｍｏｌ／Ｌ．实验证明了该峰具有吸附性．本文提出了电极反应机理，它包括：酸性介质中８－ＡＧ的质子化、质子化的８－ＡＧ在汞电极上吸附以及完全不可逆的两电子还原过程．同时用量子化学计算方法（全略微分重叠法即ＣＮＤＯ／２）对８－ＡＧ和鸟嘌呤的各原子的净电荷以及Ｗｉｂｅｒｇ键级进行了计算，从理论上解释了８－ＡＧ的电化学还原机理。
Cyclic voltammetry (CV), current sampling methods (SCP, TAST), conventional pulse polarography (NPP), differential pulse polarography (DPP), linear sweep voltammetry (LSV) The polarographic voltammetric behavior of the anticancer drug 8-azaguanine (guanazolo, abbreviated as 8-AG) was studied by using electrochemical techniques such as atomic force microscopy (WAV) and time-dependent coulometry (CC) At 0. In 1mol / L H2SO4 solution, 8-AG has a good reduction peak, peak potential (Ep) -0. 95V (vs.Ag/AgCl, the same applies hereinafter) and 8-AG concentration was in the range of 4 × 10-6 to 8 × 10-4mol / L. The peak height and concentration had a good linear relationship, the linear correlation coefficient r = 0.9999 ~ 0.9910, the detection limit was 1 × 10-6mol / L. Experiments show that the peak has adsorption. In this paper, the electrode reaction mechanism is proposed, which includes the protonation of 8-AG in acidic medium, the adsorption of protonated 8-AG on mercury electrode and the irreversible two-electron reduction process. At the same time, the net charge and the Wiberg bond order of each atom of 8-AG and guanine were calculated by quantum chemical calculation method (all-differential differential overlap method: CNDO / 2), which theoretically explained the electrochemical reduction of 8-AG mechanism.