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在０．０２ｍｏｌ·Ｌ－１ＨＡｃ－ＮａＡｃ，ｐＨ４．０的底液中，二硝基番木鳖碱（ＤＮＳ）在汞电极上有一不可逆线性扫描还原峰，（ｖｓ．饱和Ａｇ／ＡｇＣｌ电极）。该峰具有明显吸附性。当ＤＮＳ浓度较小，扫描较快，搅拌富集时间较长时，电极反应完全为吸附态的ＤＮＳ的还原所控制，吸附型体为ＤＮＳ中性分子。测得ＤＮＳ在汞电极上的饱和吸附量为２．７５×１Ｏ－１１ｍｏｌ·ｃｍ－２，每个ＤＮＳ分子所占电极面积为６．０４ｎｍ２。探讨了吸附伏安法测定ＤＮＳ的最佳条件。可将非电活性的番木鳖碱硝化转化为ＤＮＳ，然后用吸附伏安法对番木鳖碱进行间接测定。
In 0.02 mol·L-1HAc-NaAc, pH4.0, DNS showed an irreversible linear reduction at mercury electrode (vs. Saturated Ag / AgCl electrode). The peak has obvious adsorbability. When the DNS concentration is smaller, the scanning speed is faster and the enrichment time is longer, the electrode reaction is completely controlled by the reduction of the adsorbed DNS, which is a DNS neutral molecule. The saturated adsorption capacity of DNS on mercury electrode was 2.75 × 10-11mol · cm-2, and the area occupied by each DNS molecule was 6.04nm2. The optimum conditions for the determination of DNS by adsorption voltammetry were discussed. Non-electroactive strychnine can be converted to DNS by indirect nitration, and then indirect determination of strychnine by adsorption voltammetry.