苦参碱和槐定碱在多刺激响应性水凝胶薄膜电极上的可调控电化学行为及其逻辑门构建

采用苦参碱(Matrine, MT)和槐定碱(Sophoridine, SR)作为电活性药物分子探针, 考察了聚(N-异丙基)丙烯酰胺(PNIPAM)水凝胶薄膜的刺激响应特性; 并通过循环伏安(CV)法和扫描电子显微镜(SEM)研究了PNIPAM在不同外界刺激条件(如温度、 盐浓度和甲醇)下结构的改变. 在25 ℃时, 药物分子MT和SR在玻碳电极上产生较大的氧化峰电流, 随着温度升高至40 ℃, 药物分子探针的氧化峰电流逐渐减小. 考察了不同Na₂SO₄浓度和不同比例甲醇对PNIPAM水凝胶薄膜的影响, 发现MT和SR的氧化峰电流随着Na₂SO₄浓度(00.45 mol/L)和甲醇比例(040%)的升高而减小. 结果表明, MT和SR可作为分子探针研究PNIPAM水凝胶薄膜对环境的三重刺激响应性开关行为, 并可进一步构筑3-输入/2-输出的逻辑门系统.

Switchable Electrochemical Behavior of Matrine and Sophoridine at Multi-stimuli Responsive Hydrogel Film Electrode and Construction of Logic Gate†

Matrine(MT) and sophoridine(SR) were used as electroactive drug molecular probes to investigate the stimuli-responsive characteristics of the hydrogels poly(N-isopropyl)acrylamide(PNIPAM), and the changes of PNIPAM structure under different external stimuli(temperature, salt concentration and methanol) were observed by cyclic voltammetry(CV) method and scanning electron microscopy(SEM). The results show that at 25 ℃, MT and SR lead to a large oxidation peak current; when the temperature reached at 40 ℃, the oxidation peak currents of MT and SR are gradually reduced. The influence of different Na₂SO₄ concentration and different proportion of methanol on PNIPAM hydrogel were also investigated. The oxidation peak currents of MT and SR decreased with the increasing of Na₂SO₄ concentration(0—0.45 mol/L) and volume fraction of methanol ratio(0—40%). The results indicate that MT and SR could be used as molecular probes to investigate the switching behaviors of PNIPAM hydrogel films, and further constructed 3-input/2-output logic gate system.