The demand for the development of new therapies and devices for controlled drug release has been continuously increasing, especially those based on materials sensitives to external stimuli, such as electricity. Therefore, in this work, acrylamide was polymerized in the presence of chitosan (CS), using N,N′-methylenebisacrylamide as cross-linking, followed by immersion in pyrrole aqueous solution and chemical polymerization to obtain an electroactive hydrogel of polyacrylamide/CS/polypyrrole (PA/CS/PPy) (67.5/7.5/25% wt.); this electroactive hydrogel was later used in drug delivery controlled by electricity studies. The synthesized PA/CS/PPy hydrogel was characterized by scanning electron microscopy, FTIR spectroscopy, and thermogravimetric analysis. It was observed that the hydrogel presented pores in the range of 50–200 μm with CS and PPy well incorporated to the cross-linked PA. The hydrogel swelling percentage (S) was determined at different pHs. It was observed that S was independent of pH, with S = 700% and a swelling kinetics described by the Fickian diffusion mechanism at alkaline pH. PA/CS/PPy hydrogel was used to absorb captopril (a drug for hypertension control), and its kinetics release at different applied potentials and pH was studied. Release kinetics were described by the Korsmeyer–Peppas model, while release mechanism was a Case-II transport without current at alkaline pH; under electrical stimuli, the mechanism presented an anomalous transport with ON–OFF profile, increasing the release rate with the applied voltage showing its electroactivity in the captopril release.

中文翻译：

---

电控制卡托普利释放的电活性聚丙烯酰胺/壳聚糖/聚吡咯水凝胶

开发用于控制药物释放的新疗法和设备的需求不断增加，尤其是那些基于对外部刺激（如电）敏感的材料的需求。因此，在这项工作中，丙烯酰胺在壳聚糖 (CS) 存在下聚合，使用 N,N'-亚甲基双丙烯酰胺作为交联，然后浸入吡咯水溶液并进行化学聚合，得到聚丙烯酰胺/CS/电活性水凝胶。聚吡咯 (PA/CS/PPy) (67.5/7.5/25% wt.); 这种电活性水凝胶后来用于由电学研究控制的药物输送。合成的 PA/CS/PPy 水凝胶通过扫描电子显微镜、FTIR 光谱和热重分析进行表征。据观察，水凝胶的孔隙范围为 50-200 μm，CS 和 PPy 很好地结合到交联 PA 中。水凝胶溶胀率（S ) 在不同的 pH 值下测定。据观察，S与 pH 无关，S  = 700%，并且在碱性 pH 下，溶胀动力学由 Fickian 扩散机制描述。PA/CS/PPy水凝胶用于吸收卡托普利（一种控制高血压的药物），并研究了其在不同外加电位和pH值下的释放动力学。释放动力学由 Korsmeyer-Peppas 模型描述，而释放机制是在碱性 pH 下没有电流的 Case-II 传输；在电刺激下，该机制呈现出具有 ON-OFF 曲线的异常传输，随着施加的电压增加释放速率，显示其在卡托普利释放中的电活性。