Abstract Studies of the equilibrium and thermodynamic aspects of the adsorption of isoniazid onto a pharmaceutical-grade palygorskite and features of the resultant clay drug nanohybrid systems were carried out. Equilibrium studies were performed in aqueous medium at different times and temperatures. The overall adsorption process was explained as the result of two simple processes: drug adsorption on the activated sites of palygorskite and a slight precipitation phase of drug molecules over the adsorbed monolayer. Formation of the nanohybrid was spontaneous, exothermic and exoentropic, obtaining an increase in the thermodynamic stability of the system (ΔH = − 48,82 kJ/mol; ΔS = − 0.14 kJ/mol K). A full and comprehensive study of the solid state characterization corroborated the effective interaction between the components. Total amount of INH loaded was about 20% w/w. FTIR spectra revealed the interaction via water bridges between the endocyclic N of the drug and surface OH groups of palygorskite. Surface charge studies confirmed the non-electrostatic nature of the interactions.

中文翻译：

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坡缕石-异烟肼纳米杂化物的吸附与表征

摘要 进行了异烟肼吸附到药物级坡缕石上的平衡和热力学方面的研究以及所得粘土药物纳米杂化系统的特征。在不同时间和温度下在水性介质中进行平衡研究。整个吸附过程被解释为两个简单过程的结果：坡缕石活化位点上的药物吸附和药物分子在吸附单层上的轻微沉淀相。纳米杂化物的形成是自发的、放热的和外熵的，从而提高了系统的热力学稳定性（ΔH = - 48,82 kJ/mol；ΔS = - 0.14 kJ/mol K）。对固态表征的全面而全面的研究证实了组件之间的有效相互作用。加载的 INH 总量约为 20% w/w。FTIR 光谱揭示了药物的环内 N 与坡缕石的表面 OH 基团之间通过水桥的相互作用。表面电荷研究证实了相互作用的非静电性质。