Scholarlink

<p>Thermal treatment plays a critical role in defining the physicochemical organization and functional behavior of biosynthesized metal oxide nanoparticles. However, its influence on the surface and colloidal evolution of biosynthesized ZnO nanoparticles (ZnO-NPs) remains insufficiently understood. In this study, ZnO-NPs obtained using aqueous plant extracts were subjected to post-synthesis drying at 60&#xa0;°C or calcination at 500&#xa0;°C in order to evaluate thermally induced changes in surface chemistry, crystallographic organization, colloidal behavior, and antibacterial performance. FTIR and XPS analyses revealed a marked reduction of surface-associated organic fractions after calcination, indicating greater exposure of the ZnO surface sites. In contrast, XRD and UV–Vis analyses showed only minor variations in crystallinity and optical band gap, suggesting that the bulk crystalline and electronic structure of ZnO remained largely preserved after thermal treatment. The most pronounced modifications occurred at the colloidal level, with calcination promoting larger hydrodynamic diameters, increased polydispersity, and reduced zeta potential magnitude, indicating diminished electrostatic stabilization and greater aggregation in aqueous suspension. ESEM observations further revealed differences in aggregate organization and morphological homogeneity depending on the biosynthetic pathway. Calcined ZnO-NPs exhibited narrower and more reproducible minimum inhibitory concentration (MIC) values (0.078–0.156&#xa0;mg mL<sup>–1</sup>) against Gram-positive and Gram-negative bacteria. ZnO-NPs synthesized using <i>Inga jinicuil</i> displayed comparatively more homogeneous organization and improved antibacterial performance under both thermal conditions. Overall, the results indicate that thermal treatment predominantly restructures surface-associated fractions and colloidal organization rather than inducing major crystallographic or electronic modifications, thereby influencing the consistency of antibacterial performance in biosynthesized ZnO systems.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Thermal restructuring of surface chemistry and colloidal organization in biosynthesized ZnO nanoparticles: implications for antibacterial performance

  • 期刊论文

  • 发表日期：

    2026年7月16日

查看全文
  • Jorge Luis Torres-López,
  • Stephania Lázaro-Mass,
  • Susana De la Rosa-García,
  • Aranzazu Sierra-Fernández,
  • Mayra A. Alvarez-Lemus,
  • Abraham Gómez-Rivera,
  • Sergio Gómez-Cornelio

摘要

Thermal treatment plays a critical role in defining the physicochemical organization and functional behavior of biosynthesized metal oxide nanoparticles. However, its influence on the surface and colloidal evolution of biosynthesized ZnO nanoparticles (ZnO-NPs) remains insufficiently understood. In this study, ZnO-NPs obtained using aqueous plant extracts were subjected to post-synthesis drying at 60 °C or calcination at 500 °C in order to evaluate thermally induced changes in surface chemistry, crystallographic organization, colloidal behavior, and antibacterial performance. FTIR and XPS analyses revealed a marked reduction of surface-associated organic fractions after calcination, indicating greater exposure of the ZnO surface sites. In contrast, XRD and UV–Vis analyses showed only minor variations in crystallinity and optical band gap, suggesting that the bulk crystalline and electronic structure of ZnO remained largely preserved after thermal treatment. The most pronounced modifications occurred at the colloidal level, with calcination promoting larger hydrodynamic diameters, increased polydispersity, and reduced zeta potential magnitude, indicating diminished electrostatic stabilization and greater aggregation in aqueous suspension. ESEM observations further revealed differences in aggregate organization and morphological homogeneity depending on the biosynthetic pathway. Calcined ZnO-NPs exhibited narrower and more reproducible minimum inhibitory concentration (MIC) values (0.078–0.156 mg mL–1) against Gram-positive and Gram-negative bacteria. ZnO-NPs synthesized using Inga jinicuil displayed comparatively more homogeneous organization and improved antibacterial performance under both thermal conditions. Overall, the results indicate that thermal treatment predominantly restructures surface-associated fractions and colloidal organization rather than inducing major crystallographic or electronic modifications, thereby influencing the consistency of antibacterial performance in biosynthesized ZnO systems.