Recent years have witnessed a tremendous interest in the use of essential oils in biomedical applications due to their intrinsic antimicrobial, antioxidant, and anticancer properties. However, their low aqueous solubility and high volatility compromise their maximum potential, thus requiring the development of efficient supports for their delivery. Hence, this manuscript focuses on developing nanostructured systems based on Fe₃O₄@SiO₂ core–shell nanoparticles and three different types of essential oils, i.e., thyme, rosemary, and basil, to overcome these limitations. Specifically, this work represents a comparative study between co-precipitation and microwave-assisted hydrothermal methods for the synthesis of Fe₃O₄@SiO₂ core–shell nanoparticles. All magnetic samples were characterized by X-ray diffraction (XRD), gas chromatography-mass spectrometry (GC-MS), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetry and differential scanning calorimetry (TG-DSC), and vibrating sample magnetometry (VSM) to study the impact of the synthesis method on the nanoparticle formation and properties, in terms of crystallinity, purity, size, morphology, stability, and magnetization. Moreover, the antimicrobial properties of the synthesized nanocomposites were assessed through in vitro tests on Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. In this manner, this study demonstrated the efficiency of the core–shell nanostructured systems as potential applications in antimicrobial therapies.

中文翻译：

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用精油功能化的氧化铁-二氧化硅核-壳纳米颗粒用于抗菌治疗

近年来，由于其固有的抗菌、抗氧化和抗癌特性，人们对精油在生物医学应用中的使用产生了极大的兴趣。然而，它们的低水溶性和高挥发性损害了它们的最大潜力，因此需要开发有效的载体来传递它们。因此，本手稿重点开发基于 Fe ₃ O ₄ @SiO ₂核壳纳米粒子和三种不同类型的精油（即百里香、迷迭香和罗勒）的纳米结构系统，以克服这些限制。具体而言，这项工作代表了共沉淀法和微波辅助水热法合成 Fe ₃ O ₄的比较研究@SiO ₂核壳纳米粒子。所有磁性样品均通过 X 射线衍射 (XRD)、气相色谱-质谱 (GC-MS)、傅里叶变换红外光谱 (FTIR)、动态光散射 (DLS)、zeta 电位、扫描电子显微镜 (SEM) 进行表征、透射电子显微镜 (TEM)、热重和差示扫描量热法 (TG-DSC) 以及振动样品磁强法 (VSM) 来研究合成方法对纳米颗粒形成和性质的影响，包括结晶度、纯度、尺寸、形态、稳定性和磁化强度。此外，合成的纳米复合材料的抗菌性能通过对金黄色葡萄球菌、铜绿假单胞菌、大肠杆菌和白色念珠菌。通过这种方式，这项研究证明了核壳纳米结构系统在抗菌治疗中的潜在应用的效率。