In the field of essential oil research, the low water solubility of essential oils (EOs) causes several problems, not only in pharmaceutical applications, but also in microbiological experiments. The aim of our work was to prepare Pickering emulsions with tea tree, thyme, and anise EOs stabilized with silica nanoparticles, in order to enhance their availability for microbiological tests. We have examined the influence of surface properties and concentration of silica nanoparticles and dispergation energy on emulsion stability and droplet size. In vitro diffusion experiments have been performed on model agar gel membranes, with the stable Pickering emulsions and conventional emulsions of EOs stabilized with Tween 80 surfactant. We have examined the influence of surface modifying group type, surface coverage of silica nanoparticles, and droplet size of the emulsions on the diffusion properties of the EOs. Our results show that highly stable Pickering emulsions can be prepared with silica nanoparticles of 20 nm diameter and 20% of surface covered with ethyl groups, in a wide EO concentration range. The cumulative amount of the EO was more effective in Pickering emulsions than in conventional emulsions for tea tree and thyme EOs, whereas the opposite case was true for anise EO. As the droplet size of the Pickering emulsion decreases, the cumulative concentration of the EO increases. In this work, we have shown that the Pickering emulsions of EOs are a suitable form for EO transport through complex membranes, and hopefully can be effectively applied in microbiological and pharmaceutical experiments.

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二氧化硅纳米粒子稳定的精油Pickering乳液的制备及体外扩散研究

在香精油研究领域，香精油（EOs）的低水溶性不仅在药物应用中，而且在微生物实验中也引起一些问题。我们的工作目的是用二氧化硅纳米粒子稳定化的茶树，百里香和茴香EO制备Pickering乳液，以提高其在微生物学测试中的可用性。我们已经检查了二氧化硅纳米颗粒的表面性质和浓度以及分散能对乳液稳定性和液滴尺寸的影响。已经在模型琼脂凝胶膜上进行了体外扩散实验，使用了稳定的Pickering乳液和用Tween 80表面活性剂稳定的EOs常规乳液。我们研究了表面改性基团类型​​，二氧化硅纳米颗粒的表面覆盖率，乳液的液滴大小对EOs扩散性能的影响。我们的结果表明，可以在宽的EO浓度范围内用直径20 nm的二氧化硅纳米颗粒和20％的被乙基覆盖的表面制备高度稳定的Pickering乳液。在Pickering乳液中，EO的累积量比茶树和百里香EO的常规乳液更有效，而茴香EO则相反。随着Pickering乳液的液滴尺寸减小，EO的累积浓度增加。在这项工作中，我们已经表明，EO的Pickering乳液是EO通过复杂膜运输的合适形式，希望可以有效地应用于微生物学和药物实验。我们的结果表明，可以在宽的EO浓度范围内用直径20 nm的二氧化硅纳米颗粒和20％的被乙基覆盖的表面制备高度稳定的Pickering乳液。在Pickering乳液中，EO的累积量比茶树和百里香EO的常规乳液更有效，而茴香EO则相反。随着Pickering乳液的液滴尺寸减小，EO的累积浓度增加。在这项工作中，我们已经表明，EO的Pickering乳液是EO通过复杂膜运输的合适形式，希望可以有效地应用于微生物学和药物实验。我们的结果表明，可以在宽的EO浓度范围内用直径20 nm的二氧化硅纳米颗粒和20％的被乙基覆盖的表面制备高度稳定的Pickering乳液。在Pickering乳液中，EO的累积量比茶树和百里香EO的常规乳液更有效，而茴香EO则相反。随着Pickering乳液的液滴尺寸减小，EO的累积浓度增加。在这项工作中，我们已经表明，EO的Pickering乳液是EO通过复杂膜运输的合适形式，希望可以有效地应用于微生物学和药物实验。在很宽的EO浓度范围内。在Pickering乳液中，EO的累积量比茶树和百里香EO的常规乳液更有效，而茴香EO则相反。随着Pickering乳液的液滴尺寸减小，EO的累积浓度增加。在这项工作中，我们已经表明，EO的Pickering乳液是EO通过复杂膜运输的合适形式，希望可以有效地应用于微生物学和药物实验。在很宽的EO浓度范围内。在Pickering乳液中，EO的累积量比茶树和百里香EO的常规乳液更有效，而茴香EO则相反。随着Pickering乳液的液滴尺寸减小，EO的累积浓度增加。在这项工作中，我们已经表明，EO的Pickering乳液是EO通过复杂膜运输的合适形式，希望可以有效地应用于微生物学和药物实验。