Institute of Nanotechnology & Advanced Materials, Chemistry Department, Bar-Ilan University, Ramat-Gan 52900, Israel.
Institute of Nanotechnology & Advanced Materials, Chemistry Department, Bar-Ilan University, Ramat-Gan 52900, Israel.
Mater Sci Eng C Mater Biol Appl. 2019 Apr;97:760-767. doi: 10.1016/j.msec.2018.12.093. Epub 2018 Dec 27.
This study presents a new process for hydrophilic formulation of liquid oils, by encapsulation and solidification of the oils within porous hollow silica microspheres of narrow size distribution. Jojoba [Simmondsia chinensis] oil was chosen as a model study due to its broad potential applications. Jojoba oil is produced from the seeds of the jojoba plant, which are rich in liquid wax. Today, jojoba oil is mainly used for applications such as pharmaceuticals and cosmetics. The oil is primarily used as a carrier oil that stabilizes sensitive active compounds, such as vitamins and other oils, which are susceptible to air oxidation or UV-light degradation. Silica (SiO) particles are used in many different industrial products such as food and cosmetics due to their chemical inertness. Here, uniform porous hollow SiO microspheres, composed of sintered SiO nanoparticles, were made by coating polystyrene template microspheres of narrow size distribution with three layers of SiO nanoparticles, followed by removal of the polystyrene core by combustion at 500 °C. The synthesis stages were characterized by SEM, TEM, FTIR and TGA analyses. The measurements confirmed the increasing content of SiO after each coating cycle and the absence of polystyrene in the final hollow particles. Jojoba oil was successfully encapsulated within the hollow SiO microspheres by heating/cooling cycles, reaching an encapsulation yield of up to 10 times of the SiO dry shell weight. The oil encapsulation was confirmed by a floatability test and confocal microscopy. The hollow SiO and the oil-filled microspheres were found non-toxic to HaCaT cell line, a spontaneously transformed human epithelial cell line from adult skin. Furthermore, the oil-filled SiO microspheres were dispersed in a hydrogel and exhibited a homogeneous water-based formulation that appeared stable after six months storage. In light of these findings, we offer these jojoba oil-filled particles as a model for hydrophilic formulation of oils in general and in particular as suitable candidates for pharmaceutical and cosmetic applications.
本研究提出了一种新的亲水性液态油制剂工艺，即将油包封并固化在多孔中空硅微球中。由于其广泛的潜在应用，选择霍霍巴油[西蒙得木（Simmondsia chinensis）]作为模型研究。霍霍巴油是从霍霍巴植物的种子中提取的，富含液态蜡。如今，霍霍巴油主要用于医药和化妆品等领域。该油主要用作载体油，可稳定易受空气氧化或紫外线降解的敏感活性化合物，如维生素和其他油类。由于其化学惰性，二氧化硅（SiO）颗粒被广泛应用于食品和化妆品等多种不同的工业产品中。在这里，通过用三层 SiO 纳米颗粒涂覆窄分布的聚苯乙烯模板微球，然后在 500°C 下燃烧除去聚苯乙烯核，制备了由烧结 SiO 纳米颗粒组成的均匀多孔中空 SiO 微球。通过 SEM、TEM、FTIR 和 TGA 分析对合成阶段进行了表征。测量结果证实，在每个涂覆循环后，SiO 的含量都会增加，并且最终的中空颗粒中没有聚苯乙烯。通过加热/冷却循环，成功地将霍霍巴油包封在中空 SiO 微球内，达到了 SiO 干壳重量 10 倍的包封产率。通过漂浮性测试和共聚焦显微镜证实了油的包封。中空 SiO 和充油微球对 HaCaT 细胞系（一种源自成人皮肤的自发转化的人上皮细胞系）无毒性。此外，充油的 SiO 微球分散在水凝胶中，形成了一种均匀的水基制剂，在六个月的储存后仍保持稳定。鉴于这些发现，我们将这些填充有霍霍巴油的颗粒作为一般油亲水制剂的模型，特别是作为适合医药和化妆品应用的候选材料。
