Swe Mya Thet Htar, Asavapichayont Panida
Department of Pharmaceutical Technology, Faculty of Pharmacy, Silpakorn University, 6 Rajamankha Nai Rd., Amphoe Muang, Nakhon Pathom 73000, Thailand.
Pharmaceutical Biopolymer Group (PBiG), Faculty of Pharmacy, Silpakorn University, Nakhon Pathom 73000, Thailand.
Asian J Pharm Sci. 2018 Sep;13(5):485-497. doi: 10.1016/j.ajps.2018.04.006. Epub 2018 May 29.
Oleogels contain oil or a non-polar liquid which is gelled with an agent called an organogelator. The aim of this study was to evaluate the effects of the addition of silicone oil (cyclopentasiloxane) to the gelation process and to the properties of sorbitan monostearate (SMS)-sesame oil oleogel and compared with that of SMS-sesame oil oleogel and SMS-cyclopentasiloxane oleogel. Three different oil phases; sesame oil phase, cyclopentasiloxane phase and a mixture of cyclopentasiloxane and sesame oil, were used to prepare oleogels with SMS gelator. The critical gelling concentrations (CGC) for oleogels were determined using different concentration of SMS in a range of 5%-22% (w/w). The characterization of the developed oleogels was done using Fourier transform infrared spectroscopy (FTIR), polarized light microscope, rheometer, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The addition of cyclopentasiloxane reduced the CGC of SMS-sesame oil oleogel from 20% to 10% (w/w). In microscopic characterization, the oleogels with a mixture of oil phases showed the longer and thicker three-dimensional gel network than that of oleogels with sesame oil and cyclopentasiloxane. FTIR studies demonstrated that this network formation was mainly due to hydrogen bonding. Rheological measurements revealed that the combination of cyclopentasiloxane and sesame oil produced strong gel with higher complex modulus values and longer linear viscoelastic region than oleogels prepared with sesame oil and cyclopentasiloxane. In addition, oleogels with the combination of the two oils had higher enthalpy (Δ ) and entropy (Δ ) thus could increase thermodynamic stability of the oleogels. Therefore, the addition of cyclopentasiloxane can improve the physical, thermal properties and stability of SMS-sesame oil oleogel, provide greater sensory profile and better product aesthetics. The developed oleogel can be a novel carrier for topical drug delivery.
油凝胶含有油或非极性液体，这些物质会与一种称为有机凝胶剂的试剂形成凝胶。本研究的目的是评估添加硅油（环戊硅氧烷）对凝胶化过程以及对脱水山梨醇单硬脂酸酯（SMS）-芝麻油油凝胶性质的影响，并将其与SMS-芝麻油油凝胶和SMS-环戊硅氧烷油凝胶进行比较。使用三种不同的油相；芝麻油相、环戊硅氧烷相以及环戊硅氧烷和芝麻油的混合物，与SMS凝胶剂一起制备油凝胶。使用5%-22%（w/w）范围内不同浓度的SMS测定油凝胶的临界凝胶浓度（CGC）。使用傅里叶变换红外光谱（FTIR）、偏光显微镜、流变仪、X射线衍射（XRD）和差示扫描量热法（DSC）对所制备的油凝胶进行表征。添加环戊硅氧烷可使SMS-芝麻油油凝胶的CGC从20%降至10%（w/w）。在微观表征中，含有混合油相的油凝胶比含有芝麻油和环戊硅氧烷的油凝胶显示出更长、更厚的三维凝胶网络。FTIR研究表明，这种网络形成主要归因于氢键。流变学测量表明，环戊硅氧烷和芝麻油的组合产生了具有更高复数模量值和比用芝麻油和环戊硅氧烷制备的油凝胶更长的线性粘弹性区域的强凝胶。此外，含有两种油组合的油凝胶具有更高的焓（Δ ）和熵（Δ ），因此可以提高油凝胶的热力学稳定性。因此，添加环戊硅氧烷可以改善SMS-芝麻油油凝胶的物理、热性质和稳定性，提供更好的感官特性和产品美观度。所开发的油凝胶可以成为局部药物递送的新型载体。
