Abstract In this work, we report on highly transparent and stable high internal phase emulsions (HIPEs) stabilized by protein in general and globular proteins in particular using a refractive index (RI)-matching technique. Sucrose (50 wt.%) was added in the aqueous phase to match the RI of the oil phase (dodecane). In the presence of 50 wt.% sucrose, gel-like HIPEs (oil fraction of 0.75) could be stabilized by bovine serum albumin (BSA - a representative globular protein) at a concentration in the aqueous phase as low as 0.3 wt.%. In addition to achieving high transparency, the presence of 50 wt.% sucrose remarkably improved the emulsification performance of BSA and facilitated the formation of HIPE gels. The improvements were largely associated with high surface coverage via the formation of bridging droplets. The presence of 50 wt.% sucrose transformed BSA into a soft nanoparticle with high structural integrity that could resist the adsorption-induced structural disruption at the interface. The RI-matching strategy to fabricate transparent HIPE gels could be applied to other proteins. The findings are of interest for providing a facile strategy to fabricate biocompatible and highly transparent HIPE gels with great potential in the food, healthcare and light-induced catalysis fields.

中文翻译：

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仅由蛋白质稳定的透明高内相乳液凝胶

摘要在这项工作中，我们报告了高度透明和稳定的高内相乳液 (HIPE)，它通常由蛋白质和球状蛋白质稳定，特别是使用折射率 (RI) 匹配技术。将蔗糖 (50 wt.%) 添加到水相中以匹配油相（十二烷）的 RI。在 50 wt.% 蔗糖的存在下，凝胶状 HIPEs（0.75 的油分数）可以通过水相中浓度低至 0.3 wt.% 的牛血清白蛋白（BSA - 一种代表性的球状蛋白）来稳定。除了获得高透明度外，50 wt.% 蔗糖的存在显着改善了 BSA 的乳化性能，并促进了 HIPE 凝胶的形成。这些改进主要与通过形成桥接液滴的高表面覆盖率有关。50 重量的存在。% 蔗糖将 BSA 转化为具有高结构完整性的软纳米颗粒，可以抵抗界面处吸附引起的结构破坏。制造透明 HIPE 凝胶的 RI 匹配策略可应用于其他蛋白质。这些发现为制造生物相容性和高度透明的 HIPE 凝胶提供了一种简便的策略，在食品、医疗保健和光诱导催化领域具有巨大潜力。