Doekhie A, Slade M N, Cliff L, Weaver L, Castaing R, Paulin J, Chen Y-C, Edler K J, Koumanov F, Marchbank K J, van den Elsen J M H, Sartbaeva A
Department of Chemistry, University of Bath Claverton Down Bath BA2 7AY UK
Material and Chemical Characterisation Facility, University of Bath Claverton Down Bath BA2 7AY UK.
RSC Adv. 2020 Aug 12;10(50):29789-29796. doi: 10.1039/d0ra06412b. eCollection 2020 Aug 10.
Ensilication is a novel method of protein thermal stabilisation using silica. It uses a modified sol-gel process which tailor fits a protective silica shell around the solvent accessible protein surface. This, electrostatically attached, shell has been found to protect the protein against thermal influences and retains its native structure and function after release. Here, we report the calorimetric analysis of an ensilicated model protein, hen egg-white lysozyme (HEWL) under several ensilication conditions. DSC, TGA-DTA-MS, CD, were used to determine unfolding temperatures of native, released and ensilicated lysozyme to verify the thermal resilience of the ensilicated material. Our findings indicate that ensilication protects against thermal fluctuations even at low concentrations of silica used for ensilication. Secondly, the thermal stabilisation is comparable to lyophilisation, and in some cases is even greater than lyophilisation. Additionally, we performed a mouse study using lysozyme to demonstrate the antigenic retention over long-term storage. The results suggest that protein is confined within the ensilicated material, and thus is unable to unfold and denature but is still functional after long-term storage.
硅化是一种使用二氧化硅实现蛋白质热稳定的新方法。它采用改良的溶胶 - 凝胶工艺，在溶剂可及的蛋白质表面量身定制一层保护性的二氧化硅壳。已发现这层通过静电附着的壳能保护蛋白质免受热影响，并在释放后保持其天然结构和功能。在此，我们报告了在几种硅化条件下对硅化模型蛋白——鸡蛋清溶菌酶（HEWL）的量热分析。差示扫描量热法（DSC）、热重 - 差热 - 质谱联用（TGA - DTA - MS）、圆二色光谱法（CD）被用于测定天然、释放态和硅化溶菌酶的解链温度，以验证硅化材料的热稳定性。我们的研究结果表明，即使在用于硅化的二氧化硅浓度较低时，硅化也能防止热波动。其次，热稳定性与冻干相当，在某些情况下甚至优于冻干。此外，我们用溶菌酶进行了一项小鼠研究，以证明长期储存后的抗原保留情况。结果表明，蛋白质被限制在硅化材料内，因此无法展开和变性，但在长期储存后仍具有功能。
