Background: Although the stability of proteins is of significance to maintain protein function for therapeutical applications, this remains a challenge. Herein, a general method of preserving protein stability and function was developed using gelatin films.

Methods: Enzymes immobilized onto films composed of gelatin and Ethylene Glycol (EG) were developed to study their ability to stabilize proteins. As a model functional protein, β-glucosidase was selected. The tensile properties, microstructure, and crystallization behavior of the gelatin films were assessed.

Results: Our results indicated that film configurations can preserve the activity of β-glucosidase under rigorous conditions (75% relative humidity and 37°C for 47 days). In both control films and films containing 1.8 % β-glucosidase, tensile strength increased with increased EG content, whilst the elongation at break increased initially, then decreased over time. The presence of β-glucosidase had a negligible influence on tensile strength and elongation at break. Scanning electron-microscopy (SEM) revealed that with increasing EG content or decreasing enzyme concentrations, a denser microstructure was observed.

Conclusion: In conclusion, the dry film is a promising candidate to maintain protein stabilization and handling. The configuration is convenient and cheap, and thus applicable to protein storage and transportation processes in the future.

背景：尽管蛋白质的稳定性对于维持蛋白质在治疗应用中的功能至关重要，但这仍然是一个挑战。在此，使用明胶膜开发了一种保持蛋白质稳定性和功能的通用方法。

方法：开发固定在由明胶和乙二醇（EG）组成的薄膜上的酶，以研究其稳定蛋白质的能力。作为模型功能蛋白，选择了β-葡萄糖苷酶。评估了明胶膜的拉伸性能，微观结构和结晶行为。

结果：我们的结果表明，膜结构可以在严格的条件下（75％相对湿度和37°C下保持47天）保持β-葡萄糖苷酶的活性。在对照膜和含1.8％β-葡萄糖苷酶的膜中，拉伸强度均随EG含量的增加而增加，而断裂伸长率则先增加，然后随时间降低。β-葡萄糖苷酶的存在对拉伸强度和断裂伸长率的影响可忽略不计。扫描电子显微镜（SEM）显示，随着EG含量增加或酶浓度降低，观察到了更致密的微观结构。

结论：总之，干膜是保持蛋白质稳定和处理的有前途的候选者。该配置方便且便宜，因此将来可用于蛋白质的存储和运输过程。