Aim: To improve the long-term storage stability of a bioactive protein and the subsequent colon-targeted release, a double-layer chitosan (CS)-based particle was developed.

Methods: To form the double-layer CS-based particle, the second layer was crosslinked onto the single-layer bovine serum albumin (BSA)-loaded CS-based particle. The structure and properties of particles were further investigated.

Results: With the second layer, the double-layer particles became more compact, which was important for the inhibition of bioactive protein leakage during storage through strong electrostatic interactions and swelling of the hydrogels. After 30 d of storage, there was only 43.74–49.32% BSA leakage from the C15-TPP/C15-HMP double-layer particles. Moreover, the BSA release in subsequent colon-targeted delivery after storage was 44.02–48.59%.

Conclusions: With double-layer shielding and a more compact arrangement, it was possible to reduce bioactive protein leakage over long periods storage and achieve subsequent colon-targeted delivery.

目的：为了提高生物活性蛋白的长期存储稳定性以及随后的结肠靶向释放，开发了一种基于壳聚糖（CS）的双层颗粒。

方法：为了形成双层CS基颗粒，将第二层交联到负载单层牛血清白蛋白（BSA）的CS基颗粒上。进一步研究了颗粒的结构和性质。

结果：在第二层中，双层颗粒变得更致密，这对于通过强静电相互作用和水凝胶溶胀来抑制储存过程中生物活性蛋白的泄漏非常重要。储存30天后，从C15-TPP / C15-HMP双层颗粒泄漏的BSA仅43.74–49.32％。此外，在储存后随后的结肠靶向递送中，BSA的释放为44.02–48.59％。

结论：利用双层屏蔽和更紧凑的布置，可以减少长期保存时生物活性蛋白的渗漏并实现随后的结肠靶向递送。