Institute for Technical Chemistry, Braunschweig University of Technology, 38106 Braunschweig, Germany.
Biomolecules. 2019 Oct 5;9(10):573. doi: 10.3390/biom9100573.
Therapeutics, proteins or drugs, can be encapsulated into multilayer systems prepared from chitosan (CS)/tripolyphosphat (TPP) nanogels and polyanions. Such multilayers can be built-up by Layer-by-Layer (LbL) deposition. For use as drug-releasing implant coating, these multilayers must meet high requirements in terms of stability. Therefore, photochemically crosslinkable chitosan arylazide (CS-Az) was synthesized and nanoparticles were generated by ionotropic gelation with TPP. The particles were characterized with regard to particle size and stability and were used to form the top-layer in multilayer films consisting of CS-TPP and three different polysaccharides as polyanions, namely alginate, chondroitin sulfate or hyaluronic acid, respectively. Subsequently, photo-crosslinking was performed by irradiation with UV light. The stability of these films was investigated under physiological conditions and the influence of the blocking layer on layer thickness was investigated by ellipsometry. Furthermore, the polyanion and the degree of acetylation (DA) of chitosan were identified as additional parameters that influence the film structure and stability. Multilayer systems blocked with the photo-crosslinked chitosan arylazide showed enhanced stability against degradation.
治疗剂，例如蛋白质或药物，可以被包裹在由壳聚糖（CS）/三聚磷酸（TPP）纳米凝胶和聚阴离子组成的多层系统中。这些多层结构可以通过层层（LbL）沉积技术构建。为了用作释放药物的植入物涂层，这些多层结构必须在稳定性方面满足高要求。因此，合成了光交联壳聚糖芳基叠氮化物（CS-Az），并通过与 TPP 的离子凝胶化生成纳米颗粒。对颗粒的粒径和稳定性进行了表征，并将其用于由 CS-TPP 和三种不同的多糖（分别为藻酸盐、硫酸软骨素或透明质酸）组成的多层薄膜的顶层。随后，通过紫外线照射进行光交联。在生理条件下研究了这些薄膜的稳定性，并通过椭圆偏振术研究了阻挡层对层厚度的影响。此外，聚阴离子和壳聚糖的乙酰化程度（DA）被确定为影响薄膜结构和稳定性的其他参数。用光交联的壳聚糖芳基叠氮化物封闭的多层系统显示出增强的稳定性，可抵抗降解。
