六臂共聚物聚己内酯-聚乙二醇的蛋白质递药纳米系统用于长效持续释放。

BACKGROUND: To address the issue of delivery of proteins, a six-arm copolymer, six-arm poly (ε-caprolactone)-poly(ethylene glycol) (6S-PCL-PEG), was synthesized by a simple two-step reaction. Thereafter, the application of 6S-PCL-PEG as a protein carrier was evaluated. MATERIALS AND METHODS: A six-arm copolymer, six-arm poly(ε-caprolactone) (6S-PCL), was synthesized by ring-opening polymerization, with stannous octoate as a catalyst and inositol as an initiator. Then, poly(ethylene glycol) (PEG) was linked with 6S-PCL by oxalyl chloride to obtain 6S-PCL-PEG. Hydrogen-1 nuclear magnetic resonance spectrum, Fourier-transform infrared spectroscopy, and gel-permeation chromatography were conducted to identify the structure of 6S-PCL-PEG. The biocompatibility of the 6S-PCL-PEG was evaluated by a cell counting kit-8 assay. Polymeric nanoparticles (NPs) were prepared by a water-in-oil-in-water double emulsion (W/O/W) solvent evaporation method. The size distribution and zeta potential of NPs were determined by dynamic light scattering. Transmission electron microscopy was used to observe the morphology of NPs. Drug-loading capacity, encapsulation efficiency, and the release behavior of ovalbumin (OVA)-loading NPs were tested by the bicinchoninic acid assay kit. The stability and activity of OVA released from NPs were detected and the uptake of NPs was evaluated by NIH-3T3 cells. RESULTS: All results indicated the successful synthesis of amphiphilic copolymer 6S-PCL-PEG, which possessed excellent biocompatibility and could formulate NPs easily. High drug-loading capacity and encapsulation efficiency of protein NPs were observed. In vitro, OVA was released slowly and the bioactivity of OVA was maintained for over 28 days. CONCLUSION: 6S-PCL-PEG NPs prepared in this study show promising potential for use as a protein carrier.

背景：为了解决蛋白质的递送问题，通过简单的两步反应合成了一种六臂共聚物，六臂聚（ε-己内酯）-聚（乙二醇）（6S-PCL-PEG）。此后，评估了 6S-PCL-PEG 作为蛋白质载体的应用。

材料与方法：通过开环聚合，以辛酸亚锡为催化剂，肌醇为引发剂，合成了六臂共聚物六臂聚（ε-己内酯）（6S-PCL）。然后，用草酰氯将聚乙二醇（PEG）与 6S-PCL 连接，得到 6S-PCL-PEG。通过氢-1 核磁共振谱、傅里叶变换红外光谱和凝胶渗透色谱对 6S-PCL-PEG 的结构进行了鉴定。通过细胞计数试剂盒-8 测定法评估了 6S-PCL-PEG 的生物相容性。通过水包油包水（W/O/W）双乳液溶剂蒸发法制备了聚合物纳米颗粒（NPs）。通过动态光散射法测定 NPs 的粒径分布和 Zeta 电位。透射电子显微镜观察 NPs 的形态。通过双缩脲法测定卵清蛋白（OVA）载药 NPs 的载药量、包封率和释放行为。通过 NIH-3T3 细胞检测 NPs 释放的 OVA 的稳定性和活性以及 NPs 的摄取。

结果：所有结果均表明成功合成了两亲性共聚物 6S-PCL-PEG，该共聚物具有良好的生物相容性，易于制备 NPs。观察到蛋白质 NPs 具有较高的载药量和包封效率。体外，OVA 缓慢释放，OVA 的生物活性可维持 28 天以上。