Abstract: In recent years, the field of medicine has witnessed significant advancements, leading to an increased demand for drug slow release materials. As a result, drug slow release materials have emerged as a prominent area of research in the biomedical field. This is primarily due to their distinct advantages, including enhanced drug utilization and excellent biocompatibility. Fibrous drug sustained-release materials prepared using microfluidic spinning technology, offer a safe and stable menas of loading drug molecules. Fibers, serving as drug release carriers, possess several advantages including a large surface area and excellent biocompatibility. Therefore, this paper aims to prepared composite drug-carrying fibers with drug slow-release properties were using coaxial microfluidic spinning technology. The fibers are composed of natural polymer carriers, namely chitosan (CS) and sodium alginate (SA), which possess excellent biocompatibility. Additionally, a polyvinyl alcohol (PVA) solution is mixed with different ratios of polyvinyl alcohol (PVA) solution to serve as the spinning solution. The present study aims to investigate the drug release effect of two composite drug-carrying fibers, namely PVA/CS/AS (PCA) and PVA/SA/AS (PSA), using ampicillin sodium (AS) as a drug model. Additionally, the study aims to analyze the influence of the two types of natural polymer materials and their contents on the morphology and structure of the drug-carrying fibers, as well as their mechanical properties and drug release properties.
  The finding indicate that both PCA and PSA drug-carrying fibers exhibit consistent formability and possess a favorable morphological structure. The drug was effectively preserved during the fiber molding process, preventing the crystallization of drug molecules, which is essential for maintaining a drug efficacy and facilitating drug release. With the augmentation of polyvinyl alcohol (PVA) content, there was a gradual enhancement in, the fracture strength and elongation at break of both PCA and PSA composite fibers. Moreover, the fracture strength of PCA composite fibers wass found to be higher than that of PSA composite fibers, whereas the fracture elongation of PSA composite fibers was significantly greater than that of PCA composite fibers. In addition, both types of fibers exhibited a favorable slow-release effect on pharmaceutical substances, with the rate of cumulative drug release increasing proportionally to the PVA content present in the spinning solution. Among the various types of fibers studied, PCA composite fibers exhibited a rapid drug release profile, with a significant amount of drug being released within a short period of time. Specifically, and when the mass ratio of PVA to CS was 5:1, the cumulative release rate of the drug from PCA composite fibers rearch 60% within 180 minutes. On the other hand, PSA composite fibers demonstrated a sustained drug release over an extended period of time, with a release duration of 58 hours. When the mass ratio of PVA to SA was 64:1, the cumulative release rate of drug from PSA composite fibers reached 94.1%. Compared to PCA composite fibers, the release time and cumulative release rate of drugs are improved, which is suitable for the treatment of chronic diseases and achieves the purpose of long-term effective drug release. The disparity in drug release performance between the two fibers can be attributed to variations in the performance and structure of the drug carrier material itself. Bying utilizing the two drug-carrying composite fibers and various components within the spinning liquid, it is possible to develop a system for slow drug release that can be designed to meet the needs of different drug delivery patients. This demonstrates the wide-ranging potential for the application of slow and controlled drug release.

Key words: polyvinyl alcohol, chitosan, sodium alginate, drug-loaded fibers, sustained release of the drug, coaxial microfluidic spinning

摘要： 为了延长药物的可控释放时间，提高累计释放率，将生物相容性良好的天然高分子材料壳聚糖（CS）和海藻酸钠（SA）分别与聚乙烯醇（PVA）溶液混合作为纺丝液，通过同轴微流控纺丝技术制备具有药物缓释性能的复合载药纤维。以氨苄西林钠（AS）为药物模型，比较研究了PVA/CS/AS（PCA）和PVA/SA/AS（PSA）两种复合载药纤维的药物缓释效果，分析了两种天然高分子材料及其含量对载药纤维形貌结构、力学性能以及释药性能的影响。结果表明：PCA和PSA载药纤维均具有稳定的成型性和良好的形貌结构。PCA的断裂强度高于PSA复合纤维，而PSA的断裂伸长率远大于PCA复合纤维。此外，这两种纤维对药物均具有良好的缓释效果。其中，PCA复合纤维在短期内释药量大，当PVA与CS质量比为5∶1时，PCA复合纤维在180 min内药物的累计释放率最高为60%；而PSA复合纤维可以实现58 h的长时间药物释放，当PVA与SA质量比为64∶1时，PSA复合纤维药物累计释放率最高为94.1%，适合治疗慢性疾病，达到长期有效释药的目的。利用这两种载药复合纤维可设计适用于不同给药患者的药物缓释系统，展现出其在药物缓控释中的广阔应用前景。

关键词: 聚乙烯醇, 壳聚糖, 海藻酸钠, 载药纤维, 药物缓释, 同轴微流控纺丝