Bannerman A Dawn, Li Xinyi, Wan Wankei
Graduate Program in Biomedical Engineering, University of Western Ontario, London, Ontario N6A 5B9, Canada.
University of Western Ontario, Department of Chemical and Biochemical Engineering, Graduate Program in Biomedical Engineering, London, Ontario N6A 5B9, Canada.
Acta Biomater. 2017 Aug;58:376-385. doi: 10.1016/j.actbio.2017.05.018. Epub 2017 May 10.
Polymeric materials that contain magnetic nanoparticles are extremely useful in many applications including as multifunctional drug carriers, imaging contrast agents, or scaffold material. There is a need for biomaterials with appropriate chemical, mechanical, and magnetic properties that also have the ability to degrade or dissolve over time so they can be eliminated from the body following use. In this work, we explore the use of iron oxide nanoparticle (IONP) formation in poly(vinyl alcohol) (PVA) as a crosslinking method in conjunction with physical crosslinking achieved using low temperature thermal cycling (LTTC). PVA-IONP hydrogels were fabricated and characterized. IONPs contribute to the crosslinking of the PVA-IONP material, and their subsequent removal reduces crosslinking, and therefore stability, of the material, allowing dissolution to occur. Dissolution studies were performed on PVA-IONP hydrogels and dissolution was compared for films in solutions of varying pH, in the presence of iron chelating agents, and in simulated physiological and tumor conditions in cell culture media. Iron release, mass loss, and mechanical testing data was collected. This work demonstrates the ability of this biomaterial to 'degrade' over time, which may be very advantageous for applications such as drug delivery. This importance of this work extends to other areas such as the use of stimuli-responsive hydrogels.
This manuscript explores the stability of an iron oxide nanoparticle (IONP)-containing, physically crosslinked poly(vinyl alcohol) (PVA) hydrogel. The PVA-IONP hydrogel's stability is imparted through crosslinks created through a low temperature thermal cycling process and through the IONPs. Subsequent IONP removal reduces crosslinks so material dissolution can occur, resulting in a 'degradable' and multifunctional biomaterial. PVA-IONP films were fabricated, characterized and evaluated in terms of dissolution in solutions of varying pH and in the presence of chelating agents. Iron release, mass loss, and mechanical testing data demonstrate the ability of the PVA-IONP biomaterial to 'degrade' over time. This degradability has not yet been demonstrated for crosslinked PVA hydrogels. These results are relevant to the development of degradable multifunctional drug carriers, image contrast agents, or magnetic scaffold materials.
含有磁性纳米颗粒的聚合材料在许多应用中极为有用，包括作为多功能药物载体、成像造影剂或支架材料。需要具有适当化学、机械和磁性特性且能够随时间降解或溶解的生物材料，以便在使用后能从体内清除。在这项工作中，我们探索在聚乙烯醇（PVA）中形成氧化铁纳米颗粒（IONP）作为一种交联方法，并结合使用低温热循环（LTTC）实现的物理交联。制备并表征了PVA - IONP水凝胶。IONP有助于PVA - IONP材料的交联，其随后的去除会降低材料的交联度，进而降低材料的稳定性，使溶解得以发生。对PVA - IONP水凝胶进行了溶解研究，并比较了薄膜在不同pH值溶液、存在铁螯合剂的溶液以及细胞培养基模拟生理和肿瘤条件下的溶解情况。收集了铁释放、质量损失和力学测试数据。这项工作证明了这种生物材料随时间“降解”的能力，这对于药物递送等应用可能非常有利。这项工作的重要性扩展到其他领域，如刺激响应水凝胶的使用。
本手稿探讨了含氧化铁纳米颗粒（IONP）的物理交联聚乙烯醇（PVA）水凝胶的稳定性。PVA - IONP水凝胶的稳定性通过低温热循环过程和IONP形成的交联赋予。随后去除IONP会减少交联，从而使材料能够溶解，产生一种“可降解”的多功能生物材料。制备了PVA - IONP薄膜，对其进行了表征，并评估了其在不同pH值溶液和存在螯合剂情况下的溶解性。铁释放、质量损失和力学测试数据证明了PVA - IONP生物材料随时间“降解”的能力。这种可降解性尚未在交联PVA水凝胶中得到证明。这些结果与可降解多功能药物载体、图像造影剂或磁性支架材料的开发相关。
