Abstract:
Electrospinning is a widely employed manufacturing platform for tissue engineering applications because it produces structures that closely mimic the extracellular matrix. Herein, we demonstrate the potential of poly(vinyl alcohol) (PVA) electrospun nanofibers as scaffolds for tissue engineering. Nanofibers were created by needleless direct current electrospinning from PVA with two different degrees of hydrolysis (DH), namely 98% and 99% and subsequently heat treated at 180 °C for up to 16 h to render them insoluble in aqueous environments without the use of toxic cross-linking agents. Despite the small differences in the PVA chemical structure, the changes in the material properties were substantial. The higher degree of hydrolysis resulted in non-woven supports with thinner fibres (285 ± 81 nm c.f. 399 ± 153 nm) that were mechanically stronger by 62% (±11%) and almost twice as more crystalline than those from 98% hydrolysed PVA. Although prolonged heat treatment (16 h) did not influence fibre morphology, it reduced the crystallinity and tensile strength for both sets of materials. All samples demonstrated a lack or very low degree of haemolysis (<5%), and there were no notable changes in their anticoagulant activity (≤3%). Thrombus formation, on the other hand, increased by 82% (±18%) for the 98% hydrolysed samples and by 71% (±10%) for the 99% hydrolysed samples, with heat treatment up to 16 h, as a direct consequence of the preservation of the fibrous morphology. 3T3 mouse fibroblasts showed the best proliferation on scaffolds that were thermally stabilised for 4 and 8 h. Overall these scaffolds show potential as \'greener\' alternatives to other electrospun tissue engineering materials, especially in cases where they may be used as delivery vectors for heat tolerant additives.
摘要:
静电纺丝是用于组织工程应用的广泛采用的制造平台,因为其产生紧密模拟细胞外基质的结构。在这里,我们证明了聚乙烯醇(PVA)电纺纳米纤维作为组织工程支架的潜力。纳米纤维是由具有两种不同水解度(DH)的PVA通过无针直流电纺产生的,即98%和99%,随后在180°C下热处理长达16小时,以使其不溶于水性环境,而无需使用有毒交联剂。尽管PVA化学结构存在微小差异,材料性能的变化是巨大的。较高的水解度导致具有较薄纤维(285±81nmc.f.399±153nm)的非织造载体,其机械强度为62%(±11%),并且比98%水解的PVA的那些结晶几乎多两倍。尽管长时间的热处理(16小时)不会影响纤维形态,它降低了两组材料的结晶度和拉伸强度。所有样本均表现出缺乏或非常低的溶血程度(<5%),抗凝活性无明显变化(≤3%)。血栓形成,另一方面,98%水解样品增加82%(±18%),99%水解样品增加71%(±10%),热处理长达16小时,作为纤维形态保存的直接结果。3T3小鼠成纤维细胞在热稳定4和8小时的支架上显示出最佳的增殖。总体而言,这些支架显示出作为其他电纺组织工程材料的“绿色”替代品的潜力,特别是在它们可以用作耐热添加剂的递送载体的情况下。