Wimpenny I, Lahteenkorva K, Suokas E, Ashammakhi N, Yang Y
a Institute of Science and Technology in Medicine, Keele University, The Guy Hilton Research Centre , Thornburrow Drive, Hartshill , Stoke-on-Trent , Staffordshire , ST4 7QB , UK.
J Biomater Sci Polym Ed. 2012;23(14):1863-77. doi: 10.1163/156856211X598238. Epub 2012 May 11.
Intensive research has demonstrated the clear biological potential of electrospun nanofibers for tissue regeneration and repair. However, nanofibers alone have limited mechanical properties. In this study we took poly(L-lactide-co-D-lactide) (PLDLA)-based 3D objects, one existing medical device (interference screws) and one medical device model (discs) as examples to form composites through coating their surface with electrospun PLDLA nanofibers. We specifically investigated the effects of electrospinning parameters on the improvement of adhesion of the electrospun nanofibers to the PLDLA-based substrates. To reveal the adhesion mechanisms, a novel peel test protocol was developed for the characterization of the adhesion and delamination phenomenon of the nanofibers deposited to substrates. The effect of incubation of the composites under physiological conditions on the adhesion of the nanofibers has also been studied. It was revealed that reduction of the working distance to 10 cm resulted in deposition of residual solvent during electrospinning of nanofibers onto the substrate, causing fiber-fiber bonding. Delamination of this coating occurred between the whole nanofiber layer and substrate, at low stress. Fibers deposited at 15 cm working distance were of smaller diameter and no residual solvent was observed during deposition. Delamination occurred between nanofiber layers, which peeled off under greater stress. This study represents a novel method for the alteration of nanofiber adhesion to substrates, and quantification of the change in the adhesion state, which has potential applications to develop better medical devices for orthopedic tissue repair and regeneration.
深入研究已证明电纺纳米纤维在组织再生和修复方面具有明确的生物学潜力。然而，仅纳米纤维的机械性能有限。在本研究中，我们以聚（L-丙交酯-co-D-丙交酯）（PLDLA）基三维物体、一种现有的医疗器械（干涉螺钉）和一种医疗器械模型（椎间盘）为例，通过在其表面涂覆电纺PLDLA纳米纤维来形成复合材料。我们专门研究了电纺参数对提高电纺纳米纤维与PLDLA基基材附着力的影响。为了揭示粘附机制，开发了一种新颖的剥离试验方案，用于表征沉积在基材上的纳米纤维的粘附和分层现象。还研究了复合材料在生理条件下孵育对纳米纤维粘附的影响。结果表明，将工作距离缩短至10 cm会导致在纳米纤维电纺到基材上的过程中残留溶剂沉积，从而导致纤维与纤维之间的粘结。这种涂层在较低应力下会在整个纳米纤维层与基材之间发生分层。在15 cm工作距离下沉积的纤维直径较小，沉积过程中未观察到残留溶剂。分层发生在纳米纤维层之间，在较大应力下会剥落。本研究提出了一种改变纳米纤维与基材粘附力以及量化粘附状态变化的新方法，这对于开发用于骨科组织修复和再生的更好的医疗器械具有潜在应用价值。
