Chen Ming, Patra Prabir K, Warner Steven B, Bhowmick Sankha
Biomedical Engineering and Biotechnology Program, University of Massachusetts-Dartmouth, North Dartmouth, Massachusetts, USA.
Tissue Eng. 2007 Mar;13(3):579-87. doi: 10.1089/ten.2006.0205.
The goal of the current study was to find the quantitative relationship between electrospun polycaprolactone scaffold fiber diameter and NIH 3T3 fibroblast adhesion and growth kinetics. By varying 3 important process parameters--solution concentration, voltage, and collector screen distance--different average fiber diameters ranging from 117 to 1,647 nm were obtained. Although 117 nm represented the lowest possible fiber diameter obtainable, these fibers had beads in them. An increase in fiber diameter to 428 nm led to uniform fibers without any beads. Fiber distribution pattern was a single mode for all the scaffolds except at the largest-diameter end. The diameter distribution changed from single to bimodal at 1,647 nm, suggesting some instability in the process. It was found that cell adhesion and growth kinetics are significantly affected as a function of fiber diameter. Beaded scaffolds offered the lowest cell adhesion and minimal growth kinetics despite having the lowest average fiber diameter. When uniform fibers were formed and the average fiber was in the nanofiber range (428-1051 nm), cell adhesion and growth kinetics decreased as a function of increasing fiber diameter. Cell adhesion kinetics remained invariant when the average fiber diameter was in the micron range (1,647 nm), whereas cell-growth kinetics were slightly greater than with 900 nm scaffolds. We propose that the uniformness of fibers and the average fiber diameter may play an important role in modulating cellular attachment and proliferation in electrospun tissue engineering scaffolds.
本研究的目的是找出电纺聚己内酯支架纤维直径与NIH 3T3成纤维细胞黏附及生长动力学之间的定量关系。通过改变3个重要的工艺参数——溶液浓度、电压和收集器筛网距离，获得了117至1647 nm范围内不同的平均纤维直径。虽然117 nm代表可获得的最低纤维直径，但这些纤维中有珠子。纤维直径增加到428 nm时，得到了没有任何珠子的均匀纤维。除了最大直径端外，所有支架的纤维分布模式均为单峰。在1647 nm处，直径分布从单峰变为双峰，表明该过程存在一些不稳定性。研究发现，细胞黏附及生长动力学作为纤维直径的函数受到显著影响。尽管平均纤维直径最低，但有珠子的支架提供的细胞黏附力最低，生长动力学最小。当形成均匀纤维且平均纤维处于纳米纤维范围内（428 - 1051 nm）时，细胞黏附及生长动力学随纤维直径增加而降低。当平均纤维直径处于微米范围内（1647 nm）时，细胞黏附动力学保持不变，而细胞生长动力学略高于900 nm支架。我们认为，纤维的均匀性和平均纤维直径可能在调节电纺组织工程支架中的细胞附着和增殖方面发挥重要作用。
