Papers by Keyword: Aligned

Abstract: Tendon repair remains a formidable challenge in clinic, due to its limited function in long-term recovery. Decellularized native tendon extracellular matrix (ECM), which contains specific bioactive factors and a large number of collagen fibers, seeded with bone marrow-derived stem cells (BMSCs) has been found to promote tendon neogenesis. However, the effect of arrangements of natural collagen fibers on the differentiation of BMSCs remains unclear. Here, we prepared aligned collagen fiber scaffolds from rat tail tendon ECM to investigate the effect of collagen arrangements on the morphology, proliferation and differentiation of rat BMSCs in vitro. It was found that BMSCs were elongated and aligned along the collagen fibers on the aligned collagen fibers. Furthermore, the aligned collagen scaffolds significantly enhanced the expression of tenocyte markers TNMD and THBS4. The results indicated that aligned collagen scaffolds could induce the tenogenesis of BMSCs, which would provide an alternative approach for tendon tissue engineering.

Abstract: Electrospinning has been applied to prepare uniaxially aligned nanofibers made of organic polymers, ceramics, and polymer/ceramic composites. The highly aligned PAN nanofiber was successfully fabricated by the simple rapid method for preparing parallel micropipette electrodes. The effect of collect distance on the degree of aligned nanofibers and diameter distribution as well as the variation trend was explored and reseached.

Abstract: Electrospinning has emerged as a very attractive approach to the fabrication of nanofibers. In electrospinning process, the ability to control the alignment and arrangement of fibers is critical to achieve the designed functions. In this paper, we had successfully fabricated highly aligned PAN nanofibers by the method of parallel electrode electrospinning. The study revealed the optimum weight ratio of PAN polymer solution for aligned nanofibers was 8%-12%. Results show that the increasing of weight ratio of polymer solution can enhance the parallelism and uniformity of electrospun fiber diameter distribution.

Abstract: Preparation of uniaxially aligned nanofibers by electrospinning has been a new research hot spot in recent years. Well-aligned polysulfonamide (PSA) nanofibers with the diameter of 200nm were successfully prepared by magnetic electrospinning with the distance between the two magnets of 8cm. The key to the success of this method was the use of a collector composed of two permanent magnets to suffer an applied magnetic field. And the mechanism of magnetic electrospinning was also discussed in detail.

Abstract: Highly aligned carbon nanotube arrays (HACNTAs) were synthesized on a stainless steel substrate from a methanol solution of Co(Ⅲ) acetylacetonate by the one-step liquid-phase synthesis, and effects of H2O addition on the HACNTA growth were examined. The growth rate was considerably accelerated, and the lifetime of the catalysts was prolonged by addition of a small amount of H2O. HACNTAs with over 400 m thickness were formed on the side surfaces of the substrate by resistance-heating for one hour. This suggests that the added H2O removes deposited amorphous carbons from the catalyst surfaces and consequently accelerates the growth rate.

Abstract: Vertically aligned carbon nanotubes (CNTs) were grown on a stainless steel substrate (SUS304) by resistance-heating method in alcohols containing homogeneously dissolved cobaltocene Co(C5H5)2 as a catalyst source. Straight-chain primary alcohols, 1,2-ethanediol and cyclohexanol were used as carbon sources to examine the effects of the molecular structures on the morphology of the aligned CNTs. Methanol brought the best purity and alignment of CNTs of all the alcohols. The CNTs from 1,2-ethanediol was worse in the purity than those from ethanol with the same number of carbon atoms. The CNTs from cyclohexanol had a better purity than those from 1-hexanol. Distinctive features of this method are simple, low cost and a one-step process involving none of vacuum processes and catalyst preparation processes.