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In this paper, we introduce a new continuous production technique of calcium alginate fibers with a microfluidic platform similar to a spider in nature. We have used a poly(dimethylsiloxane) (PDMS) microfluidic device embedded capillary glass pipet as the apparatus for fiber generation. As a sample flow, we introduced a sodium alginate solution, and, as a sheath flow, a CaCl2 solution was introduced. The coaxial flows were generated at the intersection of both flows, and the sodium alginate was solidified to calcium alginate by diffusion of the Ca2+ ions during traveling through the outlet pipet. The diameter changes in the sample and sheath flow variations were examined, and the size of alginate fibers was well regulated by changing both flow rates. In addition, we have measured the elasticity of dried fibers. We evaluated the potential use of alginate fibers as a cell carrier by loading human fibroblasts during the "on the fly" fabrication process. From the LIVE/DEAD assay, cells survived well during the fiber fabrication process. In addition, we evaluate the capability of loading the therapeutic materials onto the alginate fibers by immobilized bovine serum albumin-fluorescein isothiocyanate in the fibers.

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This study presented the clinical characteristics, MRI features and postoperative results of 20 schwannomas in the arms of 13 patients. Twelve tumours had a positive Tinel’s sign, one caused weakness of the wrist and another in Guyon’s canal caused hypothenar muscle atrophy. Of the nine cases which underwent magnetic resonance imaging preoperatively, six were correctly diagnosed as schwannomas. All masses were excised using microsurgical techniques and two transient neurological complications occurred.

We developed microfluidic-based pure chitosan microfibers (approximately 1 meter long, 70-150 microm diameter) for liver tissue engineering applications. Despite the potential of the chitosan for creating bio-artificial liver chips, its major limitation is the inability to fabricate pure chitosan-based microstructures with controlled shapes because of the mechanical weakness of the pure chitosan. Previous studies have shown that chitosan micro/nanofibers can be fabricated by using chemicals and electrospinning techniques. However, there is no paper regarding pure chitosan-based microfibers in a microfluidic device. This paper suggests a unique method to fabricate pure chitosan microfibers without any chemical additive. We also analyzed the chemical, mechanical, and diffusion properties of pure chitosan microfibers. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectrometry and electron spectroscopy for chemical analysis (ESCA) were used to analyze the chemical composition of the synthesized chitosan microfibers. We measured the mechanical axial-force and diffusion coefficient in pure chitosan-based microfibers using fluorescence recovery after photobleaching (FRAP) techniques. Furthermore, to evaluate the capability of the microfibers for liver tissue formation, hepatoma HepG2 cells were seeded onto the chitosan microfibers. The functionality of these hepatic cells cultured on chitosan microfibers was analyzed by measuring albumin secretion and urea synthesis. Therefore, this pure chitosan-based microfiber chip could be a potentially useful method for liver tissue engineering applications.