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Thermoplastic resins (linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), and polypropylene (PP)) reinforced by different content ratios of raw agave fibers were prepared and characterized in terms of their mechanical, thermal, and chemical properties as well as their morphology. The morphological properties of agave fibers and films were characterized by scanning electron microscopy and the variations in chemical interactions between the filler and matrix materials were studied using Fourier-transform infrared spectroscopy. No significant chemical interaction between the filler and matrix was observed. Melting point and crystallinity of the composites were evaluated for the effect of agave fiber on thermal properties of the composites, and modulus and yield strength parameters were inspected for mechanical analysis. While addition of natural fillers did not affect the overall thermal properties of the composite materials, elastic modulus and yielding stress exhibited direct correlation to the filler content and increased as the fiber content was increased. The highest elastic moduli were achieved with 20 wt % agave fiber for all the three composites. The values were increased by 319.3%, 69.2%, and 57.2%, for LLDPE, HDPE, and PP, respectively. The optimum yield stresses were achieved with 20 wt % fiber for LLDPE increasing by 84.2% and with 30 wt % for both HDPE and PP, increasing by 52% and 12.3% respectively. 

Abstract Mimicking microvascular tissue microenvironment in vitro calls for a cytocompatible technique of manufacturing biocompatible hollow microfibers suitable for cell‐encapsulation/seeding in and around them. The techniques reported to date either have a limit on the microfiber dimensions or undergo a complex manufacturing process. Here, a microfluidic‐based method for cell seeding inside alginate hollow microfibers is designed whereby mouse astrocytes (C8‐D1A) are passively seeded on the inner surface of these hollow microfibers. Collagen I and poly‐d‐lysine, as cell attachment additives, are tested to assess cell adhesion and viability; the results are compared with nonadditive‐based hollow microfibers (BARE). The BARE furnishes better cell attachment and higher cell viability immediately after manufacturing, and an increasing trend in the cell viability is observed between Day 0 and Day 2. Swelling analysis using percentage initial weight and width is performed on BARE microfibers furnishing a maximum of 124.1% and 106.1%, respectively. Degradation analysis using weight observed a 62% loss after 3 days, with 46% occurring in the first 12 h. In the frequency sweep test performed, the storage modulus (G′) remains comparatively higher than the loss modulus (G″) in the frequency range 0–20 Hz, indicating high elastic behavior of the hollow microfibers. 

Abstract Engineering conductive 3D cell scaffoldings offer advantages toward the creation of physiologically relevant platforms with integrated real‐time sensing capabilities. Dopaminergic neural cells are encapsulated into graphene‐laden alginate microfibers using a microfluidic approach, which is unmatched for creating highly‐tunable microfibers. Incorporating graphene increases the conductivity of the alginate microfibers by 148%, creating a similar conductivity to native brain tissue. The cell encapsulation procedure has an efficiency of 50%, and of those cells, ≈30% remain for the entire 6‐day observation period. To understand how the microfluidic encapsulation affects cell genetics, tyrosine hydroxylase, tubulin beta 3 class 3, interleukin 1 beta, and tumor necrosis factor alfa are analyzed primarily with real‐time reverse transcription‐quantitative polymerase chain reaction and secondarily with enzyme‐linked immunosorbent assay, immediately after manufacturing, after encapsulation in polymer matrix for 6 days, and after encapsulation in the graphene‐polymer composite for 6 days. Preliminary data shows that the manufacturing process and combination with alginate matrix affect the expression of the studied genes immediately after manufacturing. In addition, the introduction of graphene further changes gene expressions. Long‐term encapsulation of neural cells in alginate and 6‐day exposure to graphene also leads to changes in gene expressions.