Improving pore interconnectivity in polymeric scaffolds for tissue engineering.
ABSTRACT A new scaffold fabrication technique aiming to enhance pore interconnectivity for tissue engineering has been developed. Medical grade poly(lactic acid) was utilized to generate scaffolds by a solvent-evaporating/particulate-leaching technique, using a new dual-porogen system. Water-soluble sodium chloride particles were used to control macro-pore size in the range 106-255 microm, while organic naphthalene was utilized as a porogen to increase pore interconnections. The three-dimensional (3D) morphology of the scaffolds manufactured with and without naphthalene was examined by optical coherence tomography and scanning electron microscopy. The mechanical properties of the scaffolds were characterized by compression tests. MG63 osteoblast cells were seeded in the scaffolds to study the cell attachment and viability evaluated by confocal microscopy. It was revealed that introducing naphthalene as the second porogen in the solvent-evaporating/particulate-leaching process resulted in improvement of the pore interconnectivity. Cells grew in both scaffolds fabricated with and without naphthalene. They exhibited strong green fluorescence when using a live/dead fluorescent dye kit, indicating that the naphthalene in the scaffold process did not affect cell viability.
Article: Monitoring sinew contraction during formation of tissue-engineered fibrin-based ligament constructs.[show abstract] [hide abstract]
ABSTRACT: The ability to study the gross morphological changes occurring during tissue formation is vital to producing tissue-engineered structures of clinically relevant dimensions in vitro. Here, we have used nondestructive methods of digital imaging and optical coherence tomography to monitor the early-stage formation and subsequent maturation of fibrin-based tissue-engineered ligament constructs. In addition, the effect of supplementation with essential promoters of collagen synthesis, ascorbic acid (AA) and proline (P), has been assessed. Contraction of the cell-seeded fibrin gel occurs unevenly within the first 5 days of culture around two fixed anchor points before forming a longitudinal ligament-like construct. AA+P supplementation accelerates gel contraction in the maturation phase of development, producing ligament-like constructs with a higher collagen content and distinct morphology to that of unsupplemented constructs. These studies highlight the importance of being able to control the methods of tissue formation and maturation in vitro to enable the production of tissue-engineered constructs with suitable replacement tissue characteristics for repair of clinical soft-tissue injuries.Tissue Engineering Part A 03/2012; 18(15-16):1596-607. · 4.64 Impact Factor