A simple, novel method to produce porous 2,3-dialdehydecellulose (DAC) membranes as a potential tissue-engineering scaffold has been developed from methylolcellulose by the simultaneous water-induced phase separation and sodium chloride salt leaching techniques, followed by oxidation with sodium periodate in water. Membrane pores increased in size with increasing weight or particle size of the sodium chloride salt. The porosity of the membrane was not affected by the salt particle size, but it increased with an increase in the salt weight to 60%. At higher salt weight percentages, no significant change in the membrane porosity was observed. The oxidation step had no effect on the membrane porosity or pore size. All membranes with a porosity value ranging between 87 and 93% showed interconnected porous structures. The use of these membranes as a potential tissue-engineering scaffold was evaluated with the use of human neonatal skin fibroblast cells. Confocal microscopy showed cell attachment and spreading on these membranes. Immunohistochemical tests revealed the presence of collagen type III and fibronectin, indicating that the cells were viable and formed the extracellular matrix. In conclusion, the DAC membrane supports cell adhesion and proliferation and hence shows potential to be used as a tissue-engineering scaffold.

Porous 2,3-dialdehydecellulose (2,3-DAC) membranes were investigated for use as a synthetic scaffold for engineering vocal fold-like tissues. Two criteria of this application are (i) the viscoelastic shear properties of the scaffold should be controllable in the range of vocal fold tissues and (ii) scaffolds should remain biomechanically stable to withstand vibrational stresses in a bioreactor. Porous 2,3-DAC membranes were fabricated from methylolcellulose by water-induced cellulose regeneration, with or without sodium chloride leaching, followed by periodate oxidation. They were freeze-dried and ethylene oxide-sterilized. Different degrees of oxidation were obtained on reacting with sodium metaperiodate for different time points. Rheological studies were performed to investigate the effect of freeze-drying, porosity, degree of oxidation, sterilization, and incubation time on elastic and viscous shear moduli, G' and G'', respectively, for frequencies 0.01-10 Hz. Freeze drying increased G' and G'', while increased porosity and degree of oxidation reduced G' and G''. Sterilization had no effect on viscoelasticity. When incubated in Dulbecco's minimum essential medium at 37 degrees C, membranes with 6-7% and 19-20% oxidation disintegrated after 7 and 3 days, respectively, while membranes with 3-4% oxidation showed little viscoelastic change over a period of 42 days. The upper frequency limit of rheologic measurement was a limitation of the study and should be addressed in future investigations.