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Novel porous scaffolds were fabricated using biodegradable polylactide/chitosan blends. A combinational technique involving solvent-extracting, liquid-solid separation, and freeze-drying paths were employed. The processing parameters were optimized in order to produce desired porous scaffolds and thus obtained scaffolds showed well distributed and interconnected porous structures with controllable porosities varying from around 50-85% and regulative pore sizes being distributed within a region between 2 and 190 microm. These scaffolds exhibited remarkably improved hydrophilicity based on the measurements for their swelling index. The results obtained from in vitro incubation of scaffolds in phosphate buffered saline solutions at 37 degrees C during various periods up to 10 weeks indicated that chitosan component inside the scaffolds, on the one hand, effectively buffered the acidic degradation products of polylactide/chitosan scaffolds and on the other hand, the degradation of the scaffolds was also conspicuously delayed. These porous scaffolds maintained well-defined compressive mechanical properties and by well-blending polylactide with chitosan component, improved toughness on the resultant porous scaffolds was also observed.

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Polycaprolactone (PCL) and chitosan were blended to fabricate porous scaffolds for tissue-engineering applications by employing a concentrated acetic acid solution as solvent and salt particles as porogen. These scaffolds showed well-controlled and interconnected porous structures. The pore size and porosity of the scaffolds could be effectively modulated by selecting appropriate amounts and sizes of porogen. The results obtained from compressive mechanical measurements indicated that PCL/chitosan could basically retain their strength in their dry state compared to individual components. In a hydrated state, their compressive stress and modulus could be still well maintained even though the weight ratio of chitosan reached around 50 wt%.

DL‐lactic acid was grafted onto chitosan to produce poly(chitosan‐g‐DL‐lactic acid)(PCLA) without using a catalyst. These PCLAs were then spun into filaments and further fabricated into fibrous mesh scaffolds using an improved wet‐spinning technique. The diameter of filaments in different scaffolds could vary from a few micrometers to several tens of micrometers. The scaffolds exhibited various pore sizes ranging from about 20 µm to more than 200 µm and different porosities up to 80%. The several main processing conditions were optimized for obtaining the desired scaffolds with well‐controlled structures. The tensile and compressive mechanical properties of the mesh scaffolds in both dry and hydrated states were mainly examined. Significantly improved tensile strength and modulus, enhanced compressive modulus, and stress as well as the dimensional stability for these mesh scaffolds in their hydrated state were observed. Copyright © 2007 John Wiley & Sons, Ltd.

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