Microwave processing of starch-based porous structures for tissue engineering scaffolds

A novel microwave (MW) processing technique was used to produce biodegradable scaffolds for tissue engineering from different types of starch-based polymers. Potato, sweet potato, corn starch, and nonisolated amaranth and quinoa starch were used to produce porous structures. Water and glycerol were used as plasticizers for the different types of starch. Characterization of the pore morphology of the scaffolds was carried out with scanning electron microscopy. Three-dimensional structures with variable porosity and pore size distribution were obtained with the MW foaming technique. The amount of remaining water in the scaffolds and their corresponding densities showed important variations among the different types of starch. Compressive mechanical properties were assessed by indentation tests, and a strong dependence of the indentation stress on the average pore size was found. Studies in simulated body fluid were used to assess the in vitro bioactivity, degradability, and surface topology evolution in the scaffolds.