Study of the influence of β-radiation on the properties and mineralization of different starch-based biomaterials

In this work, the effects of β-radiation are assessed, for the first time, on starch-based biodegradable polymers, with the aim of using it as an alternative sterilization process to the previously studied sterilization methods. Different doses of radiation were used in order to investigate the possibility of using this sterilization technique as a treatment to tailor the surface and bulk properties (namely mechanical) of these polymers. The as-treated substrates were characterized by water-uptake measurements and contact angle (θ) measurements. The mechanical properties of the materials were characterized by tensile tests by means of ultimate tensile strength (UTS) and strain at break (εr). The fracture of the surfaces was observed by scanning electron microscopy (SEM). Dynamic mechanical analysis (DMA) was also used to characterize the viscolelastic behavior of the irradiated materials. The main effect of sterilization with β-radiation over the starch-based polymers seems to be a surface modification by an increase of the hydrophilicity. Nevertheless, because -radiation did not significantly affect the mechanical properties, it can be regarded as an effective way of modifying the surface for applications were more hydrophilic surfaces are desirable.