Nano-indentation of epoxy hydro gels for soft tissue applications

Nano-indentation characterization studies on epoxy hydro gels used for soft tissue applications are conducted using atomic force microscope (AFM). Two kinds of hydro gels: (a) plain epoxy hydro gels, and (b) epoxy hydro gels reinforced with three-dimensional polyurethane fiber pattern are considered in this study. The three-dimensional fiber pattern is generated using rapid robo-casting technique. Again these two hydro gel types are tested under five different conditions: (a) dry gel, (b) saturated with certain percentage of water, (c) saturated with 100% water, (d) 100% partially immersed in water, and (e) 100% fully immersed in water. Preliminary results obtained on plain epoxy hydro gels show that the saturated conditions decrease Young's modulus values by 15%.