Measuring The Stiffness Of Hydrogels For Tissue Growth

Hydrogels (Figure 1) are extremely soft materials with high liquid content that have recently been used in various areas of biological and clinical research, e.g. from osteoporosis through tissue regeneration to hemorrhage control. Many hydrogels are considered as potential candidates for replacement or regeneration of many types of tissues or as growth substrates for other soft tissues in human body. Appropriate and effective application of hydrogels for specific cellular regeneration, growth and tissue replacement requires deep knowledge of their mechanical properties. For example, the structure and the mechanical properties of the growth substrate can act as a biomechanical modulator of cellular behavior and hence determine the function and quality of the growing cell [3]. It has also been found that the elasticity of the hydrogel substrate can significantly influence the homeostasis of tissues, which is crucial for efficient tissue regeneration.

Measurement of elastic – and in general term mechanical – properties of hydrogels used in biomedicine is therefore extremely important.

This application report presents the results of measurements of mechanical and creep properties of several types of soft polyacrylamide hydrogels using a novel nanoindentation device for bioindentation called Bioindenter.