Regenerative medicine shows promise as a field that can solve complex diseases, especially when natural tissue regeneration does not occur. A key aspect of regenerative therapies is matching the stiffness of the implanted cells to the stiffness of mature tissues. Mechanical measurements have helped to show how regenerative therapies may have viable outcomes, and can be used to determine if a given strategy is effective.
Tuned biomaterials have shown promise to be used for regenerative medicine to mimic living tissue, and the structure of the materials combined with the mechanical properties are key to ensuring that they will be functional . Bartlett, et al.  analyzed the compressive viscoelastic characteristics of different sections of spinal cord and brain tissue, and found different regions to have different properties. These different characteristics were then matched with different biomaterials used in regenerative medicine to offer guidance on matching biomaterials to the region targeted in a regenerative therapy. In another study , the authors developed a new regenerative repair patch for intervertebral discs, which are known to require significant compressive loading ability. The authors did significant mechanical characterization of their new material to demonstrate its potential effectiveness as a treatment option. In another study, researchers developed a new biomaterial with applications for regenerative medicine to enhance cell-cell communication that used a porous material . As the authors understood the importance of mechanics, they also measured the mechanical properties of the new material compared with previous materials they developed to ensure that the porous structure did not change the mechanical properties for the cells.
Cartilage has key mechanical functions in the body, and it is a primary target for replacement when it is subject to disease. Several products have been introduced for replacing cartilage, and new work has sought to produce regenerative tissues as the replacement tissue. A key aspect of developing viable cartilage tissues for implantation has been the introduction of mechanical loading in the form of hydrostatic pressures, compressive loading, and ultrasound . Furthermore, mechanical testing has been suggested as a functional readout for cartilage for tissue engineering. By using nanoindentation, the researchers were also able to determine the local effects of stiffness changes on the cartilage samples [2, figure], which can prove valuable when developing new treatments for regenerative medicine. Mechanical analysis of cartilage replacements after implant can also explain how effective the therapy is. Franke, et al. [new 3] investigated the mechanical properties of healthy and repair cartilage tissues and found a more comprehensive result of the limitations of repair based on the mechanical data compared to the results solely based on histology.
Spheroids are aggregates of cells that serve many purposes, including as a potential way to create 3D tissues for regenerative medicine. One study created spheroids from stem cells as a potential treatment for spiral ganglion neurons and used the mechanical properties as a marker for the suitability for transplantation . The mechanical measurements were performed with the Piuma nanoindenter, and they showed a change in stiffness over time and with different wellplates, and the authors were able to characterize the spheroids compared with native mouse brain tissue. In another study, the authors generated spheroids that matured over time from pre-vascularized spheroids to spheroids with vascular networks . Mechanical studies of the spheroids showed a change in the mechanical properties over time and provided valuable feedback about how structural changes were occurring in the new spheroids.
Optics11 Life Instruments
Optics11 Life nanoindenters offer mechanical characterization that can explore the micro-mechanical properties of cells, tissues, and biomaterials. These unique nanoindenters can be used in liquid environments on soft materials to provide accurate and precise measurements. The nanoindenters can be directly integrated into microscopy and other processes to offer a complete view when developing new regenerative medicine methods.