Suitability of developed composite materials for meniscal replacement: Mechanical, friction and wear evaluation

Highly flexible elastomer microfluidic chip for single cell manipulation

New materials and fabrication technologies have significantly boosted the development of lab-on-a-chip technologies and functionalities. In this work, we developed a highly flexible elastomer microfluidic chip with a microchannel with a minimum width of ∼5 μm manufactured by imprinting onto an SU-8 template. We found that the deformation induced in the microstructures by manual stretching of the chip is higher than that for the chip itself, which we attribute to the stress concentration of microstructures. Here, we demonstrate that the elastomer enables the manipulation of single cells, such as dynamic trapping-releasing operations, by simply stretching and releasing the elastomer chip.

Functional Characteristics and Mechanical Performance of PCU Composites for Knee Meniscus Replacement

The potential use of fiber-reinforced based polycarbonate-urethanes (PCUs) as candidate meniscal substitutes was investigated in this study. Mechanical test pieces were designed and fabricated using a compression molding technique. Ultra-High Molecular Weight Polyethylene (UHMWPE) fibers were impregnated into PCU matrices, and their mechanical and microstructural properties evaluated. In particular, the tensile moduli of the PCUs were found unsuitable, since they were comparatively lower than that of the meniscus, and may not be able to replicate the inherent role of the meniscus effectively. However, the inclusion of fibers produced a substantial increment in the tensile modulus, to a value within a close range measured for meniscus tissues. Increments of up to 227% were calculated with a PCU fiber reinforcement composite. The embedded fibers in the PCU composites enhanced the fracture mechanisms by preventing the brittle failure and plastic deformation exhibited in fractured PCUs. The behavior of the composites in compression varied with respect to the PCU matrix materials. The mechanical characteristics demonstrated by the developed PCU composites suggest that fiber reinforcements have a considerable potential to duplicate the distinct and multifaceted biomechanical roles of the meniscus.