In situ immunosorbant assay for 3D cell culture
* Experiments in progress
Many surfaces, both natural and synthetic, can be described as randomly rough, but rarely with a root-mean-square gradient as steep as g = 1. The selection of such a challenging surface parameter was intentional, but potentially limiting for broad comparisons across existing models and theories which may be limited by short angle approximations. By varying the root-mean-square gradients of the “Contact Mechanics Challenge” surface, and pressing each surface into contact with a PDMS elastic half space, contact measurements can be made in many conditions. In situ measurements of the real area of contact and contact-area distributions are performed using Frustrated Total Internal Reflectance (FTIR) along with surface deformation measurements performed using Digital Image Correlation (DIC). All of the loading is performed using a uniaxial load frame under force control. A Green’s Function Molecular Dynamics (GFMD) simulation for g = 1 is compared to all experimental data. The contact between PDMS and the 3D printed rough surface is measured in various loading rates, and surface conditions to obtain a complete understanding of how an elastic material responds to loading.