2.3 Vertical Transport Mixing Evaluation
Multi-well plates (96-well) were designed to evaluate vertical transport in cell culture plates. Plates were prepared using RBL-posts affixed to an acrylic substrate (RBL proprietary method). Biocompatible adhesive spacers were cut with CO2 laser to model 96-well XY dimensions. Using these spacers, the RBL posts were bonded to the underside of clear no-bottom 96-well microplates (Greiner Bio One 655000), creating an open-well chamber with RBL posts covering the floor of the wells. Each well was first filled with 200 µL clear 1% solution of Triton X-100 (Thermo Scientific™ 85111) and then the multi-well plate was placed over a 1-inch drive magnet (120 mT). Afterward, a 7.5µL volume of dilute blue food dye was delivered via pipet along the well periphery and allowed to settle. At this time, the drive system was engaged at the appropriate rpm (3000, 6000, 9000) and real-time videos were captured using LCD digital microscope. Quantitative analysis of the axial transport mixing videos was performed by determining the number of pixels the indicator dye traveled from the established baseline boundary. These values were calculated at each selected time interval (1 min.) and the distance traveled was reported in millimeters.