Plate Reader Compatible 3D-Printed Device for Teaching Equilibrium Dialysis Binding Assays

Plasma protein binding measurements are an important aspect of pharmacology and drug development. Therefore, performing these measurements can provide a valuable and highly practical learning experience for students across many scientific disciplines. Here, we describe the design and characterization of a 3D-printed device capable of performing equilibrium dialysis in order to measure the binding affinity between a fluorescent ligand and a common plasma protein. The device is designed for laboratory automation, having dimensions identical to those of a standard 96-well plate, allowing it to be placed into a plate reader for direct fluorescence quantitation of free ligand. Traditional equilibrium dialysis experiments initially require 5–14 h of user attention; however, a “hands-free” approach is enabled by the technology in this paper, allowing the user to set up the device in a 1 h time period and return the next day for data analysis. Here, we include instructions for measuring and calculating the ligand...