High-Throughput Screening of FRET-Based Protein Rulers Using a Hyperspectral Microcapillary Array

FRET (Fluorescence Resonance Energy Transfer) is a versatile technique used in biology, chemistry, and materials science that involves distance-dependent energy transfer between light-sensitive molecules. Current FRET screening methods are limited when handling large libraries. Challenges include a low dynamic range, overlapping spectra, multiple fluorophores, and high background signals. A high-throughput FRET approach enables rapid, multiplexed screening of interactions, conformations, and dynamics with accurate, real-time measurements. We developed a hyperspectral high-throughput microcapillary array (HyCAP), which is ideal for sorting large clone libraries based on fluorescence assays. Our platform provides sensitive, high-resolution hyperspectral imaging with a throughput of approximately 10 ⁵ per array. FRET protocols can be used to study variations in protein structure and assemblies. HyCAP demonstrates potential in fluorophore engineering, including emission changes related to environment (such as pH, enzymatic activity, and temperature), stoichiometry differences, fluorophore orientation, and photobleaching through time-resolved experiments.