A multi-chamber membrane separation electrophoresis system supporting bio-affinity screening and evaluation of...

An integrated platform of screening multi-compounds and evaluating bio-affinity is critical to explain the molecular mechanism of complex herbal medicine on various diseases. Here we developed a micro- and multi-chamber membrane separation electrophoresis system (MCMSE) based on the concept of bio-affinity, chamber-electrophoresis and membrane separation. It can enable simultaneous, rapid and high-throughput screening of multi- potential bioactive components in <15 min at low voltage (<35 V), which maintains the dynamic and original structure of biomacromolecules without immobilization. Based on the bio-affinity interaction and efficient separation of target protein/active components complexes and free small molecules, MCMSE demonstrates the function to determinate binding constants (K_b) between proteins and active components by the known interaction systems, with the potential for broad-spectrum determination. MCMSE has been applied to find 7 potential bioactive compounds of α-glucosidase (α-Gluc) from Scutellaria baicalensis Georgi extract, showing satisfactory screening reproducibility. Among these, the moderate bio-affinity interactions of three compounds with α-Gluc (isoschaftoside, baicalin, oroxylin A-7-O-glucuronide, wogonoside) were further verified by fluorescence quenching depending on the concentration of small molecules, with the K_b(s) =10⁴ ∼ 10⁵ M^-1. The proposed bio-affinity screening and evaluation system has the advantages of non-immobilization targets, fast, universality to be a potential way to explore the interaction between single-target and multi bioactive components and elucidate synergistic mechanism of herbal medicine.