Fig. 4

Preliminary binding test of the GST-His8-mCherry protein purified using MNP1. a Schematic diagram of protein separation using MNP1. A protein of interest such as GST-His₈-mCherry (red) was employed for protein-MNP capture, and the released mCherry protein could be visualized by UV detection during the whole process. The study was simply performed by allowing the protein to bind (I) and to be collected by a magnet (II), followed by washing and elution (III). The remaining bound protein on the MNPs was denatured by heating (95 °C, 10 min) in SDS-PAGE loading buffer (IV). b Bare MNP1, loading, flow-through, and elution samples were illuminated under UV light. (C) MNP1 allowed efficient single-step purification as proven by SDS-PAGE (left) and western blot analysis using Anti-Strep-tag II (right)