Hydroxyl radical-based protein footprinting (HRPF) coupled with mass spectrometry is a valuable medium-resolution technique in structural biology, facilitating the assessment of protein structure and molecular-level interactions in solution conditions. In HRPF with X-rays (XFP), hydroxyl radicals generated by water radiolysis covalently label multiple amino acid (AA) side chains. However, HRPF technologies face challenges in achieving their full potential due to the broad (>
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