Pulse Dipolar Electron Paramagnetic Resonance Spectroscopy Distance Measurements at Low Nanomolar Concentrations: The Cu^II-Trityl Case.

ABSTRACT: Recent sensitivity enhancements in pulse dipolar electron paramagnetic resonance spectroscopy (PDS) have afforded distance measurements at submicromolar spin concentrations. This development opens the path for new science as more biomolecular systems can be investigated at their respective physiological concentrations. Here, we demonstrate that the combination of orthogonal spin-labeling using Cu^II ions and trityl yields a >3-fold increase in sensitivity compared to that of the established Cu^II-nitroxide labeling strategy. Application of the recently developed variable-time relaxation-induced dipolar modulation enhancement (RIDME) method yields a further ∼2.5-fold increase compared to the commonly used constant-time RIDME. This overall increase in sensitivity of almos

SUBMITTER: Ackermann K 

PROVIDER: S-EPMC10860127 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature