Electron spin resonance is an analytical technique which detects paramagnetic free radicals, or spins and has been applied with remarkable impact to extremely diverse fields of research spanning biology, chemistry, and solid-state physics. Such paramagnetic species are broadly found in nature and can be intrinsic (defects in solid-state materials systems, electron/hole pairs, stable radicals in proteins) or, more often, purposefully introduced into the material of interest (doping/attachment of paramagnetic spin labels to biomolecules of interest). Despite the great analytical promise, the technique is greatly restricted by prohibitive insensitivity. The goal of this project is to circumvent this insensitivity and greatly expand the technique’s application space by using non-resonant detection.

Non-resonant detection greatly expands the possible fields of applicable research. Some demonstrated examples include (1) electrically detected magnetic resonance studies of the nature of specific solid-state point defects, (2) stopped-flow detection of various cell signaling pathways via spin labeling, and (3) atomic-force microscope-based spin resonance detection. The main intention in developing and employing all of these techniques at NIST is to provide a means to develop quantitative microscopic models of the physical, chemical, and biological processes that surround us.

 

Reference

Campbell JP, et al: “Electron Spin Resonance Scanning Probe Spectroscopy for Ultra-Sensitive Biochemical Studies.” Analytical Chemistry 87(9): 4910-4916, 2015

 

key words

Electron spin resonance; Electron paramagnetic resonance; Spin label; Electrically detected magnetic resonance; Atomic force microscopy; Defects; TEMPO; Membrane proteins; Cell signaling;

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral applicants