title: Detection of atomic spin labels in a lipid bilayer using a single-spin nanodiamond probe.
abstract: Magnetic field fluctuations arising from fundamental spins are ubiquitous in nanoscale biology, and are a rich source of information about the processes that generate them. However, the ability to detect the few spins involved without averaging over large ensembles has remained elusive. Here, we demonstrate the detection of gadolinium spin labels in an artificial cell membrane under ambient conditions using a single-spin nanodiamond sensor. Changes in the spin relaxation time of the sensor located in the lipid bilayer were optically detected and found to be sensitive to near-individual (4 ± 2) proximal gadolinium atomic labels. The detection of such small numbers of spins in a model biological setting, with projected detection times of 1 s [corresponding to a sensitivity of ∼5 Gd spins per Hz(1/2)], opens a pathway for in situ nanoscale detection of dynamical processes in biology.
authors.affiliation: Centre for Quantum Computation and Communication Technology, School of Physics, University of Melbourne, Parkville, VIC 3010, Australia.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kaufmann
authors.forename: David A
authors.initials: DA
authors.lastname: Simpson
authors.forename: Liam T
authors.initials: LT
authors.lastname: Hall
authors.forename: Viktor
authors.initials: V
authors.lastname: Perunicic
authors.forename: Philipp
authors.initials: P
authors.lastname: Senn
authors.forename: Steffen
authors.initials: S
authors.lastname: Steinert
authors.forename: Liam P
authors.initials: LP
authors.lastname: McGuinness
authors.forename: Brett C
authors.initials: BC
authors.lastname: Johnson
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ohshima
authors.forename: Frank
authors.initials: F
authors.lastname: Caruso
authors.forename: Jörg
authors.initials: J
authors.lastname: Wrachtrup
authors.forename: Robert E
authors.initials: RE
authors.lastname: Scholten
authors.forename: Paul
authors.initials: P
authors.lastname: Mulvaney
authors.forename: Lloyd
authors.initials: L
authors.lastname: Hollenberg
mesh_terms: D055592:Biophysical Phenomena; D004578:Electron Spin Resonance Spectroscopy; D005682:Gadolinium; D008051:Lipid Bilayers / Q000737:chemistry*; D060306:Magnetometry; D058612:Nanodiamonds; D036103:Nanotechnology; D013113:Spin Labels
chemical_list: D008051:Lipid Bilayers; D058612:Nanodiamonds; D013113:Spin Labels; D005682:Gadolinium
keywords: biophysics; nanomagnetometry; nitrogen-vacancy center