title: Multi-dimensional super-resolution imaging enables surface hydrophobicity mapping.
abstract: Super-resolution microscopy allows biological systems to be studied at the nanoscale, but has been restricted to providing only positional information. Here, we show that it is possible to perform multi-dimensional super-resolution imaging to determine both the position and the environmental properties of single-molecule fluorescent emitters. The method presented here exploits the solvatochromic and fluorogenic properties of nile red to extract both the emission spectrum and the position of each dye molecule simultaneously enabling mapping of the hydrophobicity of biological structures. We validated this by studying synthetic lipid vesicles of known composition. We then applied both to super-resolve the hydrophobicity of amyloid aggregates implicated in neurodegenerative diseases, and the hydrophobic changes in mammalian cell membranes. Our technique is easily implemented by inserting a transmission diffraction grating into the optical path of a localization-based super-resolution microscope, enabling all the information to be extracted simultaneously from a single image plane.
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Marie N
authors.initials: MN
authors.lastname: Bongiovanni
authors.affiliation: Laboratoire de Biophotonique et Pharmacologie, UMR CNRS 7213, Université de Strasbourg, Faculté de Pharmacie, 67400 Illkirch, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Godet
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Mathew H
authors.initials: MH
authors.lastname: Horrocks
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.|DTI Laboratory of Neurodegenerative Diseases, Centre for Integrative Biology Università degli Studi di Trento, via Sommarive 9, Trento 38123, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Tosatto
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Carr
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: David C
authors.initials: DC
authors.lastname: Wirthensohn
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Rohan T
authors.initials: RT
authors.lastname: Ranasinghe
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Ji-Eun
authors.initials: JE
authors.lastname: Lee
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Aleks
authors.initials: A
authors.lastname: Ponjavic
authors.affiliation: Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, 7 avenue des Hauts-Fourneaux, Esch-sur-Alzette, Luxembourg L-4362, Luxembourg.
authors.forename: Joelle V
authors.initials: JV
authors.lastname: Fritz
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Dobson
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: David
authors.initials: D
authors.lastname: Klenerman
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors.forename: Steven F
authors.initials: SF
authors.lastname: Lee