title: Quantitative measurement of redox potential in hypoxic cells using SERS nanosensors.
abstract: Hypoxia is considered to be a reductive disorder of cells that is caused either by a lack of oxygen or by the dysregulation of metabolic pathways and is thought to play a role in the pathology of diseases including stroke and cancer. One aspect of hypoxia that remains poorly investigated is the dysregulation of cellular redox potential and its role in controlling biological pathway activation. Since there is currently no way of quantitatively measuring the intracellular redox potential of hypoxic cells, this provided us with the motivation to develop optical nanosensors whose Surface-Enhanced Raman (SER) spectrum provides a quantitative measure of redox potential in hypoxic cells. Our nanosensors are made from organic reporter molecules that show oxidation-state-dependent changes in the Raman spectrum and are chemically adsorbed onto gold nanoshells. These nanosensors can be taken up by cells, and by collecting the SER spectrum we can calculate the localised intracellular redox potential from single hypoxic cells in a non-invasive, reversible way.
authors.affiliation: EaStCHEM, School of Chemistry, Joseph Black Building, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK. colin.campbell@ed.ac.uk.
authors.forename: Jing
authors.initials: J
authors.lastname: Jiang
authors.forename: Craig
authors.initials: C
authors.lastname: Auchinvole
authors.forename: Kate
authors.initials: K
authors.lastname: Fisher
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Campbell
mesh_terms: D015374:Biosensing Techniques; D045744:Cell Line, Tumor; D004563:Electrochemistry; D004583:Electrons; D006046:Gold / Q000737:chemistry; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D000860:Hypoxia; D053768:Metal Nanoparticles / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D009243:NAD / Q000737:chemistry; D009249:NADP / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology; D009369:Neoplasms / Q000473:pathology; D055095:Optics and Photonics; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D013059:Spectrum Analysis, Raman
chemical_list: D009243:NAD; D049452:Green Fluorescent Proteins; D009249:NADP; D006046:Gold; D010100:Oxygen