title: Endoscopic sensing of alveolar pH.
abstract: Previously unobtainable measurements of alveolar pH were obtained using an endoscope-deployable optrode. The pH sensing was achieved using functionalized gold nanoshell sensors and surface enhanced Raman spectroscopy (SERS). The optrode consisted of an asymmetric dual-core optical fiber designed for spatially separating the optical pump delivery and signal collection, in order to circumvent the unwanted Raman signal generated within the fiber. Using this approach, we demonstrate a ~100-fold increase in SERS signal-to-fiber background ratio, and demonstrate multiple site pH sensing with a measurement accuracy of ± 0.07 pH units in the respiratory acini of anex vivoovine lung model. We also demonstrate that alveolar pH changes in response to ventilation.
authors.affiliation: Scottish Universities Physics Alliance (SUPA), Institute of Photonics and Quantum Sciences (IPaQS), Heriot-Watt University, Edinburgh, UK; EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK; These authors contributed equally to this work.
authors.forename: D
authors.initials: D
authors.lastname: Choudhury
authors.affiliation: Scottish Universities Physics Alliance (SUPA), Institute of Photonics and Quantum Sciences (IPaQS), Heriot-Watt University, Edinburgh, UK; EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK; These authors contributed equally to this work.
authors.forename: M G
authors.initials: MG
authors.lastname: Tanner
authors.affiliation: EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK; School of Chemistry, University of Edinburgh, Edinburgh, UK.
authors.forename: S
authors.initials: S
authors.lastname: McAughtrie
authors.affiliation: Centre for Photonics and Photonic Materials, Department of Physics, University of Bath, Bath, UK.
authors.forename: F
authors.initials: F
authors.lastname: Yu
authors.affiliation: EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK.
authors.forename: B
authors.initials: B
authors.lastname: Mills
authors.affiliation: EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK; Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK.
authors.forename: T R
authors.initials: TR
authors.lastname: Choudhary
authors.affiliation: School of Informatics, University of Edinburgh, Edinburgh, UK.
authors.forename: S
authors.initials: S
authors.lastname: Seth
authors.affiliation: EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK; Pulmonary Molecular Imaging Group, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK.
authors.forename: T H
authors.initials: TH
authors.lastname: Craven
authors.affiliation: Centre for Photonics and Photonic Materials, Department of Physics, University of Bath, Bath, UK.
authors.forename: J M
authors.initials: JM
authors.lastname: Stone
authors.affiliation: School of Chemistry, University of Edinburgh, Edinburgh, UK.
authors.forename: I K
authors.initials: IK
authors.lastname: Mati
authors.affiliation: School of Chemistry, University of Edinburgh, Edinburgh, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Campbell
authors.affiliation: EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK; School of Chemistry, University of Edinburgh, Edinburgh, UK.
authors.forename: M
authors.initials: M
authors.lastname: Bradley
authors.affiliation: School of Informatics, University of Edinburgh, Edinburgh, UK.
authors.forename: C K I
authors.initials: CK
authors.lastname: Williams
authors.affiliation: EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK; Pulmonary Molecular Imaging Group, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK.
authors.forename: K
authors.initials: K
authors.lastname: Dhaliwal
authors.affiliation: Centre for Photonics and Photonic Materials, Department of Physics, University of Bath, Bath, UK.
authors.forename: T A
authors.initials: TA
authors.lastname: Birks
authors.affiliation: Scottish Universities Physics Alliance (SUPA), Institute of Photonics and Quantum Sciences (IPaQS), Heriot-Watt University, Edinburgh, UK; EPSRC IRC Hub, MRC Centre for Inflammation Research, Queen's Medical Research Institute (QMRI), University of Edinburgh, Edinburgh, UK.
authors.forename: R R
authors.initials: RR
authors.lastname: Thomson
keywords: (170.4580) Optical diagnostics for medicine; (170.6510) Spectroscopy, tissue diagnostics