title: Microstructured Optical Fiber-based Biosensors: Reversible and Nanoliter-Scale Measurement of Zinc Ions.
abstract: Sensing platforms that allow rapid and efficient detection of metal ions would have applications in disease diagnosis and study, as well as environmental sensing. Here, we report the first microstructured optical fiber-based biosensor for the reversible and nanoliter-scale measurement of metal ions. Specifically, a photoswitchable spiropyran Zn(2+) sensor is incorporated within the microenvironment of a liposome attached to microstructured optical fibers (exposed-core and suspended-core microstructured optical fibers). Both fiber-based platforms retains high selectivity of ion binding associated with a small molecule sensor, while also allowing nanoliter volume sampling and on/off switching. We have demonstrated that multiple measurements can be made on a single sample without the need to change the sensor. The ability of the new sensing platform to sense Zn(2+) in pleural lavage and nasopharynx of mice was compared to that of established ion sensing methodologies such as inductively coupled plasma mass spectrometry (ICP-MS) and a commercially available fluorophore (Fluozin-3), where the optical-fiber-based sensor provides a significant advantage in that it allows the use of nanoliter (nL) sampling when compared to ICP-MS (mL) and FluoZin-3 (μL). This work paves the way to a generic approach for developing surface-based ion sensors using a range of sensor molecules, which can be attached to a surface without the need for its chemical modification and presents an opportunity for the development of new and highly specific ion sensors for real time sensing applications.
authors.affiliation: ARC Center of Excellence for Nanoscale BioPhotonics, Institute for Photonics and Advanced Sensing, Department of Chemistry, School of Physical Sciences, The University of Adelaide , Adelaide, South Australia 5005, Australia.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Heng
authors.affiliation: Research Center for Infectious Diseases, School of Biological Sciences, The University of Adelaide , Adelaide, South Australia 5005, Australia.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: McDevitt
authors.affiliation: ARC Center of Excellence for Nanoscale BioPhotonics, Institute for Photonics and Advanced Sensing, Department of Chemistry, School of Physical Sciences, The University of Adelaide , Adelaide, South Australia 5005, Australia.
authors.forename: Roman
authors.initials: R
authors.lastname: Kostecki
authors.affiliation: Research Center for Infectious Diseases, School of Biological Sciences, The University of Adelaide , Adelaide, South Australia 5005, Australia.
authors.forename: Jacqueline R
authors.initials: JR
authors.lastname: Morey
authors.affiliation: Research Center for Infectious Diseases, School of Biological Sciences, The University of Adelaide , Adelaide, South Australia 5005, Australia.
authors.forename: Bart A
authors.initials: BA
authors.lastname: Eijkelkamp
authors.affiliation: ARC Center of Excellence for Nanoscale BioPhotonics, Institute for Photonics and Advanced Sensing, Department of Chemistry, School of Physical Sciences, The University of Adelaide , Adelaide, South Australia 5005, Australia.
authors.forename: Heike
authors.initials: H
authors.lastname: Ebendorff-Heidepriem
authors.affiliation: The University of South Australia , Adelaide, South Australia 5000, Australia.
authors.forename: Tanya M
authors.initials: TM
authors.lastname: Monro
authors.affiliation: ARC Center of Excellence for Nanoscale BioPhotonics, Institute for Photonics and Advanced Sensing, Department of Chemistry, School of Physical Sciences, The University of Adelaide , Adelaide, South Australia 5005, Australia.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Abell
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D007477:Ions / Q000032:analysis*; D051379:Mice; D055100:Optical Fibers; D015032:Zinc / Q000032:analysis*
chemical_list: D007477:Ions; D015032:Zinc
keywords: biosensor; liposome; microstructured optical fiber; nanoscale; photoswitch; zinc