Multiplexed fibre optic sensing in the distal lung

Proteus (www.proteus.ac.uk) is a major EPSRC funded ‘Interdisciplinary Research Collaboration’ involving three partner Universities, some 18 post-doctoral researchers and 20 PhD students across 10 research groups. Pulmonary infection and inflammation account for a massive burden of disease and death in the world, yet despite this, very little is known about the processes that drive lung disease. A significant hurdle has been the lack of tools and approaches that are able to interrogate and sense the biology of the gas-exchanging (alveolar) regions of the human lung in situ.
Work at the Queen’s Medical Research Institute Hub on fibre optic spectroscopy systems brings together the technologies from across the project and applies them to biological models. Novel measurement techniques take advantage of bespoke multicore fibres fabricated at the University of Bath combined with customised chemical sensors from the department of Chemistry (U of E). Proteus single photon detector arrays from Engineering (U of E) exploit additional dimensions of the probe signals. This paper will summarise how these Proteus technologies have been combined to overcome technical challenges and offer enhanced spectroscopic measurements through fibre in biological systems with the aim of aiding the clinician with diagnosis in the distal lung, including:
•Surface Enhanced Raman Sensors (SERS) on the end of custom multicore optical fibres, and application to pH measurement in realistic lung models.
•Attachment of fluorescent microsphere probes to multicore optic fibre for multiplexed measurement of pH and oxygen levels in the lung.
•Time resolved single photon counting spectroscopic techniques for enhanced measurement of the above and aiding disambiguation between probe and tissue fluorescent signals.