Dataset Information

High fidelity fibre-based physiological sensing deep in tissue.

ABSTRACT: Physiological sensing deep in tissue remains a clinical challenge. Here a flexible miniaturised sensing optrode providing a platform to perform minimally invasive in vivo in situ measurements is reported. Silica microspheres covalently coupled with a high density of ratiometrically configured fluorophores were deposited into etched pits on the distal end of a 150?µm diameter multicore optical fibre. With this platform, photonic measurements of pH and oxygen concentration with high precision in the distal alveolar space of the lung are reported. We demonstrated the phenomenon that high-density deposition of carboxyfluorescein covalently coupled to silica microspheres shows an inverse shift in fluorescence in response to varying pH. This platform delivered fast and accurate measurements (±0.02?pH units and ±0.6?mg/L of oxygen), near instantaneous response time and a flexible architecture for addition of multiple sensors.

SUBMITTER: Choudhary TR

PROVIDER: S-EPMC6531436 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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High fidelity fibre-based physiological sensing deep in tissue.

Choudhary Tushar R TR Tanner Michael G MG Megia-Fernandez Alicia A Harrington Kerrianne K Wood Harry A HA Marshall Adam A Zhu Patricia P Chankeshwara Sunay V SV Choudhury Debaditya D Monro Graham G Ucuncu Muhammed M Yu Fei F Duncan Rory R RR Thomson Robert R RR Dhaliwal Kevin K Bradley Mark M

Scientific reports 20190522 1

Physiological sensing deep in tissue remains a clinical challenge. Here a flexible miniaturised sensing optrode providing a platform to perform minimally invasive in vivo in situ measurements is reported. Silica microspheres covalently coupled with a high density of ratiometrically configured fluorophores were deposited into etched pits on the distal end of a 150 µm diameter multicore optical fibre. With this platform, photonic measurements of pH and oxygen concentration with high precision in t ...[more]

PMID: 31118459

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Dataset Information

High fidelity fibre-based physiological sensing deep in tissue.

Publications

High fidelity fibre-based physiological sensing deep in tissue.

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