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arXiv · 2512.04787

2bNIRS: a portable, multi-distance, broadband oximeter and cytochrome-c-oxidase monitoring system for in vivo applications

Luca Giannoni·Archie Barraclough·Chiara Carnati·Frederic Lange·Ilias Tachtsidis
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Abstract

Conventional near-infrared spectroscopy (NIRS) instruments typically employ 2-3 wavelengths for monitoring tissue haemodynamics. However, the use of broadband illumination (hundreds of wavelengths) unlocks also the targeting of tissue metabolism by exploiting the wide differential-redox peak of absorption of cytochrome-c-oxidase (CCO). For this purpose, we present here a novel, broadband (780-900nm), multi-distance NIRS system, called 2bNIRS. Compact and portable (20 x 30 x 40 cm3), 2bNIRS was validated using a dynamic, optical phantom con-taining blood and yeast, and benchmarked against a multi-wavelength time-domain NIRS (TD-NIRS) system. Validation confirmed its accuracy in tracking haemody-namic and metabolic changes, with superior oximetry performance achieved via our BRUNO algorithm, which integrates broadband spectral fitting with spatially-re-solved analysis. Preliminary in vivo, human applications demonstrated 2bNIRS ap-plicability to monitoring both muscle tissue, during arm cuff occlusions, and the brain, during frontal cortex activation.

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Luca Giannoni, Archie Barraclough, Chiara Carnati, Frederic Lange, Ilias Tachtsidis. 2025-12-04. 2bNIRS: a portable, multi-distance, broadband oximeter and cytochrome-c-oxidase monitoring system for in vivo applications. https://arxiv.org/abs/2512.04787

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