First clinical evaluation of a quartz enhanced photo-acoustic CO sensor for human breath analysis

• DOI: 10.1016/j.snb.2020.128247
• Publication Date: 2020-05-20T16:56:59Z
• Authors: Nicolas Maurin; Roman Rousseau; Wioletta Trzpil; Guillaume Aoust; Maurice Hayot; Jacques Mercier; Michael Bahriz; Fares Gouzi; Aurore Vicet
• Keywords: [SDV]Life Sciences [q-bio]; 02 engineering and technology; 0210 nano-technology

Abstract We present a carbon monoxide (CO) sensor dedicated to human breath analysis, based on quartz enhanced photo-acoustic spectroscopy (QEPAS). An off-beam configuration was chosen for the sensor, using a quantum cascade laser emitting at 4.7 μm. The detection was based on a second harmonic wavelength modulation scheme. A minimum detection limit of 20 parts per billions in volume (ppbv) in 1 s was obtained. First tests were performed on smokers/non smokers to validate the stability and the ability of the sensor to be used in vivo. Then a detailed validation of the sensor was performed in Montpellier Hospital by testing the CO-QEPAS performance versus reference methods: blood carboxy-hemoglobin (COHb %) and clinical status. Additionally, the performance was compared with commercial exhaled CO analyzer measurements. A full clinical evaluation of the sensor showed good reliability and agreement with the reference method (COHb %) of the CO-QEPAS in healthy subjects, confirming the ability of our CO sensor for measuring low level endogenous exhaled CO concentrations.