WMS based dual-range real-time trace sensor for ethane detection in exhaled breath

In August 2022 scientific group from the China University of Petroleum, Chinese Academy of Sciences and Sichuan Cancer Hospital & Institute published in Optics and Lasers Engineering (Elsevier) an article where they describe a system for early screening and diagnosis of lung cancer based on VIGO product.

The presented traced sensor uses ethane as an ideal exhaled biomarker. Authors wrote that ethane concentration in the exhaled breath of patients with lung cancer is higher than that of healthy people and the concentration of biomarkers exhaled during different periods of the disease varies greatly. They pointed out that detecting and screening ethane at high sensitivity with a single concentration range is a big challenge.

Scientists used an interband cascade laser (ICL) to target the ethane absorption band near 3.34 μm as a light source. They decided to use an HgCdTe immersed detector (MCT) at response range 2.5 μm -7 μm posted in LabM-I-6 module with a programable preamplifier made by VIGO Photonics. Using wavelength modulation spectroscopy (WMS) techniques of tunable diode laser absorption spectroscopy (TDLAS), allows them for highly sensitive detection in ethane concentration ranges. By performing the Allan deviation and indicating the limit of detection of the sensor system up to ~269 ppt over the entire integration time (2 h) the scientists proved that the used VIGO module is highly stable in long-term operation.

The authors pointed out that described trace sensor equipped with VIGO module provides high sensitivity, linearity and accuracy for the detection of ethane in exhaled breath at ppm-level and ppb-level. Such innovative medical applications reveal new possibilities for exploiting infrared detectors. 

Link to the article