Analyzing volatile organic compounds in breath by solid phase microextraction gas chromatography – mass spectrometry to diagnose COVID-19

SARS-CoV-2 was considered the third leading cause of death in the United States in 2020. Viral testing is the golden standard method to detect the virus. The downfall of current methods is the time that it takes to process and receive the sample results. Researchers have enhanced the diagnostic time from 3-5 days to hours. However, there is a need to create a point-of-care method to accelerate the detection of SARS-CoV-2. Volatile organic compound (VOC) metabolites are non-invasively expressed in breath and can differentiate a range of diseases. VOCs may be a rich source of biomarkers for diagnosis because COVID-19 drastically affects cellular metabolism for viral replication. Identifying these biomarkers facilitates the development of a point-of-care breathalyzer for SARS-CoV-2. Alveolar breath samples from COVID-19 positive (n=14) with symptoms and COVID-19 negative (n=12) were collected using Tedlar bags. The samples were cryotransferred to headspace vials and analyzed using gas chromatography-mass spectrometry quadrupole time-of-flight (GC-MS QTOF). Univariate and multivariate statistical analyses were applied to reduce complexity of the data and identify endogenous VOCs that related to COVID-19. The results indicate that a panel of three biomarkers can distinguish COVID-19 with 95% cross-validated accuracy. The discovery of these biomarkers led to future steps of the project, which is the development of a point-of-care COVID-19 breathalyzer.