Rapid tests for COVID-19 can help to avoid further transmission. Noninvasive, fast breath tests could be a useful tool in this context, especially for mass screenings. In such tests, breath volatile organic compounds (BVOCs) are used as biomarkers specific to COVID-19. However, the usual standard method for detecting BVOCs is gas chromatography coupled to mass spectrometry (GC–MS), which requires large, expensive equipment and is, thus, not suited to on-site testing.
Xing Yi Ling, Nanyang Technological University, Singapore, and colleagues have developed a surface-enhanced Raman scattering (SERS)-based breathalyzer-type device that can sensitively and accurately detect COVID-19 in less than five minutes. Test subjects breathe into the device for 10 s. BVOCs in the breath sample then interact with different surface receptors on the SERS sensor in the device. The team used Ag nanocubes, surface-functionalized with 4-mercaptobenzoate (MBA), 4-mercaptopyridine (MPY), or 4-aminothiophenol (ATP).
The interactions between the BVOCs and the sensor lead to spectral changes that can be detected using a portable Raman spectrometer. In tests with 501 participants, using PCR tests as a control, the device achieved a sensitivity of 96.2 % and a specificity of 99.9 % The accuracy was independent of whether the tested individual showed symptoms related to COVID-19. The short time from sample collection to result and the option to perform tests in parallel could make the method useful for testing many people in high-traffic locations, such as airports or large events.
- Noninvasive and Point-of-Care Surface-Enhanced Raman Scattering (SERS)-Based Breathalyzer for Mass Screening of Coronavirus Disease 2019 (COVID-19) under 5 min,
Shi Xuan Leong, Yong Xiang Leong, Emily Xi Tan, Howard Yi Fan Sim, Charlynn Sher Lin Koh, Yih Hong Lee, Carice Chong, Li Shiuan Ng, Jaslyn Ru Ting Chen, Desmond Wei Cheng Pang, Lam Bang Thanh Nguyen, Siew Kheng Boong, Xuemei Han, Ya-Chuan Kao, Yi Heng Chua, Gia Chuong Phan-Quang, In Yee Phang, Hiang Kwee Lee, Mohammad Yazid Abdad, Nguan Soon Tan, Xing Yi Ling,
ACS Nano 2022.
Also of Interest
- Collection: SARS-CoV-2 Virus
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