TEOS-coated nanocomposite SERS substrate for breath biomarker detection

Abstract

Breath biopsy is a non-invasive method for detecting various biomarkers present in respiratory droplets. Conventional techniques like PCR and gas chromatography-mass spectrometry have drawbacks such as long measurement times and complexity. Surface-enhanced Raman spectroscopy (SERS) offers high sensitivity and selectivity, making it suitable for breath aerosol biomarker detection. However, the high velocity and small volume of breath aerosols often cause rebounding from SERS substrates, reducing collection efficiency. To address this, we developed TEOS-coated nanocomposite SERS substrates to enhance breath aerosol sample adsorption. The substrates were fabricated by thermally dewetting a thin Au film, and TEOS was coated using plasma-enhanced chemical vapor deposition (PECVD) technology. The porous nature of the TEOS coating physically entraps aerosols, leading to efficient capture. This innovative approach enables rapid collection and high aerosol concentration for SERS analysis of breath samples. By improving sample collection efficiency, our method enhances the potential of SERS for breath analysis in clinical applications.