The development of rapid and sensitive detection technology for identifying of chemicals and biological agents such as contraband substances, narcotics and toxins is critical for decision-making among first responders and military personnel. Recent advances in nanofabrication, microelectronics and computational power have led to miniaturization of portable analytical instruments. Among these, handheld Raman analyzer coupled with Surface Enhanced Raman spectroscopy (SERS), have become increasingly common for field detection challenges due to the enormous sensitivity of SERS technique. In this paper, we demonstrate the fabrication and analysis of flexible and porous paper-based SERS sensors by inkjet printing of colloidal Au nanoparticles (AuNP) onto paper substrate. Our paper-based SERS sensors are cost-effective and robust, and they provide the added advantage of point-of-sampling capability that rigid SERS sensors lack. With their inherent filtration sampling capability, we coupled our paper-SERS sensors with air pump for active sampling and detection of chemical aerosols. Additionally, we printed the SERS sensors in test strip format to enable swab sampling of chemical contaminants on door handle as a simulated field-sampling and detection of chemical toxins. Our swab sampling successfully picked up enough benzenethiol, BPE and fentanyl molecules to trigger positive detection. The used swab can also be preserved for further confirmatory tests such as paper-spray mass spectrometry.
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