Hydrophobic silver nanowire membrane for swabbing extraction and in situ SERS detection of polycyclic aromatic hydrocarbons on toys

The migration of solid samples from the interior to the surface of materials has raised serious concerns due to the increasing environmental health hazards in recent years. The convenient in situ detection of polycyclic aromatic hydrocarbons (PAHs) is especially needed. Surface-enhanced Raman spectroscopy (SERS) has emerged as an effective tool for spectroscopic detection and gives unique spectroscopic fingerprints of analytes. In this study, a hydrophobic 1-propanethiol-modified Ag nanowire membrane (PTH-Ag NMs) coupled with a portable Raman spectrometer was developed for the flexible on-site swabbing extraction and detection of typical PAHs. The swabbing process using an extracting agent was similar to the contact between a baby's mouth and toys. The SERS substrate suggested high uniformity, stability, and reusability. The curve of the normalized SERS intensity against the fluoranthene concentration displayed a good linear relationship (R2 = 0.98). The detection levels of fluoranthene, anthracene and pyrene reached 40.45, 35.65, and 45.45 ng cm−2, respectively. In addition, the simulated detection of these three PAHs on children's toys was demonstrated. The prepared hydrophobic PTH-Ag NMs have potential applications in the field of the inspection of toys by a simultaneous processing with simple pretreatment and a short total analysis time.