Sustainable Chemistry for the Environment (Sep 2023)
Detection of PFAS via surface-enhanced Raman scattering: Challenges and future perspectives
Abstract
The upsurge in the alarm about the hazardous effects of one of the important emerging contaminants, Per- and polyfluoroalkyl substances (PFAS) are increasing in recent days. Due to the widespread use of PFAS in various fields, it has a high tendency to be accumulated in the environment and living entities. Due to the persistent and carcinogenic nature of PFAS, it is necessary to detect and remove them from the environment. Chromatographic techniques combined with mass spectrometry are the current conventional methods for PFAS detection. Some more methods like liquid chromatography, solid-phase extraction, solid-phase mass extraction, tandem mass spectrometry, optical, electrochemical, fluorescence-based sensors, biosensors, etc. are also implemented to detect PFAS. Even though these methods could detect perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), the detection limits attained through these methods are unsatisfactory, and the detection of other PFAS has not been prioritized. Surface-enhanced Raman scattering (SERS) technique can be a great solution for the sensing of PFAS as it is highly sensitive, specific, and has a lot of potential in water research for the detection of contaminants. Due to the challenges associated with detecting PFAS using SERS, there is a limited amount of literature available on this topic. The reason behind this is the strong fluorescence nature of PFAS, and it is widely recognized that distinguishing fluorescence emission from Raman scattering is challenging due to their similar origins. In this perspective, causes for fluorescence in Raman scattering and the different ways to diminish the fluorescence are detailed in the later section. The article discusses the limitations of current PFAS sensors, advantages and limitations of fluorescence-based detection of PFAS in Raman scattering. The challenges related to the PFAS detection and possible solutions to resolve the issues have been focused. Further, an insightful discussion towards future research directions in this field has been provided.
