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Title: Advanced Photothermal Spectroscopy for Trace PFAS Detection
The widespread industrial and consumer use of per- and polyfluoroalkyl substances (PFAS) has led to their persistent presence in the environment, driven by their robust carbon-fluorine bonds and bioaccumulative properties. This contamination poses serious health and ecological risks, making real-time, selective, and sensitive detection of PFAS critical for effective mitigation. We demonstrate a selective and sensitive detection of vapor-phase PFAS using photothermal cantilever deflection spectroscopy (PCDS), achieving a detection limit of ∼30 pg. This method eliminates the need for chemically selective coatings, relying instead on the physisorption of PFAS molecules onto a bi-material microcantilever. By leveraging mid-infrared absorption and monitoring both cantilever bending and resonance frequency, PCDS enables simultaneous chemical identification and mass quantification. The technique demonstrates high selectivity in the mid-infrared fingerprint region and rapid desorption of analytes, offering significant advantages for real-time environmental monitoring and public health protection.  more » « less
Award ID(s):
2226614
PAR ID:
10565757
Author(s) / Creator(s):
; ;
Publisher / Repository:
The Electrochemical Society
Date Published:
Journal Name:
ECS Sensors Plus
Volume:
4
Issue:
1
ISSN:
2754-2726
Format(s):
Medium: X Size: Article No. 013401
Size(s):
Article No. 013401
Sponsoring Org:
National Science Foundation
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