Nanofiber-Based Analytical Device (nFAD) as a Robust Alternative to Paper-Derived Platforms for Fluoride Sensing

We report the development of a nanofiber-based analytical device (nFAD) as a next-
generation platform for fluoride detection, offering a viable alternative to paper-based sensors.
The device comprises a porous network of plasticized, lipophilic polymer incorporating a
fluoride-selective corrole ionophore and an ion-exchanger. This nanofibrous sensing layer
enables camera-assisted optical readout of fluoride activity through colorimetric modulation
induced by the Si–corrole ionophore. The system exhibits a linear response between the
logarithm of fluoride concentration (10⁻⁶–10⁻¹ M) and the intensity of the red or green
color channels. Importantly, signal acquisition is rapid and does not require pH adjustment of
the sample matrix.[1]
The hydrophobic character of the polymeric environment confers stability while the nanofiber
architecture ensures mechanical resilience, flexibility, and chemical robustness. These
attributes collectively establish nFAD as a durable, optically transduced sensor suitable for
applications in environmental monitoring, medical diagnostics, and food safety. The platform
demonstrates the synergistic benefits of nanostructured materials and the high selectivity of
synthetic ionophores, underscoring its potential as a versatile analytical tool.[2]

[1] J. Kalisz, A. Jelińska, F. Caroleo, E. Jaworska, E. Stelmach, C. Di Natale, K. Maksymiuk,
R. Paolesse, A. Michalska, Sensors and Actuators B: Chemical, 441, 137945 (2025).
[2] A. Jelińska, J. Kalisz, D. Pociecha, K. Maksymiuk, A. Michalska, Electroanalysis, 36,
e202300287 (2023).