Bakshi, S.Snoswell, A.J.Kwok, K.Y.Cheng, L.H.Altalhi, T.A.Santos, A.Popat, A.Kumeria, T.2022-02-042022-02-042022Advanced Functional Materials, 2022; 32(16)1616-301X1616-3028https://hdl.handle.net/2440/134263Published online: January 2, 2022A versatile “Spray-n-Sense” sprayable nanofiber technology for on-site chemical detection is demonstrated. Driven by compressed gas, the “Spray-n-Sense” nanofibers, as the name suggests, can be directly sprayed onto any kind or shape of surfaces, while the embedded chemical reporter enables simple colorimetric/fluorometric detection. Herein, nanofibers are sprayed on several surfaces including cardboard, glass, plastic, and rubber. The sensing capabilities of the “Spray-n-Sense” nanofibers are established through the detection of three different analytes including two metal ions (Fe²⁺ and Fe³⁺ using 1,10-phenanthroline and curcumin as chromogenic reporters, respectively) and ammonia (using rhodamine-B as a fluorogenic reporter) in aqueous media. Additional to being highly portable, the “Spray-n-Sense” nanofibers show impressive sensor characteristics with a sub-ppm lower limit of detection (LLOD) for Fe²⁺ and a wide linear working range. Whereas, the LLOD of 6.2 and 32 ppm is achieved for Fe³⁺ ions and ammonia, respectively. A custom-designed smartphone application enables quantitative analysis for reliable on-site sensing. The selectivity and specificity are imparted by the embedded reporter, and thus allow analyte detection in complex real-life samples and simultaneous detection of multiple chemical species through co-doping. The “Spray-n-Sense” nanofibers also allow for the detection of target analytes in solid samples.en© 2021 Wiley-VCH GmbHColorimetric sensing; metal ion sensing; nanofibers; nebulisation; on-site detectionJournal article10.1002/adfm.2021034962022-02-04598644Santos, A. [0000-0002-5081-5684]