DUAL-SIGNAL READOUT ANALYTICAL TOOLS: DESIGN, CHARACTERIZATION, AND APPLICATIONS IN SENSING

This thesis contributes to the field of chemical sensors by developing dual-signal detection devices that enhance both sensitivity and reliability. It introduces a new generation of bimodal and ratiometric sensors suitable for varied applications, especially in the crucial areas of health and environmental monitoring. The first project details a bimodal sensor designed for the simultaneous detection of cholesterol and o-toluidine, leveraging the combined strengths of electrochemistry and fluorescence. This integration is facilitated through the careful selection of fluoro-electroactive nanomaterials and cyclodextrins, enhancing selectivity. The second project explores a dual-detection sensor for nitrate ions, employing copper-modified graphitic carbon nitride to merge electrochemical and photoelectrochemical detection methods effectively. The third project outlines the development of a ratiometric sensor for diclofenac, incorporating a benzoquinone-modified mesoporous silica film, aimed at achieving unparalleled accuracy. The innovative integration of dual transduction modes within a single platform, alongside extensive optimization of nanomaterials and experimental approaches, addresses significant challenges in sensor development. The practical deployment of these sensors in real-world conditions has proven their operational effectiveness and potential to transform chemical detection technology.