Unfolding of Eco‐Innovative Multifunctional Switch‐Off Fluorescent Sensor for Omeprazole Sensing in Formulations and Environmental Samples

Abstract

ABSTRACT Investigations were applied for constructing carbon quantum dots (CDs) from a new natural source by environmentally benign techniques. Red grapes, rich in bioactive compounds, were utilized for the synthesis of S,N‐based CDs. Microwave‐assisted synthesis of CDs was applied with minimal radiation for just 6 min, which aligns with sustainability. Unlike traditional techniques that require harsh nongreen conditions, e.g., high temperature or charged molecules, this approach requires the standard household microwave temperature, which offers a readily available synthesis process with an excellent greenness level. The fabricated CDs exhibit powerful fluorescence ( λ ex / λ em of 350/445 nm) with superb water solubility. Stability and selectivity of CDs were confirmed in the presence of different ions. Crucially, the CDs were exploited for quantification of the anti‐GERD drug omeprazole (OPZ) for the first time by fluorescence quenching via static quenching. The method demonstrated an excellent regression coefficient (0.9999) and a detection limit of 0.335 μg/mL. This enabled successful OPZ estimation in dosage forms, river, and tap water with %recoveries of 99.72%–101.02%. Consequently, this sensor would be a promising avenue for quality control and environmental monitoring of micropollutants. The exceptional greenness degree was confirmed using different greenness evaluation systems: Complex‐GAPI, BAGI, AGREE, and nanomaterials assessment tool.