Fluorescence Sensing of Cu 2+ Ion and Some Organic Pollutants by Using Katiragum Dialdehyde‐α‐Amino Acid Schiff Bases in Aqueous Medium

Abstract Efficient and selective fluorescence sensors based on katiragum dialdehyde‐ amino acid Schiff's base is developed for fluorometric sensing to detect vanillin, Cu 2+ ions and 4‐nitrophenol (4NP) in their aqueous solution. Two Schiff bases namely katiragum dialdehyde‐ arginine (KGDR) and katiragum dialdehyde‐ tryptophan (KGDT) are developed in the author's laboratory between which KGDR can detect vanillin with a detection limit of 60.29 nM whereas KGDT can detect both Cu 2+ ion and 4NP with a detection limit of 72.6 nM and 97.83 nM respectively. KGDR and KGDT show significant quantum yields of 0.47 % and 0.25 % compared to a standard known substance fluorescein (0.97 %). The detection limit of vanillin, Cu 2+ ions and 4NP are lower than other reported sensors. The developed Schiff base KGDR and KGDT show excellent recovery percentage and relative standard deviation (RSD) values in real sample analysis.