Integrating a Fluorogenic Strategy With a SALLE Technique Through One‐Pot Derivatization of Nonfluorescent Heptaminol Drug: Quantification in Human Plasma and Urine With a Comprehensive Sustainability Profile and Quantum Yield Evaluation

ABSTRACT

A green, highly sensitive analytical platform integrating salting‐out assisted liquid–liquid extraction (SALLE) with one‐pot spectrofluorimetric derivatization has been developed for heptaminol, a cardiovascular agent, in human plasma and urine. In this method, heptaminol is first isolated from biological fluids via SALLE using acetonitrile/ammonium sulphate, yielding a clean extract. Next, a nucleophilic substitution reaction with 4‐chloro‐7‐nitrobenzo‐2,1,3‐oxadiazole in the borate buffer system produces a highly fluorescent nitrobenzo‐2,1,3‐oxadiazole derivative. Fluorescence is tracked at λ _ex   =  470 nm and λ _em   =  535 nm. All reaction parameters were optimized, affording a linear calibration range of 0.05–0.55 µg mL ⁻¹ , LOD of 0.016 µg mL ⁻¹ , and excellent accuracy (> 98% recovery) with no interference from common excipients. The planned method was fully validated per the International Council for Harmonization rules, ICH Q2 (R1), and applied to bulk drug, tablet content uniformity, and human plasma/urine analyses. A full sustainability profile, greenness, whiteness, bluness, and redness tools, plus quantum yield estimation, were performed, showing minimal organic solvent use and strong eco‐performance. This eco‐friendly SALLE–fluorimetric coupling protocol delivers rapid, reliable heptaminol quantification in pharmaceutical and clinical settings.