Fluorescence Analysis of Propranolol Hydrochloride Using Mercaptoacetic Acid-Capped Cadmium Sulfide Quantum Dots and...

Propranolol hydrochloride (PRO-HCl), a nonselective β-adrenergic receptor blocker, is widely utilized in the treatment of various medical conditions including hypertension, angina pectoris, cardiac arrhythmias, migraine prophylaxis, and certain anxiety disorders. In this study, we developed a simple, convenient, and sensitive quantitative detection method for PRO-HCl in aqueous environments, based on the fluorescence generated from the reaction between Cadmium sulfide quantum dots (CdS QDs) and PRO-HCl at room temperature. The synthesized CdS QDs were thoroughly characterized using fluorescence spectroscopy, UV-Vis spectrophotometry, and Fourier-transform infrared spectroscopy (FTIR) to investigate their optical and structural properties. Our experimental results demonstrated a significant enhancement in the fluorescence intensity of CdS QDs in the presence of low concentrations of propranolol hydrochloride. Through systematic optimization of experimental conditions, we established a linear relationship between the fluorescence intensity of CdS QDs and PRO-HCl concentration within the range of 0.002-8 mg·L^-1. The linear regression equation was determined to be Y = 0.6479X + 0.0685 with a correlation coefficient (R²) of 0.9858, and the detection limit was found to be 0.002 mg·L^-1. Furthermore, we investigated the potential reaction mechanism between CdS QDs and PRO-HCl. To validate the practical application of CdS QDs, the proposed method was successfully employed for the determination of PRO-HCl in spiked environmental water samples, demonstrating the effectiveness and reliability of the CdS QDs-based detection system.