Abstracts

In recent years, the presence of pharmaceutical residues, such as β-blockers, in the environment raised significant concerns on their potential risks to the ecosystem and human health. Therefore, sensitive and selective analytical methods are needed to determine β-blockers in environmental samples. The fluorescence spectrometric method is often applied to the determination of beta-blockers which generally exhibit natural fluorescence. However, the selectivity of fluorescence is often poor and can yield problems for the simultaneous determination of multi-component samples with broad bands and overlapped emission spectra. Therefore, synchronous fluorescence can be used for mixture analysis by removing the overlapping of individual fluorescence spectra. A synchronous fluorescence method is described for the simultaneous determination of atenolol (AT) and pindolol (PIN) in mixtures. This method can resolve the overlapping conventional fluorescence spectra of both compounds. The simultaneous fluorescence detection of AT and PIN is based on a single scan at 288 nm and 317 nm, corresponding to AT and PIN, at Δλ = 60 nm, respectively. Different experimental conditions that affect synchronous fluorescence, including Δλ and diluent solvent are optimized. The result shows that the ranges of linear calibration curves for both drugs are comprised between 25 and 1000 ng/ml in methanol. The limit of detection (LOD) for AT and PIN are 1.5 ng/ml and 1.8 ng/ml, respectively. The proposed method is successfully applied to the simultaneous determination of AT and PIN in spiked samples in tap and natural waters, by using the liquid-liquid extraction (LLE) procedure and standard addition with good recovery values ​​of 102 to 105% for AT and 96 to 102% for PIN.