Flow-injection chemiluminescence analysis for sensitive determination of atenolol using cadmium sulfide quantum dots

A sensitive, rapid and simple flow-injection chemiluminescence (CL) system based on the light emitted from KMnO₄-cadmium sulfide quantum dots (CdS QDs) reaction in the presence of cetyltrimethylammonium bromide (CTAB) in acidic medium was developed as a CL probe for the sensitive determination of atenolol. Optical and structural features of CdS QDs capped with l-cysteine, which synthesized via hydrothermal approach, were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and UV-Vis spectroscopy. The CL intensity of KMnO₄-CdS QDs-CTAB was remarkably enhanced in the presence of trace level of atenolol. Under optimum experimental conditions, there is a linear relationship between the increase in CL intensity of KMnO₄-CdS QDs-CTAB system and atenolol concentration in a range of 0.001 to 4.0 mg L^{- 1} and 4.0 to 18.0 mg L^{- 1}, with a detection limit (3σ) of 0.0010 mg L^{- 1}. A possible mechanism for KMnO₄-CdS QDs-CTAB-atenolol CL reaction is proposed. To prove the practical application of the KMnO₄-CdS QDs-CTAB CL method, the method was applied for the determination of atenolol in spiked environmental water samples and commercial pharmaceutical formulation. Furthermore, corona discharge ionization ion mobility spectrometry (CD-IMS) technique was utilized for determination of atenolol.