Determination of Diazepam Based on Flurescence Quenching of Quantum Dots of Cadmium Sulfide
Subject Areas : The Application of Chemistry in Environment
Keywords: Diazepam, quantum dots of cadmium sulfide, quenching fluorescence,
Abstract :
In this work we have developed a new method for determination of diazepam based on fluorescence quenching of quantum dots of cadmium sulfide. The quantum dots of CdS which have a good solubility and were stable in water, were exhibited a good fluorescence. Diazepam is one of the long acting benzodiazepines and has several p bonds in its chemical structure. Here, the effects of important parameters on the determination of diazepam were studied and optimized. Phosphate was identified as the most adequate buffer, and pH=7 as the optimum pH value and the addition of 50 μL of cadmium sulfide quantum dot solution was known as optimum condition. Calibration curve with a linear correlation coefficient of 0.9964 in the concentration range of 0.1-1.2 μg/L were obtained. Relative standard deviation for two different concentrations of diazepam were 1.17 (200 μg/L), and 1.64 (500 μg/L). Limit of detection were obtained to be 75 μg/L. This method presented as a simple, economic, sensitive, and relatively free from significant interferences from other species existing in the medium.
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