Usage of graphene quantum dots as a fluorescent sensor for highly efficient determination of Biotin in food samples

Biotin which also known as vitamin H, is synthesized by bacteria and plants but cannot be generated by humans, so it must be obtained by dietary sources [1]. Biotin deficiency could cause different health issues, especially complicated in children and pregnant women. Quantum dots (QDs) are colloidal semiconductor nanocrystals with excellent photoluminescent properties, high quantum yields and high resistance to photobleaching. Recently, QD-based photoluminescent nanosensing techniques have provided new advances in the field of molecules determination for environmental monitoring and food quality control [2]. Graphene quantum dots (GQDs) [3,4] was synthesized and used as a selective fluorescent probe for biotin detection. In this work, GQDs sensor was utilized as a fluorescence probe for the highly sensitive and selective determination of biotin infood samples. When biotin is added to the medium that has a GQDs sensor, fluorescence quenching of this analyte is happened which is related to the concentration of the biotin. The mechanism of the GQDs sensing system was investigated by recording UV-vis and fluorescence. The resulting composites were verified by X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR). The morphology of GQDs which was characterized by SEM. Under the optimal conditions, the relative fluorescence intensity linearly decreased with the concentration of biotin in the range of μg L−1.The method was applied to the determination of biotin in spiked food samples with satisfactory results.