Synthesis of Carbon Quantum Dots and Fe-Doped Carbon Quantum Dots as Fluorescent Probes via One-Step Microwave Process for Rapid and Accurate Detection of Diclofenac Sodium

In the current study, the carbon quantum dots (CDs) were synthesized through a facile, rapid, and one-step microwave method using citric acid monohydrate and urea. The as-prepared CDs were spherical with diameters of 3-4 nm and displayed bright blue fluorescent under an excitation wavelength of 360 nm. Also, the as-prepared CDs had various properties, including high quantum yield (& AP;18%), favorable solubility in water, different functional groups, significant stability in various environmental conditions, and excellent optical performance. The results indicated that the CDs could be applied as a fluorescent probe for reliable and accurate detection of Diclofenac sodium (DFS) based on the enhancement of their native fluorescent intensity (turn-on). The emission spectra of the as-prepared CDs were strengthened gradually when the DFS concentration increased from 5 to 300 & mu;M. In addition, the linear relationship was fabricated over the concentrations range of 5-300 & mu;M for DFS with the detection limit of 2.33 & mu;M. Furthermore, the findings showed that Fe doped CDs (Fe-CDs) like CDs have a good ability to detect various concentrations of DFS in the wide range of 5-300 & mu;M.