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 fuorescent under an excitation wavelength of 360 nm. Also, the as-prepared CDs had various properties, including high quantum yield (≈18%), favorable solubility in water, diferent functional groups, signifcant stability in various environmental conditions, and excellent optical performance. The results indicated that the CDs could be applied as a fuorescent probe for reliable and accurate detection of Diclofenac sodium (DFS) based on the enhancement of their native fuorescent intensity (turn-on). The emission spectra of the as-prepared CDs were strengthened gradually when the DFS concentration increased from 5 to 300 µM. In addition, the linear relationship was fabricated over the concentrations range of 5–300 µM for DFS with the detection limit of 2.33 µM. Furthermore, the fndings 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 µM.
