Microwave-assisted synthesis of fluorescent graphene quantum dots from ferula asafoetida: a green approach for efficient nanomaterial production and selective detection of serum Fe³⁺ ions

Abstract In the pursuit of economical methods for nanomaterial synthesis, microwave-assisted techniques have garnered attention for their simplicity, efficiency, and reduced time requirements. This study presents a novel approach for the synthesis of fluorescent graphene quantum dots (FGQDs) via a one-pot microwave-assisted method, utilizing Ferula Asafoetida as a green precursor. The resulting FGQDs, synthesized without the need for a catalyst, exhibit high concentration and stability. Notably, these FGQDs display robust blue luminescence across a range of pH and temperature conditions, with the highest quantum yield (18.92%) achieved, as determined by comparison with quinine sulfate standards. The x-ray diffraction analysis shows slightly crystallizable carbonized nanomaterial with particle size ranging from 4–7 nm. The transmission electron microscopy presents unique structural, morphological while x-ray photoelectron spectroscopy shows embedded oxygen containing functional groups responsible for high luminescence intensity. Characterization through various analytical techniques including Raman spectroscopy, dynamic light scattering, verifies the carbon backbone and stability of FGQDs. Detection and quantification limits of Fe 3+ ion were determined to be 0.05 mM and 0.01 nM respectively, with FGQDs enabling the estimation of low serum Fe 3+ levels, reaching 4 ppm. Furthermore, the synthesized FGQDs hold promise for applications in drug delivery and intracellular sensing due to their high fluorescent intensity and stability.