Carbon-based nanomaterials are contemporary and are outpacing the technology platform. Graphene quantum dots (GQDs) had a significant impact on the subject of bioengineering, pharmaceuticals, biomedicine, biosensors, fuel, energy, etc. Depending on how quickly this field is developing, it is important to recognize the new difficulties that GQDs have to overcome. This is incredibly significant because many novel applications and innovations that have made GQD synthesis easier recently have not been systematically evaluated in prior studies. Their ability to combine the benefits of quantum dots, sp² carbon materials (large specific surface area), and have rich functional groups at the edge makes them special. The naturally occurring inert carbon helps to stabilize chemical and physical characteristics and makes significant advancements in the creation of benchmark photocatalysts. Moreover, current challenges and potential of these rapidly developing GQDs are emphasized. The future of GQD research is limitless, according to the assessment in this review, notably if future research focuses on simplicity of purification and ecofriendly synthesis. This feature article offers a realistic summary on recent developments in the synthesis, characteristics, and uses of GQDs. Frequent review articles focusing on the progress of GQDs for specific applications are published but a thorough review article on GQDs for their numerous uses has not yet been published. The recent trends of scientific research based on new optical biosensing applications, including the comprehensive applications of different zero-dimensional nanomaterials, specially GQDs are discussed in this study.

Antibiotic resistance is becoming more common, emphasising the demand for novel antibacterial treatments. The current investigation describes the green synthesis of graphene quantum dots (GQDs) using M. indica leaves and characterization via Fourier-transform infrared spectra (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and ultraviolet-visible (UV-Vis) spectrophotometer. The results showed that GQDs are spherical in shape. In vitro antioxidant and antimicrobial studies indicate that the biological efficacy of synthesized GQDs was higher than the ethanolic leaf extract. GQDs exhibited the highest scavenging efficacy with lowest IC₅₀ (half-maximal inhibitory concentration) value. However, antimicrobial study showed more inhibitory activity of GQDs against all screened microorganisms, i.e., Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa, and fungi, i.e., Aspergillus niger and Aspergillus flavus. Graphene quantum dots facilitate reactive oxygen species (ROS) which ultimately lead to antioxidant and antibacterial activity. This approach would provide an efficient alternate method for tackling microorganisms.