Multipurpose biological applications of excitation-dependent fluorescent carbon nano dots emanated from biomass waste

Carbon Nanodots (CNDs) generated from biomass wastes have a wide range of biological functionalities and are used in a variety of applications. Especially, the biomedical applications shown by the CNDs derived from biomass waste materials received great attention from researchers around the globe. Herein we report the synthesis of CNDs from rice husk biomass waste using a hydrothermal method. XRD pattern demonstrates the amorphous nature of CNDs with hexagonal graphite structure. Microscopic images confirmed that as-synthesized CNDs are in spherical morphology with an average size of 25–30 nm and average interplanar spacing of 0.265 nm. XPS, Raman, and FTIR spectral analyses were performed to examine the presence of functional groups and defects in CNDs. Excitation-dependent emission properties of CNDs (Ф_F 9.6%) were studied by UV–Vis., Contour, and fluorescence techniques. In response to the findings of the cytotoxicity experiment and the CNDs' strong emission, we carried out several biostudies to prove its importance. The CNDs possess outstanding cell viability (98%), excellent anti-inflammatory activity of 33% of LOX, 34% of COX, 45% of NO inhibition at 100 μL, significant protein denaturation (62%; IC₅₀ 20.04 μL/mL), and bright bioimaging on Zebrafish characteristics, which accentuate the perception of waste to wealth.