Synthesis and cytocompatibility analysis of carbon nanodots derived from palmyra palm leaf for multicolor imaging applications

Abstract A humble and environmental benign preparation of carbon nanodots (CDs) utilizing palmyra leaves as a sustainable precursor, by hydrothermal method, is reported. The morphology, structure, optical and thermal behavior of CDs was investigated using transmission electron microscopy, photoluminescence spectroscopy UV–Vis spectroscopy, X-ray diffractometer, Fourier transform infrared spectroscopy and thermogravimetric analysis. The fluorescent CDs have a spherical shape and size of around 5–10 nm. The TEM images suggest that crystallinity of the carbon nanodots with a lattice parameter of 0.238 nm, corresponding to the (100) diffraction facets of graphite. The synthesized CDs biocompatibility was assessed using the cell viability assay and acridine orange/ethidium bromide (AO/EB) dual staining in human mesenchymal stem cells (hMSCs). The cell viability assay results exhibit that CDs slightly decrease the human mesenchymal stem cells viability at high dose. However, no remarkable changes were observed in cell viability. Furthermore, we assessed the CDs influence on nuclear morphology of hMSCs. These results clearly suggest that CDs treated cells have healthy and intact nuclei. Overall, our study results revealed that CDs have excellent compatibility on cells. Thus, the synthesized CDs can be used as versatile fluorescent probe for cellular imaging because of their excitation-dependent emission. Furthermore, we utilize the CDs as fluorescent probe for cellular imaging using confocal microscope, resulting tunable fluorescent emission. The CDs can enter the cells and accumulate in cytoplasmic region, symptomatic of congenial potential for multicolor imaging.