Carbon dots (C-dots), a promising luminescent nanomaterial with exceptional physico-chemical properties gaining enormous attention in recent years. Carbon dots having enhanced biocompatibility and multiple routes of synthesis offers a promising substitute to luminescent quantum dots
(QD). Further, wavelength-controlled emission features of C-dots proved as a good candidate in the biolabeling applications. Herein, we are reporting a facile and one-step hydrothermal synthesis of biocompatible multi-color, Polyethyleneimine (PEI) surface passivated C-dots (CDP) from mint
leaves as a green source. The morphological and optical properties of C-dots have been extensively studied by Zeta-sizer, Transmission electron microscopy (TEM), X-ray diffraction (XRD) pattern, Ultra violet (UV)-visible spectroscopy and fluorescence spectroscopic analysis. Furthermore, Fourier
transform infrared (FT-IR) and X-Ray Photoelectron Spectroscopic (XPS) analysis have been performed for the understanding of surface states and chemical composition of C-dots. A comparative analysis in the biolabeling potentials of non-passivated C-dots (CD) and CDP was conducted in the breast
cancer (MCF-7) cells and the concentration dependent cytotoxicity was estimated. Further, an enhanced antioxidant property was showed by CDP as compared to CD. In the present study, a practical implication of C-dots synthesized from a herbal source (mint) to serve as a novel agent for various
biolabeling applications and antioxidant activity have been experimentally resolved. As synthesized CD and CDP can be, serve as better alternatives for imaging probe with improved biocompatibility.
Solvent Effects on Fluorescence Properties of Carbon Dots: Implications for Multicolor Imaging