A sustainable green synthesis of functionalized biocompatible carbon quantum dots from Aloe barbadensis Miller and its multifunctional applications.

Abstract

Herein, we demonstrated a sustainable green approach for the preparation of fluorescent biocompatible carbon quantum dots by microwave-assisted reflux synthesis from Aloe barbadensis Miller (Aloe vera) extract. The Transmission Electron Microscopic images reveal that the as-prepared CQDs are spherical with less than 5 nm in size. The CQDs are amorphous, showed an excitation-independent behaviour, emitted blue fluorescence and have a fluorescence quantum yield of 31%. The presence of -OH groups contributed to the blue emission and helped CQDs to disperse uniformly in an aqueous solution. The prepared CQDs were employed as a photocatalyst for the environmental remediation to degrade the anionic dye, eosin yellow under visible light irradiation. The results showed that the CQDs exhibited excellent photocatalytic efficiency of 98.55% within 80 min and a 100% efficiency within 100 min. Further, the cytotoxic properties of as-prepared CQDs are investigated in the MCF-7 breast cancer cell line using MTT assay. The results demonstrated a notable reduction in cell viability in a dose-subjected manner, and the cell viability decreased to 50% (IC50) at a concentration of 52.2 ± 1.35 μg/mL. Furthermore, cellular internalization of CQDs in breast cancer cells is studied. As expected, CQDs are found to internalize by the cancer cells with blue emission as revealed by fluorescence microscope. In the end, CQDs in human breast cancer cells demonstrate the anti-proliferative effect and are found to be an impressive fluorescent probe for live-cell imaging, paving a path for its potential biomedical applications.

• Authors: Jalaja Prasad Malavika, Chellappan Shobana, Murugesan Ragupathi, Ponnuchamy Kumar, Yun Sung Lee, Muthusamy Govarthanan, Ramakrishnan Kalai Selvan
• Journal: Environmental research (Environ Res) Vol. 200 Pg. 111414 (09 2021) ISSN: 1096-0953 [Electronic] Netherlands
• PMID: 34052245 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2021 Elsevier Inc. All rights reserved.

Chemical References

• Fluorescent Dyes
• Carbon

Topics

• Aloe
• Carbon
• Fluorescent Dyes
• Humans
• Microscopy, Electron, Transmission
• Quantum Dots (toxicity)