Green Synthesis of Blue-Emitting Graphene Oxide Quantum Dots for In Vitro CT26 and In Vivo Zebrafish Nano-Imaging as Diagnostic Probes

Govinda Gorle; Ganesh Gollavelli; Gowreeswari Nelli; Yong-Chien Ling

doi:10.3390/pharmaceutics15020632

Green Synthesis of Blue-Emitting Graphene Oxide Quantum Dots for In Vitro CT26 and In Vivo Zebrafish Nano-Imaging as Diagnostic Probes

Pharmaceutics. 2023 Feb 13;15(2):632. doi: 10.3390/pharmaceutics15020632.

Authors

Govinda Gorle¹, Ganesh Gollavelli^{2

3}, Gowreeswari Nelli⁴, Yong-Chien Ling¹

Affiliations

¹ Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan.
² Department of Humanities and Basic Sciences, Aditya Engineering College, Surampalem 533437, India.
³ Jawaharlal Nehru Technological University, Kakinada 533003, India.
⁴ Department of Chemistry, Andhra University, Visakhapatnam 530003, India.

Abstract

Graphene oxide quantum dots (GOQDs) are prepared using black carbon as a feedstock and H₂O₂ as a green oxidizing agent in a straightforward and environmentally friendly manner. The process adopted microwave energy and only took two minutes. The GOQDs are 20 nm in size and have stable blue fluorescence at 440 nm. The chemical characteristics and QD morphology were confirmed by thorough analysis using scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscope (AFM), Fourier transmission infra-red (FT-IR), and X-ray photoelectron spectroscopy (XPS). The biocompatibility test was used to evaluate the toxicity of GOQDs in CT26 cells in vitro and the IC₅₀ was found to be 200 µg/mL with excellent survival rates. Additional in vivo toxicity assessment in the developing zebrafish (Danio rerio) embryo model found no observed abnormalities even at a high concentration of 400 μg/mL after 96 h post fertilization. The GOQDs luminescence was also tested both in vitro and in vivo. They showed excellent internal distribution in the cytoplasm, cell nucleus, and throughout the zebrafish body. As a result, the prepared GOQDs are expected to be simple and inexpensive materials for nano-imaging and diagnostic probes in nanomedicine.

Keywords: diagnostic probes; graphene oxide; green synthesis; nano-imaging agents; quantum dots.

Grants and funding

This research was partially supported by the Ministry of Science and Technology, Taiwan, ROC. under Grant No. MOST 104-2113-M-007-008-MY3. Any opinions, findings, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the MOST.