Microwave-Assisted Synthesis of Carbon Dot – Iron Oxide Nanoparticles for Fluorescence Imaging and Therapy

Abstract

Fluorescence microscopy is commonly used to image specific parts of a biological system, and is applicable for early diagnosis of cancer. Current fluorescent probes, such as organic dyes and quantum dots, suffer from poor solubility and high toxicity, respectively, demonstrating a need for a colloidal stable and non-toxic fluorescent probe. Here we present an iron oxide and carbon dot (CD) based nanoparticle (CNPCP) that displays optical properties similar to those of conventional fluorescent probe and also exhibits good biocompatibility. Fluorescent CDs were synthesized from glucosamine onto chitosan – polyethylene glycol (PEG) graft copolymer using microwave irradiation. These NPs were monodispersed in aqueous environments and displayed excitation-dependent fluorescence; they demonstrated good size stability and fluorescence intensity in biological media. In vitro evaluation of CNP as fluorescent probes in cancer cell lines showed that these NPs caused little toxicity, and allowed fast and quantitative imaging. Model therapeutic doxorubicin (DOX) was conjugated onto the NPs (CNPCP-DOX) to demonstrate the multifunctionality of the NPs, and in vitro studies showed that CNPCP-DOX was able to kill cancer cells in a dose dependent manner. These results indicate the potential of using CNPCPs as fluorescent probes capable of delivering chemotherapeutics.

Carbon Dots: Classification, Properties, Synthesis, Characterization, and Applications in Health Care—An Updated Review (2018–2021)

“…In another study using microwave irradiation, fluorescent CDs were prepared using glucosamine onto a PEG @ chitosan co-polymer layer. The resultant CDs could show excellent chemical stability, good fluorescence intensity, and excitation-dependent fluorescence in biological matrices [142].…”

Quantum Dots: An Emerging Approach for Cancer Therapy

“…Chung et al, used microwave irradiation to create fluorescent iron oxide and carbon dots-based nanoparticles for cancer cell fluorescence imaging and treatment. The use of these QDs as fluorescent probes in cancer cell lines revealed that they were less hazardous and allowed for quick and quantitative imaging (Chung and Zhang, 2021). Ma et al, designed a fluorescent probe for detecting protein tyrosine kinase 7 in the peripheral circulation using multi-carbon dots and an aptamer-based signal amplification ratiometric.…”

Synthesis of Fluorescent Sulfur Quantum Dots for Bioimaging and Biosensing

“…Traditional semiconductor QDs are composed of group II-VI or III-V elements and usually contain toxic heavy metal ions, greatly limiting their applications in biological and environmental fields. As such, the development of metal-free fluorescent QDs such as carbon QDs ( Chung and Zhang, 2021 ; Sun et al, 2006 ; Liao et al, 2016 ), graphene QDs ( Kalita et al, 2016 ; Zhou et al, 2017 ), and silicon QDs ( Warner et al, 2005 ) has attracted more and more attention.…”