Milk-derived multi-fluorescent graphene quantum dot-based cancer theranostic system

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Graphene quantum dots (GQDs) offer unique optical and electronic properties for biomedical applications.
• Developing cost-effective and sustainable synthesis methods for GQDs is crucial for their clinical translation.
• Cancer theranostics require agents that can simultaneously diagnose and treat the disease.

Purpose of the Study:

• To synthesize aqueous-soluble, multi-fluorescent GQDs from cow milk using a green chemistry approach.
• To functionalize GQDs with an anti-cancer drug for targeted delivery and evaluate their theranostic potential in vitro.
• To investigate the imaging and therapeutic capabilities of the synthesized GQDs for cancer applications.

Main Methods:

• One-pot microwave-assisted synthesis of GQDs from cow milk.
• Characterization of GQDs using X-ray photoelectron spectroscopy (XPS) and microscopy.
• Drug loading of berberine hydrochloride (BHC) onto GQDs via cysteamine hydrochloride (Cys) linkage.
• In vitro cytotoxicity assays (Trypan blue, MTT) and cellular bioimaging (CLSM, fluorescence microscopy).

Main Results:

• Synthesized spherical, multi-fluorescent GQDs (ca. 5nm) with N-doping and oxygen-rich composition.
• Achieved high drug loading efficiency (ca. 88%) for BHC onto GQDs@Cys-BHC complex.
• Demonstrated significant cytotoxic effects of GQDs@Cys-BHC on HeLa and MDA-MB-231 cancer cell lines.
• Successfully performed multi-excitation cellular bioimaging using the theranostic complex.

Conclusions:

• Economical and green synthesis of GQDs from cow milk is feasible for theranostic applications.
• The GQDs@Cys-BHC complex exhibits promising in vitro therapeutic efficacy and diagnostic imaging capabilities.
• This approach holds potential for developing novel theranostic agents for cancer therapy.