Engineering Mitochondriotropic Carbon Dots for Targeting Cancer Cells

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cell Biology

Background:

• Carbon dots (CDs) are promising nanomaterials for bioimaging.
• Targeting specific cellular organelles like mitochondria remains a challenge.
• Developing non-toxic, biocompatible probes is crucial for in vitro and in vivo applications.

Purpose of the Study:

• To synthesize and functionalize nitrogen-doped carbon dots (CDs) for enhanced cellular membrane transport.
• To achieve precise subcellular organelle targeting, particularly mitochondria.
• To evaluate the biocompatibility, non-cytotoxicity, and imaging capabilities of functionalized CDs.

Main Methods:

• One-step microwave-assisted pyrolysis of citric acid and ethylenediamine to create nitrogen-doped CDs.
• Functionalization of CDs with alkylated triphenylphosphonium groups of varying alkyl chain lengths.
• Further modification with rhodamine B for enhanced fluorescence imaging.
• In vitro cell experiments using normal and cancer cell lines.

Main Results:

• Optimized nitrogen-doped CDs demonstrated efficient cell membrane penetration.
• Functionalized CDs exhibited selective localization in lysosomes or mitochondria based on design.
• Rhodamine B conjugation enhanced fluorescence imaging sensitivity, allowing low-concentration use.
• Successful mitochondrial targeting was achieved by tuning alkyl chain length and functionalization degree.
• CDs showed non-cytotoxicity and biocompatibility in both normal and cancer cells.
• Selective uptake in cancer cells was observed due to higher transmembrane potential.

Conclusions:

• Carefully designed carbon dots can achieve precise mitochondrial targeting.
• Functionalized CDs offer excellent biocompatibility and non-cytotoxic properties.
• These CDs hold significant potential for advanced bioimaging and selective cancer cell uptake.