Simple Synthesis of Water-Soluble Biological Carbon Quantum Dots as Drug Delivery Carriers for Undergraduates Experiments

Nanomaterials are one of the most popular and cutting-edge research topics in clinical biomedical fields as drug delivery carriers. Understanding and researching the nanomaterials used for drug delivery carriers are very significant for the undergraduates. Here, we introduce biological carbon quantum dots (Bio-CQDs) as drug delivery carriers into chemistry experiment curricula. Bio-CQDs have very high water solubility and high stability of their aqueous solution to electrolytes and heating, which is different from that of traditional nanomaterials. Students synthesize Bio-CQDs via a simple and rapid heating reaction at atmospheric pressure and purify them through solvent washing and filtration under reduced pressure. Then, they characterize and analyze the structural characteristics, optical properties, and water solubility of Bio-CQDs and compare the differences between the aqueous solution of Bio-CQDs and traditional nanomaterials to heating and electrolytes. Finally, after understanding the conjugated planar properties of Bio-CQDs, the students load the typical chemotherapy drug topotecan onto Bio-CQDs to demonstrate their potential for drug delivery carriers. In the entire process of the experiment, we emphasize the particularity of Bio-CQDs as drug delivery carriers in clinical applications and further demonstrate the advantages of Bio-CQDs as drug delivery platform. This comprehensive experimental course integrates physical chemistry knowledge into nanomaterials to demonstrate their important principles and biomedical applications.