Curcumin derived functional carbon quantum dots for enhanced tumor theranostic

Chinese herbal has been widely researched towards the treatment of disease in recent years. These natural products and the derivatives have demonstrated significant value with variety of pharmacodynamical effects. In this work, aiming to explore the application scenarios of Chinese herbal and enrich its functions, we developed the bottom-up synthetic strategy and prepared series of functional carbon quantum dots (CQDs) based on curcumin which extracted from Curcuma longa Linn. Cellular assays, including CCK8, transwell migration, invasion, and apoptotic assays, were performed to assess the biological effects of CCQD-1, CCDQ-2, CCDQ-3, and CCDQ-4. A xenograft mouse model was established to evaluate the effectivities of tumor inhibition in vivo. RNA sequencing was used to elucidate the molecular regulatory mechanisms of CCQDs. As expected, the carbonyl groups on curcumin facilitated the intermolecular cross-linking with amino-rich monomers by Schiff base reaction. Compared to the original curcumin, all of the curcumin-derived CQDs (CCQDs) possessed superior solubility in water and advanced biocompatibility, while inherited the fluorescent properties of CQDs and the apoptosis towards tumor cells of curcumin. Notably, the CCQDs could efficiently enter cells while stain and label the cytoplasm. Both in vitro and in vivo results confirmed that CCQDs could significantly eliminate tumor cells and inhibit the tumor growth. This work provided a successful showcase of modification and functionalization of Chinses herbal and highlighted the curcumin as a promising candidate for cancer theranostics.