Nitrogen-doped carbon dots for doxorubicin-targeted delivery and two-photon cell imaging

Nitrogen (N) doped CDs (N-CDs) were prepared using citric acid and hexamethylenete-tramine by a one-step hydrothermal method, characterized by transmission electron microscopy (TEM), Powder X-ray Diffractometer (PXRD), Nuclear Magnetic Resonance (13C NMR), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), and ultraviolet-visible (UV-vis) absorption spectra. The doping mechanism and drug-loading characteristics of N-CDs were also studied. The results showed that N-CDs had both down-and up-conversion fluorescence properties and the average particle size was about 4.28 nm. N-CDs could be used as a drug carrier for doxorubicin (DOX) (N-CDs-DOX) via the formation of the -N=C-bond, and the drug-loading rate of N-CDs-DOX was 35.88%. The N-CDs-DOX had pH-targeted properties and low cytotoxicity. In vitro release of N-CDs-DOX belonged to the Weibull model and Fick diffusion. The results showed that N-CDs could deliver DOX successfully, and collocate with DOX in the SH-SY5Y cells through two-photon imaging. The N-CDs-DOX system had sustained-release and pH-targeted properties. N-CDs were expected to deliver a type of drugs containing-C=O group and be used in cancer treatment.& COPY; 2023 Hebei Normal University. Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Nitrogen-doped carbon dots (N-CDs) were synthesized via a one-step hydrothermal method using citric acid and hexamethylenete-tramine. The N-CDs exhibited both down- and up-conversion fluorescence properties with an average particle size of 4.28 nm. These N-CDs were used as a drug carrier for doxorubicin (DOX) with a drug-loading rate of 35.88%. The N-CDs-DOX system displayed sustained-release and pH-targeted properties.