{Reference Type}: Journal Article {Title}: A nanocarrier system based on CQDs for efficient mitoxantrone drug delivery. {Author}: Raeispour S;Rahmandoust M;Kouchakzadeh H; {Journal}: Heliyon {Volume}: 10 {Issue}: 11 {Year}: 2024 Jun 15 {Factor}: 3.776 {DOI}: 10.1016/j.heliyon.2024.e31674 {Abstract}: Cancer is the second most fatal disease among women. In recent years, utilizing strategies based on carbon quantum dots (CQDs) as targeted drug delivery systems has had a significant impact on advancing and improving cancer treatment. This study is focused on the development of a nanocarrier, based on CQDs, for improving the therapeutic efficiency of mitoxantrone (MTX). Hence, the N-doped CQDs were synthesized by a hydrothermal method. Following its purification, MTX was loaded to the CQD, resulting in an increase in the size from 36.78 ± 0.9 nm to 157.8 ± 12.18 nm, with an ideal drug entrapment efficiency of 97 %. Drug release investigation showed a pH-dependent improvement, from 8 % at pH 7.4 to 11 % at pH 5.2 after 48 h. Based on the Methylthiazolyldiphenyl-tetrazolium bromide (MTT) results after 5 h of treatment on MCF-7 breast cancer cells, the N-doped CQD showed no significant effect on the cancer cells, whereas a half maximal Inhibitory Concentration (IC50) was achieved with the N-doped CQD-MTX complex at a concentration between 0.5 to 0.8 μM. Therefore, the newly developed drug delivery complex was capable of providing a rather identical influence on MCF-7 cells, as the free MTX, however, improving the pharmacokinetic of the drug by its controlled and on-target drug release, due to an alteration in distribution and absorption parameters.