Multiwalled carbon nanotubes (MWCNTs) have gained a lot of multidisciplinary attention and biomedical applications such as drug delivery, because of their distinct physicochemical characteristics. Even though MWCNTs are not used because of low dispersibility in aqueous or non-aqueous medium. Functionalizing MWCNTs is an attractive way to overcome this drawback, it improves biocompatibility and promotes ligand attachment for targeted drug delivery. However, most functionalization techniques include hazardous procedures and costly chemicals. The current study uses a straightforward, economically advantageous method to functionalize MWCNTs with lysine through 1,3-dipolar cycloaddition for enhanced dispersibility and to offer a ligand anchoring ε-amino group for targeted delivery to breast cancer. MWCNTs had been functionalized with lysine and sugar moieties ligands (galactose/mannose) to create efficient nanocarriers that can bind to lectin receptors in MDA-MB-231 or MCF-7 cancer cells. Doxorubicin (Dox) was loaded into the ligands conjugated MWCNTs. In comparison to pristine MWCNTs, 1,3-lysinated MWCNTs conjugated with ligands demonstrated enhanced dispersion in an aqueous medium and greater drug loading capacity. Drug release studies in pH 7.4 were 20% only & in pH 5.0 was around 75%. Dox-loaded MWCNTs provided pH-dependent releases and enhanced Dox accumulation inside the cancer cells, as evidenced by higher inhibition of MDA-MB-231 or MCF-7 compared to plain Dox, and unloaded Dox MWCNTs nanoformulations provided negligible cytotoxicity. Based on the results, MWCNTs functionalized with lysine by 1,3-dipolar cycloaddition offer promising nontoxic nanoplatforms with improved aqueous dispersibility and potential for conjugation with ligands for targeted delivery of Dox to breast cancer cells.