Synthesis and biological assay of biopolymeric chitosan functionalized by phosphoramidic segment P(O)[NH-3Py]2 and its Cu(II), Ni(II) and Hg(II) complexes

Biopolymeric chitosan-phosphoramide (CPA) and its complexes of Cu(II), Ni(II) and Hg(II) were synthesized and characterized by techniques of FT-IR, elemental analysis (CHN), thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) and scanning electron microscope (SEM). The cytotoxicity of these compounds against breast MDA-MB-231 cell lines was assessed by MTT assay, where the CPA-Hg(II) complex with an IC50 of 95 ± 2 nM illustrated significant anticancer activity. Apoptotic cells were also studied by acridine orange/ethidium bromide (AO/EB) staining introducing the CPA-Hg(II) complex as a good agent to enhance apoptosis in MDA-MB-231 cell lines. Finally, the biological assays performed in this study show that CPA and its complexes exhibit a higher inhibition of cancer compared with chitosan, especially the CPA-Hg(II) and CPA-Cu(II) complexes.