<jats:title>Abstract</jats:title>
<jats:p>This research reports the synthesis of copper oxide nanoparticles (CuONP) functionalized by the polar monomers acrylonitrile (ACN) and methyl methacrylate (MMA). The synthesis was achieved by a practical exchange ligand reaction from CuONP previously stabilized by hexadecyltrimethylammonium bromide (CTAB). The replacement of CTAB by ACN or MMA produced the functionalized nanoparticles CuONP-ACN and CuONP-MMA, respectively. The functionalized nanoparticles were characterized by ultraviolet-visible spectroscopy (UV–vis), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (SEM), dynamic light scattering (DLS), Zeta potential, x-ray diffraction (XRD), high-resolution-transmission electron microscopy (HR-TEM), and selected area electron diffraction (SAED) analysis. Changes in surface plasmon resonance (SPR) band and the functional group bands observed in UV–vis and FTIR spectra confirmed the efficient replacement of CTAB by polar monomers. Moreover, CuONP-ACN and CuONP-MMA showed a negative surface charge with spherical morphology. X-ray diffraction (XRD) analysis showed that a monoclinic CuO crystal system was formed.</jats:p>