Physicochemical and biological interactions between cerium oxide nanoparticles and a 1,8-naphthalimide derivative

Abstract

Cerium (Ce) oxide nanoparticles (CNPs) have attracted attention due to their high bioactivity and unique redox-chemistry. The oxygen vacancies at the surface of the nanoparticle explain the autocatalytic properties of CNPs in which the Ce atoms occupy the center of the oxygen vacancies surrounded by Ce atoms. Until now, CNPs have been associated with organic molecules at the synthesis stage to extend their applications or improve their stability. However, there is a lack of information regarding the post-synthesis interaction of CNPs and organic molecules that could enhance or induce new properties. Due to their unique optical properties and their many uses in different areas such as supramolecular chemistry or biomedicine, we have chosen a derivative from the family of naphthalimides (the 4-amino-1,8-naphthalimide-N-substituted; ANN) to study the interaction with different CNPs (CNP1-4) and their joint bioactivity compared to that of the same compounds alone. ANN-CNP complexes were formed as revealed by spectroscopic studies, but, the interaction was markedly different depending on the physicochemical properties of CNPs and their surface content of Ce sites. The ANN adsorption on all CNPs involved the amino group in the naphthalene moiety as shown by NMR spectroscopy, while the pyrrolidine ring was mainly involved in the specific interaction between ANN and CNP1. The biological effect of each CNP and ANN individually and forming complexes was assessed using a bioluminescent model bacterium. The results showed that ANN and CNP with the higher content of surface Ce (CNP1) when combined acted additively towards the used model organism. In the opposite, ANN-CNP2, ANN-CNP3 and ANN-CNP4 complexes were antagonistic when the nanoparticles dominated the mixture. The results of this study contribute to expand the knowledge of the interaction between nanoparticles and organic molecules which may be useful for understanding the behavior of nanoparticles in complex matrices.

Mechanism of the toxic action of cationic G5 and G7 PAMAM dendrimers in the cyanobacteriumAnabaenasp. PCC7120

“…PCC7120 (hereinafter, Anabaena) was selected as a model organism, given its environmental relevance and ubiquity, as well as the extensive bibliography regarding the genetic, physiology and ecological importance. Furthermore, this cyanobacterium has been used regularly as model for ecotoxicological studies, including the field of nanotoxicology 31,[33][34][35][36][37][38][39][40] .…”

Elucidating the Molecular Structure of Hydrophobically Modified Polyethylenimine Nanoparticles and Its Potential Implications for DNA Binding

“…The comparative ATR-FTIR spectra for the NPEI product and b-PEIs in the 950–1900 cm –1 region are shown in Figure S2 (Table S6). The occurrence of C–N stretching bands in the NPEI product in the wavenumber range of 1349–1381 cm –1 represents dicarboximide formation . The presence of imide (CO) stretching modes (symmetric stretch, 1655 cm –1 ; asymmetric stretch, 1697 cm –1 ) evidently validates the occurrence of the modification of PEI amine groups by NA moieties. , The solubility of the compound was initially checked in various solvents such as pristine water, methanol, acetonitrile, DMSO, tetrahydrofuran, and acetic acid.…”

Use of Cyanobacterial Luminescent Bioreporters to Report on the Environmental Impact of Metallic Nanoparticles

“…General toxicity of metallic NPs was evaluated by the exposure of Nostoc CPB4337 to increasing metallic NP concentrations. This bioreporter strain has been previously used to assess NPs toxicity [37,38,39,49]. The calculated IC 50 indicated ZnNPs and AgNPs as the most toxic metallic NPs tested.…”