Bacterial adherence to the cellular and inert substrate in the presence of CoFe2O4 and Fe3O4 /oleic acid – core/shell.


Mariana Carmen Chifiriuc, Veronica Lazǎr, Coralia Bleotu, Ioana Cǎlugǎrescu, Alexandru Mihai Grumezescu*, Dan Eduard Mihaiescu, Diana Elena Mogoşanu, Alice Sandra Buteicǎ, Elena Buteicǎ: Bacterial adherence to the cellular and inert substrate in the presence of CoFe2O4 and Fe3O4 /oleic acid – core/shell.Digest Journal of Nanomaterials and Biostructures, 6(1):37-42, 2011.


The purpose of the present work is the in vitro assay of the efficiency of magnetic nanoparticles of CoFe2O4 and Fe3O4/oleic acid – core/shell against bacterial adherence to cellular and acellular substrata and against bacterial biofilm formation. Magnetic nanoparticles have been synthesized by Massart method with oleic acid as the surfactant, under domestic microwave conditions. The dimensions of Fe3O4 and CoFe2O4 nanoparticles were in the 5-20 nm range and they were characterized by High Resolution Transmision Electron Microscopy. The adherence assays were performed on Gram negative (Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa) and Gram-positive (Staphylococus aureus, Entereococcus faecalis) bacterial strains as well as on yeasts (Candida albicans). Our results showed that the magnetic nanoparticles of CoFe2O4 and Fe3O4 / oleic acid – core/shell exhibit specific influences on the ability of different microbial strains to colonize the cellular and inert substrata. They either stimulate or inhibit this hallmark of microbial virulence, depending on the tested nanoparticles composition and the tested strain. It is to be mentioned that both types of nanoparticles have produce a strong inhibitory effect on the adherence to the cellular substrate of S. aureus and C. albicans strains, pathogens frequently implicated in the human pathology and in the etiology of biofilm associated infections. These results are leading us to the hypothesis that magnetic nanoparticles could be used for the development of novel antimicrobial materials or strategies for fighting medical biofilms.