ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Co-assembly of zwitterionic surfactant-like peptides with fatty acids at the solid–liquid interface of magnetic nanoparticles improves their water dispersibility, morphology, and size distribution

Marzieh Ferdosian, Hamid Reza Madaah Hosseini, Loghman Firoozpour, Mohammad Ali Shokrgozar, and Nasir Mohajel

Department of National Cell Bank, Pasteur Institute of Iran, Tehran, Iran

E-mail: mashokrgozar@pasteur.ac.ir

Received: 25 August 2024  Accepted: 19 November 2024

Abstract:

The potential of Fe₃O₄ nanoparticles (NPs) can only be fully realized when highly stable water-dispersible particles with narrow particle size distribution and uniform morphology are produced in a simple sustainable and scalable process. Fatty acids have been successfully utilized as surfactants in the coprecipitation process to produce hydrophobic Fe₃O₄ NPs with desirable properties, which need additional processing to render them hydrophilic. In this study, an innovative single-step process was introduced for coating Fe₃O₄ NPs using two surfactant-like peptides, AC-A6K^± and NH2-A6K^± (^±; refers to the coexisting positive and negative charge at the C-terminal of the peptides). This simplified process involves a single-step co-assembly of these peptides with aliphatic chains of palmitic acid (PA) at the surface of the Fe₃O₄ NPs. The impact of these modifications on the physicochemical properties of Fe₃O₄ NPs was thoroughly investigated, revealing that the peptide-coated particles exhibited enhanced dispersibility in aqueous environments, a more uniform morphology, nearly neutral zeta potential, and reduced aggregation, resulting in smaller and more uniform particles, when compared to lipid-stabilized NPs (Fe₃O₄ ^PA). Furthermore, the Fe₃O₄ ^PA NPs that were coated with AC-A6K^± peptide (Fe₃O₄ ^{PA/AC−A6K±}) demonstrated superior coating efficiency and a more favorable particle size distribution than those coated with A6K^± (Fe₃O₄ ^PA/A6K±). Notably, the crystal structure and magnetic saturation of the Fe₃O₄ ^PA NPs were preserved even after being assembled with AC-A6K^± peptide. Our observations suggest that coating fatty acid-stabilized Fe₃O₄ NPs with surfactant-like peptides by a one-step co-assembly process is feasible and can produce magnetic nanoparticles (MNPs) with potential clinical application.

Graphical abstract

Keywords: Magnetic nanoparticles; Surfactant-like peptide; Co-assembly process; Peptide-coating

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03821-8

Chemical Papers 79 (2) 847–857 (2025)