Carboxymethyl-Dextran-Coated Superparamagnetic Iron Oxide Nanoparticles for drug Delivery: Influence of the Coating Thickness on the Particle Properties

Chiara Turrina, Davide Milani, Anna Klassen, Diana M. Rojas-González, Jennifer Cookman, Matthias Opel, Barbara Sartori, Petra Mela, Sonja Berensmeier, Sebastian P. Schwaminger*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Carboxymethyl-dextran (CMD)-coated iron oxide nanoparticles (IONs) are of great interest in nanomedicine, especially for applications in drug delivery. To develop a magnetically controlled drug delivery system, many factors must be considered, including the composition, surface properties, size and agglomeration, magnetization, cytocompatibility, and drug activity. This study reveals how the CMD coating thickness can influence these particle properties. ION@CMD are synthesized by co-precipitation. A higher quantity of CMD leads to a thicker coating and a reduced superparamagnetic core size with decreasing magnetization. Above 12.5–25.0 g L −1 of CMD, the particles are colloidally stable. All the particles show hydrodynamic diameters < 100 nm and a good cell viability in contact with smooth muscle cells, fulfilling two of the most critical characteristics of drug delivery systems. New insights into the significant impact of agglomeration on the magnetophoretic behavior are shown. Remarkable drug loadings (62%) with the antimicrobial peptide lasioglossin and an excellent efficiency (82.3%) were obtained by covalent coupling with the EDC/NHS (N-ethyl-N′-(3-(dimethylamino)propyl)carbodiimide/N-hydroxysuccinimide) method in comparison with the adsorption method (24% drug loading, 28% efficiency). The systems showed high antimicrobial activity with a minimal inhibitory concentration of 1.13 µM (adsorption) and 1.70 µM (covalent). This system successfully combines an antimicrobial peptide with a magnetically controllable drug carrier.

Original languageEnglish
Article number14743
JournalInternational Journal of Molecular Sciences
Issue number23
Publication statusPublished - Dec 2022


  • carboxymethyl dextran
  • iron oxide nanoparticles
  • antimicrobial peptide
  • magnetically controlled drug delivery
  • agglomeration behavior

ASJC Scopus subject areas

  • Materials Chemistry
  • Molecular Biology
  • Spectroscopy
  • Catalysis
  • Inorganic Chemistry
  • Computer Science Applications
  • Physical and Theoretical Chemistry
  • Organic Chemistry

Fields of Expertise

  • Advanced Materials Science


  • BioTechMed-Graz

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