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Updated: Aug 22, 2025
Polyethyleneimine-coated Iron Oxide Nanoparticles as a Vehicle for the Delivery of Small Interfering RNA to Macrophages In Vitro and In Vivo
Published on: February 5, 2019
Plasmid-DNA Delivery by Covalently Functionalized PEI-SPIONs as a Potential 'Magnetofection' Agent
René Stein1, Felix Pfister1, Bernhard Friedrich1
1Department of Otorhinolaryngology-Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kroener-Fresenius-Stiftung-Professorship, Universitätsklinikum Erlangen, 91054 Erlangen, Germany.
Superparamagnetic iron oxide nanoparticles (SPIONs) functionalized with polyethyleneimine (PEI) show high plasmid-DNA binding and efficient gene delivery. These novel nanoformulations offer a promising, non-cytotoxic magnetofection approach for cellular applications.
Area of Science:
- Biomedical Engineering
- Nanotechnology
- Gene Therapy
Background:
- Nanoformulations are crucial for nucleotide delivery in vaccinations and disease treatment.
- Local treatment strategies, like cancer therapy, require improved nanoparticle delivery concepts.
Purpose of the Study:
- To synthesize superparamagnetic iron oxide nanoparticles (SPIONs) for magnetofection.
- To functionalize SPIONs with polyethyleneimine (PEI) for enhanced plasmid-DNA complexation and cellular delivery.
Main Methods:
- SPIONs were synthesized and functionalized with an active catechol ester (CafPFP) to covalently bind PEI.
- Complexation of SPIONs with plasmid-DNA (pDNA) was analyzed for binding efficiency and particle properties.
- Transfection efficiency and cytotoxicity were evaluated in A375-M cells using a green fluorescent protein (GFP) sequence.
Main Results:
- Functionalized SPIONs (Caf-PEI-SPIONs) maintained nanosized properties (86 nm hydrodynamic size).
- 95% of pDNA strongly bound to SPIONs at a 2.5% pDNA/Fe weight ratio.
- A transfection efficiency of 3.5% was achieved with low pDNA amounts (10 ng), outperforming Lipofectamine (1.2%).
- The pDNA-SPION system exhibited no significant cytotoxicity.
Conclusions:
- Caf-PEI-SPIONs are effective nano-carriers for pDNA delivery via magnetofection.
- The system demonstrates high pDNA binding, efficient transfection, and low cytotoxicity.
- Further functionalization potential makes Caf-PEI-SPIONs promising for future therapeutic applications.
