Effect of superparamagnetic iron oxide nanoparticles on fluidity and phase transition of phosphatidylcholine liposomal membranes.
Superparamagnetic iron oxide nanoparticles (SPIONs) with multifunctional properties have shown great promise in theranostics. The aim of our work was to compare the effects of SPIONs on the fluidity and phase transition of the liposomal membranes prepared with zwitterionic phosphatidylcholine lipids. In order to study if the surface modification of SPIONs has any influence on these membrane properties, we have used four types of differently functionalized SPIONs, such as: plain SPIONs (primary size was shown to bê11 nm), silica-coated SPIONs, SPIONs coated with silica and functionalized with positively charged amino groups or negatively charged carboxyl groups (the primary size of all the surface-modified SPIONs was ~20 nm). Small unilamellar vesicles prepared with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine lipids and multilamellar vesicles prepared with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine lipids were encapsulated or incubated with the plain and surface-modified SPIONs to determine the fluidity and phase transition temperature of the bilayer lipids, respectively. Fluorescent anisotropy and differential scanning calorimetric measurements of the liposomes that were either encapsulated or incubated with the suspension of SPIONs did not show a significant difference in the lipid ordering and fluidity; though the encapsulated SPIONs showed a slightly increased effect on the fluidity of the model membranes in comparison with the incubated SPIONs. This indicates the low potential of the SPIONs to interact with the nontargeted cell membranes, which is a desirable factor for in vivo applications.
Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Slovenia.
Poornima Budime
PB
Santhosh
Department of Biology, Biotechnical Faculty, University of Ljubljana, Slovenia.
Barbara
B
Drašler
Department of Biology, Biotechnical Faculty, University of Ljubljana, Slovenia.
Damjana
D
Drobne
Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, Slovenia.
Mateja Erdani
ME
Kreft
Department for Materials Synthesis, Jožef Stefan Institute, Slovenia.
Slavko
S
Kralj
Department for Materials Synthesis, Jožef Stefan Institute, Slovenia.
Darko
D
Makovec
Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Slovenia ; Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Ljubljana, Slovenia.
Nataša Poklar
NP
Ulrih
D002152:Calorimetry, Differential Scanning; D003911:Dextrans / Q000737:chemistry*; D005454:Fluorescence Polarization; D008051:Lipid Bilayers / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008560:Membrane Fluidity / Q000187:drug effects*; D053758:Nanoparticles / Q000737:chemistry*; D044367:Phase Transition / Q000187:drug effects*; D010713:Phosphatidylcholines / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry
D003911:Dextrans; D008051:Lipid Bilayers; D008081:Liposomes; D058185:Magnetite Nanoparticles; D010713:Phosphatidylcholines; D012822:Silicon Dioxide; C065507:ferumoxides; C028694:1-palmitoyl-2-oleoylphosphatidylcholine
encapsulated SPIONs; incubated SPIONs; membrane integrity; phase behavior; zwitterionic liposomes