Limits...
Increased cellular uptake of biocompatible superparamagnetic iron oxide nanoparticles into malignant cells by an external magnetic field.

Prijic S, Scancar J, Romih R, Cemazar M, Bregar VB, Znidarsic A, Sersa G - J. Membr. Biol. (2010)

Bottom Line: SPIONs, dispersed in 0.9% NaCl solution, resulted in a stable ferrofluid at physiological pH for several months.Exposure to neodymium-iron-boron magnets significantly increased the cellular uptake of SPIONs, predominantly into malignant cells.Their cellular uptake was dependent on the cell type, and their accumulation within the cells was dependent on the duration of exposure to an external magnetic field.

View Article: PubMed Central - PubMed

Affiliation: Kolektor Group, Nanotesla Institute, Stegne 29, 1521, Ljubljana, Slovenia. sara.prijic@nanotesla.si

ABSTRACT
Superparamagnetic iron oxide nanoparticles (SPIONs) are used as delivery systems for different therapeutics including nucleic acids for magnetofection-mediated gene therapy. The aim of our study was to evaluate physicochemical properties, biocompatibility, cellular uptake and trafficking pathways of the custom-synthesized SPIONs for their potential use in magnetofection. Custom-synthesized SPIONs were tested for size, shape, crystalline composition and magnetic behavior using a transmission electron microscope, X-ray diffractometer and magnetometer. SPIONs were dispersed in different aqueous media to obtain ferrofluids, which were tested for pH and stability using a pH meter and zetameter. Cytotoxicity was determined using the MTS and clonogenic assays. Cellular uptake and trafficking pathways were qualitatively evaluated by transmission electron microscopy and quantitatively by inductively coupled plasma atomic emission spectrometry. SPIONs were composed of an iron oxide core with a diameter of 8-9 nm, coated with a 2-nm-thick layer of silica. SPIONs, dispersed in 0.9% NaCl solution, resulted in a stable ferrofluid at physiological pH for several months. SPIONs were not cytotoxic in a broad range of concentrations and were readily internalized into different cells by endocytosis. Exposure to neodymium-iron-boron magnets significantly increased the cellular uptake of SPIONs, predominantly into malignant cells. The prepared SPIONs displayed adequate physicochemical and biomedical properties for potential use in magnetofection. Their cellular uptake was dependent on the cell type, and their accumulation within the cells was dependent on the duration of exposure to an external magnetic field.

Show MeSH

Related in: MedlinePlus

TEM images of SPIONs. a Darker spherical area represents the core of a single nanoparticle measuring approximately 8 nm in diameter (arrows), coated with an approximately 2-nm-thick shell of silica on the surface (double arrow). SPIONs not autoclaved (b) resembled those after autoclaving (c). Samples for TEM observations were prepared by placing ultrasonically agitated suspension onto lacy carbon-coated nickel grids. When drying, SPIONs tend to form agglomerates due to their high surface energy
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2914263&req=5

Fig1: TEM images of SPIONs. a Darker spherical area represents the core of a single nanoparticle measuring approximately 8 nm in diameter (arrows), coated with an approximately 2-nm-thick shell of silica on the surface (double arrow). SPIONs not autoclaved (b) resembled those after autoclaving (c). Samples for TEM observations were prepared by placing ultrasonically agitated suspension onto lacy carbon-coated nickel grids. When drying, SPIONs tend to form agglomerates due to their high surface energy

Mentions: Size and shape of SPIONs, as determined by TEM analysis, demonstrated spherical core shell-type nanoparticles. The particle size was estimated to be 12 nm in diameter (11.60 ± 1.48 nm), with the iron oxide core being 8 nm and the silica coating 2 nm (Fig. 1). Ferrofluids used in biomedical applications have to be sterile. Sterilization of the ferrofluid by autoclaving did not change the size and shape of the SPIONs (Fig. 1).Fig. 1


Increased cellular uptake of biocompatible superparamagnetic iron oxide nanoparticles into malignant cells by an external magnetic field.

Prijic S, Scancar J, Romih R, Cemazar M, Bregar VB, Znidarsic A, Sersa G - J. Membr. Biol. (2010)

TEM images of SPIONs. a Darker spherical area represents the core of a single nanoparticle measuring approximately 8 nm in diameter (arrows), coated with an approximately 2-nm-thick shell of silica on the surface (double arrow). SPIONs not autoclaved (b) resembled those after autoclaving (c). Samples for TEM observations were prepared by placing ultrasonically agitated suspension onto lacy carbon-coated nickel grids. When drying, SPIONs tend to form agglomerates due to their high surface energy
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2914263&req=5

Fig1: TEM images of SPIONs. a Darker spherical area represents the core of a single nanoparticle measuring approximately 8 nm in diameter (arrows), coated with an approximately 2-nm-thick shell of silica on the surface (double arrow). SPIONs not autoclaved (b) resembled those after autoclaving (c). Samples for TEM observations were prepared by placing ultrasonically agitated suspension onto lacy carbon-coated nickel grids. When drying, SPIONs tend to form agglomerates due to their high surface energy
Mentions: Size and shape of SPIONs, as determined by TEM analysis, demonstrated spherical core shell-type nanoparticles. The particle size was estimated to be 12 nm in diameter (11.60 ± 1.48 nm), with the iron oxide core being 8 nm and the silica coating 2 nm (Fig. 1). Ferrofluids used in biomedical applications have to be sterile. Sterilization of the ferrofluid by autoclaving did not change the size and shape of the SPIONs (Fig. 1).Fig. 1

Bottom Line: SPIONs, dispersed in 0.9% NaCl solution, resulted in a stable ferrofluid at physiological pH for several months.Exposure to neodymium-iron-boron magnets significantly increased the cellular uptake of SPIONs, predominantly into malignant cells.Their cellular uptake was dependent on the cell type, and their accumulation within the cells was dependent on the duration of exposure to an external magnetic field.

View Article: PubMed Central - PubMed

Affiliation: Kolektor Group, Nanotesla Institute, Stegne 29, 1521, Ljubljana, Slovenia. sara.prijic@nanotesla.si

ABSTRACT
Superparamagnetic iron oxide nanoparticles (SPIONs) are used as delivery systems for different therapeutics including nucleic acids for magnetofection-mediated gene therapy. The aim of our study was to evaluate physicochemical properties, biocompatibility, cellular uptake and trafficking pathways of the custom-synthesized SPIONs for their potential use in magnetofection. Custom-synthesized SPIONs were tested for size, shape, crystalline composition and magnetic behavior using a transmission electron microscope, X-ray diffractometer and magnetometer. SPIONs were dispersed in different aqueous media to obtain ferrofluids, which were tested for pH and stability using a pH meter and zetameter. Cytotoxicity was determined using the MTS and clonogenic assays. Cellular uptake and trafficking pathways were qualitatively evaluated by transmission electron microscopy and quantitatively by inductively coupled plasma atomic emission spectrometry. SPIONs were composed of an iron oxide core with a diameter of 8-9 nm, coated with a 2-nm-thick layer of silica. SPIONs, dispersed in 0.9% NaCl solution, resulted in a stable ferrofluid at physiological pH for several months. SPIONs were not cytotoxic in a broad range of concentrations and were readily internalized into different cells by endocytosis. Exposure to neodymium-iron-boron magnets significantly increased the cellular uptake of SPIONs, predominantly into malignant cells. The prepared SPIONs displayed adequate physicochemical and biomedical properties for potential use in magnetofection. Their cellular uptake was dependent on the cell type, and their accumulation within the cells was dependent on the duration of exposure to an external magnetic field.

Show MeSH
Related in: MedlinePlus