Cellular uptake of magnetic nanoparticle is mediated through energy-dependent endocytosis in A549 cells

Abstract

Biocompatible silica-overcoated magnetic nanoparticles containing an organic fluorescence dye, rhodamine B isothiocyanate (RITC), within a silica shell [50 nm size, MNP@SiO2(RITC)s] were synthesized. For future application of the MNP@SiO2(RITC)s into diverse areas of research such as drug or gene delivery, bioimaging, and biosensors, detailed information of the cellular uptake process of the nanoparticles is essential. Thus, this study was performed to elucidate the precise mechanism by which the lung cancer cells uptake the magnetic nanoparticles. Lung cells were chosen for this study because inhalation is the most likely route of exposure and lung cancer cells were also found to uptake magnetic nanoparticles rapidly in preliminary experiments. The lung cells were pretreated with different metabolic inhibitors. Our results revealed that low temperature disturbed the uptake of magnetic nanoparticles into the cells. Metabolic inhibitors also prevented the delivery of the materials into cells. Use of TEM clearly demonstrated that uptake of the nanoparticles was mediated through endosomes. Taken together, our results demonstrate that magnetic nanoparticles can be internalized into the cells through an energy-dependent endosomal-lysosomal mechanism.

The intensity of internalization and cytotoxicity of superparamagnetic iron oxide nanoparticles with different surface modifications in human tumor and diploid lung cells

“…Suppression of MNPs uptake into A549 cell at low temperature has observed also Kim et al [7]. It is supposed that the particle size determines the mechanism of nanoparticle entrance into cells [40].…”

“…However, the data published so far lack concordance about the threshold diameter which determines the particular endocytotic pathway involved in particle internalization [41]. Using the specific metabolic inhibitors it has been shown that magnetite nanoparticles of the hydrodynamic size around 80 nm are internalized by clathrin-mediated endocytosis [7,42]. Further experiments are required to determine the precise mechanism(s) of cellular uptake of particular coated MNPs used in this study.…”

“…To prevent MNPs aggregation, the surface of nanoparticles has to be modified (coated) with various surfactants, metals or natural and synthetic polymers [7][8][9]. Coating increases the colloidal stability of nanoparticles, the blood circulation half-life, biocompatibility, and internalization efficiency and decreases the toxicity of particles.…”

Differences in Magnetic Particle Uptake by CNS Neuroglial Subclasses: Implications for Neural Tissue Engineering

“…Most work to date evaluating cellular MP uptake and handling has utilized cell lines [34][35][36][37][38]. This risks chronic contamination by mycoplasma -such 'cryptic' contamination can alter cell structure, metabolism and growth, all of which can impact the interpretation of data [42].…”

An efficient Trojan delivery of tetrandrine by poly(N-vinylpyrrolidone)-block-poly(ε-caprolactone) (PVP-b-PCL) nanoparticles shows enhanced apoptotic induction of lung cancer cells and inhibition of its migration and invasion

“…This endocytic process can be significantly influenced by temperature and blocked by the endocytosis inhibitor NaN 3 . 38 It is demonstrated in both our current and previous studies that the uptake of Tet-NPs is mainly mediated by endocytosis, a kind of transportation mechanism which is more efficient than the cellular uptake of free drug by filtration, thereby leading to the enhanced cytotoxicity of Tet-NPs. 25 …”