Cellular interaction of different forms of aluminium nanoparticles in rat alveolar macrophages

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Abstract:

Materials: The materials, aluminium oxide nanoparticles (30 nm, 40 nm) and aluminium nanoparticles with a 2-3 nm oxide coat (50 nm, 80 nm, 120 nm), were synthesized NovaCentrix, Austin, TX.

The physical parameters such as size (of the primary materials and in dispersion) and zeta potential of the different materials in different solutions (conc, media) were characterised, using Transmission Electron Microscopy (TEM), Dynamic Light Scattering Analysis (DLS) and Laser Doppler Velocimetry (LDV).

The viabililty of the NR8383 macrophages was assessed with the MTT assay, the inhibition of the phagcytotic capacity was scored as the PI after incubation with 2 µm latex beads.

All used nanomaterials significantly agglomerated in suspension. The larger the particles (and the higher the concentration), the larger the agglomerates. The viability of the NR8383 cells remains high in the presence of Al-ox-NP (25 – 100 µg/ml) while results from Al-NP show toxicity at 25 µg/ml). Phagocytosis is more inhibited by Al-NP compared to Al-ox-NP.

The reason why we choose this paper is because it describes not only biological effect but also some physico-chemical characteristics were studied (and found e.g. that the size set by the producer was not accurate). This is the type of research is needed to build a comprehensive database on health and/or toxic effects of nanomaterials. The authors try to link chemical composition and size to the final biological effects.

Notes:

In this focused study, the authors examined the interaction of nanosized aluminium oxide (Al-ox-NP) and aluminium (Al-NP) with phagocytitic cells (rat alveolar macrophages - NR8383). The reported effects on cell viability and on the phagocytic capacity of the macrophages are referred to based on the particle size and the particle’s chemical composition.

Although all studied particles have the same surface chemical composition (Al-oxide) in contact with the cells in cultures, the toxic effects (cytotoxicity and the reduction of the phagocytic capacity) of the Al-NP were significant higher than those fully oxidized Al-NP. The toxicity and loss of macrophage phagocytic function data did not follow NP-size of these chemically different particles. The researchers used good experimental design to assess several critical physical parameters, among which included size and surface charateristics.. for these material studied, it was found that nanoparticles differed not only in response due to size but also links of biological effects to surface physical charateristics and composition.