Effects of Micro/Nano Particle Size on Cell Function and Morphology

Abstract

The cytotoxicity of micro/nano particles in Ti, TiO and carbon nanotube was investigated by in vitro biochemical analyses using human neutrophils. The particles smaller and larger than the neutrophils were used to determine the relationship between cell and particle size with respect to cytotoxicity. As the particle size decreased, the cell survival rate was decreased and, with the good corresponding relation to this, the value of lactate dehydrogenase (LDH), which is the indication of cell disruption, was increased. The release of superoxide anion showed the increasing tendency. Proinflammatory cytokines were detected distinctly for 3µm or smaller particles and very little in more than 10µm, which is closely related to the phagocytosis by neutrophils. ICP elemental analysis showed that the dissolution from Ti particles was below detection limit. Micro and nano particles stimulated the cell reactions according to the results of the human neutrophil functional tests. As the particle size was smaller, the inflammation was pronounced. The fine particles less than 3µm caused distinctly the inflammation in the surrounding tissue. All these results indicated that the cytotoxicity was induced due to the physical size effect of particles, which is different from the ionic dissolution effect. The clinical phenomenon confirmed the result obtained in vitro cell tests. The neutrophils stimulated by fine particles may cause the inflammatory cascade and harm the surrounding tissue.

Assessment of the potentialin vivoecotoxicity of Double-Walled Carbon Nanotubes (DWNTs) in water, using the amphibianAmbystoma mexicanum

“…In spite of this economical and technological context, it is surprising that only very few studies have been published about their potential toxicity. The vast majority of the studies focusing on the impact of CNTs has been devoted to the study of the toxicity and immunotoxicity in in vitro cellular models on human or rat cells (Shvedova & Castranova 2003;Tamura et al 2004, see for review Smart et al 2006;Cui et al 2005;Jia et al 2005;Monteiro-Rivière et al 2005;Muller et al 2005;Salvador-Morales et al 2006 Smart et al (2006) indicated that in the last five years, disturbing and often conflicting data have emerged concerning the safety of CNTs. To our knowledge no information is currently available about the toxic effects of such materials in in vivo studies, except the following studies on aquatic organisms: (i) Freshwater crustaceans (Daphnia magna and Hyalella azteca ), a marine copepod and fish (Pimephales promelas and Oryzias latipes ) exposed to C60 (fullerenes) (Oberdö rster 2004a,b;Oberdörster et al 2006), (ii) on zebrafish embryos (Danio rerio ) exposed to SWNTs and DWNTs (Cheng et al 2007), (iii) on estuarine copepod (Amphiascus tenuiremis ) exposed to SWNTs (Templeton et al 2006) and (iv) on juvenile trout (Oncorhynchus mykiss) exposed to SWNTs (Smith et al 2007).…”

Apatite formation on carbon nanotubes

“…The modifications of CNTs have been extensively investigated because of their relevance in electrical, mechanical and biological applications [1][2][3][4][5][6][7][8]. Immobilization of various functional molecules on CNT has also been examined in past studies [9][10][11][12].…”

Comparison of cytotoxic and inflammatory responses of photoluminescent silicon nanoparticles with silicon micron‐sized particles in RAW 264.7 macrophages

“…responses of cells treated with nanoparticles of other materials (Dick et al, 2003;Brown et al, 2004;Tamura et al, 2004;Geiser et al, 2005;Inoue et al, 2006;Lee et al, 2007;Rothen-Rutishauser et al, 2007;Waldman et al, 2007). Inoue et al (2006) studied the effects of two different sized (14 and 56 nm diameter) carbon nanoparticles on murine lung macrophage and found that the smaller (d = 14 nm) carbon nanoparticles induced more IL-2 and IL-10 compared with the larger (d = 56 nm) particles.…”

“…The engulfment and the final intracellular location of the nano-and microparticles may be different, and will lead to diverse biological responses by the macrophages. Localization of nanoparticles inside the cell may ultimately play a role in the biological responses, whether located along the inner or outer membrane surface or outside of the cell membrane (Tamura et al, 2004;Rothen-Rutishauser et al, 2007). Tsoli et al (2005) demonstrated that gold nanoparticles localized in the vicinity of the cell nuclei and interacted with DNA, leading to pronounced toxicity.…”