Observations placeholder
Nanoparticles and cell death
Identifier
006400
Type of Spiritual Experience
None
Background
Our bodies use phosphates too
" phosphates are most commonly found in the form of adenosine phosphates, (AMP, ADP and ATP) and in DNA and RNA and can be released by the hydrolysis of ATP or ADP. ..... Phosphoanhydride bonds in ADP and ATP, or other nucleoside diphosphates and triphosphates, contain high amounts of energy which give them their vital role in all living organisms. They are generally referred to as high energy phosphate, as are the phosphagens in muscle tissue."
A description of the experience
Toxicol Lett. 2013 Dec 18. pii: S0378-4274(13)01461-6. doi: 10.1016/j.toxlet.2013.12.005. [Epub ahead of print] Phosphate-enhanced cytotoxicity of zinc oxide nanoparticles and agglomerates. Everett WN1, Chern C2, Sun D3, McMahon RE2, Zhang X3, Chen WJ4, Hahn MS5, Sue HJ6. Texas A&M University, College Station, TX 77843, United States.
Zinc oxide (ZnO) nanoparticles (NPs) have been found to readily react with phosphate ions to form zinc phosphate (Zn3(PO4)2) crystallites.
Because phosphates are ubiquitous in physiological fluids as well as waste water streams, it is important to examine the potential effects that the formation of Zn3(PO4)2 crystallites may have on cell viability. Thus, the cytotoxic response of NIH/3T3 fibroblast cells was assessed following 24h of exposure to ZnO NPs suspended in media with and without the standard phosphate salt supplement.
Both particle dosage and size have been shown to impact the cytotoxic effects of ZnO NPs, so doses ranging from 5 to 50μg/mL were examined and agglomerate size effects were investigated by using the bioinert amphiphilic polymer polyvinylpyrrolidone (PVP) to generate water-soluble ZnO ranging from individually dispersed 4nm NPs up to micron-sized agglomerates.
Cell metabolic activity measures indicated that the presence of phosphate in the suspension media led to significantly reduced cell viability at all agglomerate sizes and at lower ZnO dosages. In addition, a reduction in cell viability was observed when agglomerate size was decreased, but only in the phosphate-containing media.
These metabolic activity results were reflected in separate measures of cell death via the lactate dehydrogenase assay. Our results suggest that, while higher doses of water-soluble ZnO NPs are cytotoxic, the presence of phosphates in the surrounding fluid can lead to significantly elevated levels of cell death at lower ZnO NP doses.
Moreover, the extent of this death can potentially be modulated or offset by tuning the agglomerate size. These findings underscore the importance of understanding how nanoscale materials can interact with the components of surrounding fluids so that potential adverse effects of such interactions can be controlled.
Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.
PMID: 24362007