Affordable Access

Publisher Website

Hydroxyapatite nano and microparticles: Correlation of particle properties with cytotoxicity and biostability

Authors
Journal
Biomaterials
0142-9612
Publisher
Elsevier
Publication Date
Volume
30
Issue
19
Identifiers
DOI: 10.1016/j.biomaterials.2009.02.044
Keywords
  • Hydroxyapatite
  • Nanoparticles
  • Cytotoxicity
  • Slow Release
  • Vaccine Delivery
  • Transfection
Disciplines
  • Chemistry

Abstract

Abstract Synthetic colloid and gel hydroxyapatite (HA) nanoparticles (NPs) were spray dried to form microparticles (MPs). These are intended for use as slow release vaccine vectors. The physico-chemical properties of gel and colloid NPs and MPs were compared to those of HA obtained commercially. Their cytotoxicity to human monocytes'-derived macrophages (HMMs) was assessed in vitro using a range of techniques. These included the MTT assay, LDH leakage and a confocal based live–dead cell assay. Cytotoxicity differed significantly between preparations, with the suspended gel preparation being the most toxic (31–500 μg/ml). Other preparations were also toxic but only at higher concentrations (>250 μg/ml). Transmission electron microscopy (TEM) and stereology showed variable cellular uptake and subsequent dissolution of the various forms of HA. We have demonstrated that HA particle toxicity varied considerably and that it was related to their physico-chemical properties. Cell death correlated strongly with particle load. The intracellular dissolution of particles as a function of time in HMM suggests that increased cytoplasmic calcium load is likely to be the cause of cell death. Some HA NPs eluded the phagocytic pathway and a few were even seen to enter the nuclei through nuclear pores.

There are no comments yet on this publication. Be the first to share your thoughts.