Sperm cells containing magnetic nanoparticles can still fertilize eggs
The low toxicity and magnetic properties of iron oxide nanoparticles have led to their use in various biomedical and diagnostic applications such as cell labelling and targeting, drug delivery and tissue repair. However, their affect on sperm cells has never been investigated. Researchers at the Bar-Illan University in Israel now show that loading sperm cells with magnetic nanoparticles does not affect the way they move or their ability to fertilize an egg.
Aharon Gedanken and co-workers1 incubated polyvinyl alcohol-coated iron oxide nanoparticles with bovine sperm cells for different periods of time. This coating, which protected the nanoparticles from oxidation, improved the particle uptake by the cells. Nearly half of the nanoparticles that entered the sperm were bound to various parts of the cell, with the highest density seen in the mitochondria, where energy is generated.
Nanoparticle-treated sperm was able to fertilize eggs with the same success rate as untreated sperm. Consequently, the presence of iron nanoparticles has no effect on the sperm’s motility or its ability to undergo the acrosome reaction — the process in which it fuses with an egg. In the future, magnetic nanoparticles could be used to transport drugs into sperm cells.
Makhluf, S. B.-D., Qasem, R., Rubinstein, S., Gedanken, A. & Breitbart, H. Langmuir (2006). 10.1021/la061988z