Distribution of Particles

The body distribution of particles is strongly dependent on their surface characteristics. For example, coating poly(methyl methacrylate) nanoparticles with different types and concentrations of surfactants significantly changes their body distribution. Coating these nanoparticles with ≥ 0.1 % poloxamine 908 reduces their liver concentration significantly (from 75 to 13 % of total amount of particles administrated) 30 min after intravenous injection. Another surfactant, polysorbate 80, was effective above 0.5%. A different report shows that modification of the nanoparticle surface with a cationic compound, didodecyldimethylammonium bromide (DMAB), facilitates the arterial uptake 7–10-fold.

Influence of the surfactant concentration on the body distribution of nanoparticles. Journal of Drug Target 1999, 6:373-385.




A New Cancer Treatment Idea From an Unexpected Source


......Kanzius' contribution is a radio frequency (RF) transmitter of his own design that excites metal nanoparticles inserted into cancer cells. When exposed to radio waves, these nanoparticles generate tiny, localized bursts of heat that kill cancer cells without harming adjacent tissues. The technique has so far been tested only in laboratory experiments with cultured cancer cells and animal models. Moreover, several toxicity and safety issues must still be resolved before the technique can be considered viable for testing in humans. Kanzius and his collaborators acknowledge that human clinical trials are years away.


http://jnci.oxfordjournals.org/cgi/content/full/100/14/985



Ethical analysis


One of the prominent claims made about nanotechnology and Convergence is that our new found capacity to understand and directly manipulate the building blocks of life enables us to control aspects of human evolution that were previously subject to blind chance and natural selection. But this Promethian aspect of the Convergence project is not new. In fact, in the early days of recombinant DNA research, these claims were often advanced by leading scientists. .................As the science developed, and as techniques for reprogenetics were refined, there was a marked shift in the form and character of ethical analysis. In 1991, a Program Officer for the ELSI arm of the Human Genome project, edited an issue of this Journal which was quite influential. In 1991 the views of people like Ramsey was characterised as "romantic." People were struggling to take hold of the genuine ethical issues as they first contemplated the rich possibilities of the emergent science. But this imprecise, proto-scientific discourse was seen giving way to a new stage of precision in ethical analysis, where careful distinctions and a scientific temper dominates (Jonsen, 1998, ch. 6).


Open Questions in the Ethics of Convergence, Routledge, Journal of Medicine and Philosophy, 32:299–310, 2007; Accessed through ox.ac.uk