Shaped Nanoparticles Target Narrowed Blood Vessels

A clever way to target an infused therapy to particular regions in the body by using their physical properties: "Treatment options [for atherosclerosis] are currently available to people who suffer from the disease but no drug can target solely the diseased areas, often leading to generalized side effects. Intravenous injection of a vasodilator (a substance that dilates blood vessels), such as nitroglycerin, dilates both the diseased vessels and the rest of our arteries. Blood pressure can thus drop, which would limit the desired increased blood flow generated by vasodilatation of diseased vessels and needed for example during a heart attack. In order to increase the effectiveness of treatments against atherosclerosis and to reduce side effects, a team of researchers [have] developed nanocontainers having the ability to release their vasodilator content exclusively to diseased areas. ... Though no biomarker specific to atherosclerosis has been identified, there is a physical phenomenon inherent to stenosis (the narrowing of blood vessels) known as shear stress. This force results from fluctuations in blood flow induced by the narrowing of the artery and runs parallel to the flow of blood. It is by making use of this phenomenon that the team of researchers has developed a veritable 'time bomb', a nanocontainer which, under pressure from the shear stress in stenosed arteries, will release its vasodilator contents. By rearranging the structure of certain molecules (phospholipids) in classic nanocontainers such as liposome, scientists were able to give them a lenticular shape as opposed to the normal spherical shape. In the form of a lens, the nanocontainer then moves through the healthy arteries without breaking. This new nanocontainer is perfectly stable, except when subjected to the shear stress of stenosed arteries."

Link: http://www.eurekalert.org/pub_releases/2012-06/udg-rda060812.php