Researchers Employ Nanocontainers to Combat Cardiovascular Disease

By Will SoutterJun 12 2012

Cardiovascular disease as a result of atherosclerosis is estimated to contribute to 37% of all deaths in Switzerland each year.

Current treatment methods are characterized by side effects as drugs cannot be administered to target just the diseased areas alone. A vasodilator like nitroglycerin that dilates blood vessels is usually administered intravenously. But this dilates the healthy arteries too and causes a drop in blood pressure which in turn limits the blood flow that would be expected from the vasodilatation in the event of a heart attack. Researchers from the University of Geneva and the University of Basel have engineered nanocontainers to administer the vasodilator to the diseased areas alone in order to reduce the side effects.

Atherosclerosis is characterized by the constriction of blood vessels known as shear stress, which acts parallel to the blood flow, and is caused by fluctuation in blood flow. The researchers made use of this physical phenomenon to introduce a nanocontainer containing vasodilator akin to a time bomb into the system which would explode due to the pressure exerted by the shear stress and release the contents only to the diseased arteries. Nanocontainers are usually spherical in shape. But for the purpose of treatment, they are required to be of lenticular shape so that they can travel through healthy arteries without breaking. The researchers achieved the change in shape by modifying the structure of phospholipid molecules in the nanocontainers by replacing the ester bond between two portions of the phospholipid with an interaction promoting amide bond. The modified molecules are made to form a liquid sphere by hydration followed by heating. The sphere cools down into a solid in lens form.