Houstin Methodist researchers discovered that injecting magnetic nanoparticles with drugs can destroy blood clots 100 to 1,000 times faster than a commonly used clot-busting technique.
The finding, reported in Advanced Functional Materials (early online), is based on experiments in human blood and mouse clotting models. If the drug delivery system performs similarly well in planned human clinical trials, it could mean a major step forward in the prevention of strokes, heart attacks, pulmonary embolisms, and other dire circumstances where clots -- if not quickly busted -- can cause severe tissue damage and death.
"We have designed the nanoparticles so that they trap themselves at the site of the clot, which means they can quickly deliver a burst of the commonly used clot-busting drug tPA where it is most needed," said Paolo Decuzzi, Ph.D., the study's co-principal investigator.
Decuzzi and his team coated iron oxide nanoparticles in albumin, a protein found naturally in blood. The albumin provides a type of camouflage, giving the loaded nanoparticles time to reach their blood clot target before the body's immune system recognizes the nanoparticles as invaders and attacks them. As for the core, iron oxide was used because the researchers plan to use them for magnetic resonance imaging, remote guidance with external magnetic fields, and for further accelerating clot dissolution with localized magnetic heating.
The clot-busting drug loaded into the nanoparticles is tPA is also found naturally in blood at low concentrations. Normally, a hint of tPA is injected into a stroke patient's blood upstream of a confirmed or suspected clot. From there, some of the tPA reaches the clot, but much of it may cruise past or around the clot, potentially ending up anywhere in the circulatory system. tPA is typically used in emergency scenarios by health care staff, but it can be dangerous to patients who are prone to hemorrhage.