They are called therapeutic magnetic microcarriers (TMMC) and they are drug delivery agents which have recently been successfully sent through a living rabbit’s bloodstream to a targeted area for successful administration of a drug. We’re in Fantastic Voyage (for those who don’t know the 1966 movie, it was more notable for then bombshell Raquel Welch’s presence than the science used to shrink a submarine filled with scientists to a microscopic size then injected into a dying diplomat’s bloodstream in an attempt to save his life) territory.
Known for being the world’s first researcher to have guided a magnetic sphere through a living artery, Professor Martel is announcing a spectacular new breakthrough in the field of nanomedicine. Using a magnetic resonance imaging (MRI) system, his team successfully guided microcarriers loaded with a dose of anti-cancer drug through the bloodstream of a living rabbit, right up to a targeted area in the liver, where the drug was successfully administered. This is a medical first that will help improve chemoembolization, a current treatment for liver cancer.
The therapeutic magnetic microcarriers (TMMCs) were developed by Pierre Pouponneau, a PhD candidate under the joint direction of Professors Jean-Christophe Leroux and Martel. These tiny drug-delivery agents, made from biodegradable polymer and measuring 50 micrometers in diameter — just under the breadth of a hair — encapsulate a dose of a therapeutic agent (in this case, doxorubicin) as well as magnetic nanoparticles. Essentially tiny magnets, the nanoparticles are what allow the upgraded MRI system to guide the microcarriers through the blood vessels to the targeted organ. During the experiments, the TMMCs injected into the bloodstream were guided through the hepatic artery to the targeted part of the liver where the drug was progressively released.
Martel’s work was last highlighted here in my April 6, 2010 posting. At that time he was working with bacteria which he and his team had guided into assembling into pyramid shapes. The team had also guided these bacteria through the bloodstream of a rat. There’s more about this earlier work with bacteria in a July 28, 2010 article by Monique Roy-Sole on the Innovation Canada website. As you may have guessed from the ‘pyramids’, Martel’s inspiration for that work came from Egypt,
Martel was inspired by the story of the pyramid of Djoser, built by an estimated 5,000 slaves around 2600 BC, and considered to be the earliest large-scale stone structure known to humankind. He decided to employ 5,000 bacteria in a drop of water as mini workers to construct a similar step pyramid in less than 15 minutes.
As for Martel’s first breakthrough (from Sole’s article),
In 2007, he and researchers from École Polytechnique and the Centre Hospitalier de l’Université de Montréal successfully injected a tiny magnetic device, measuring 1.5 millimetres in diameter, into the carotid artery of a pig, controlling and tracking its travels in the bloodstream with a clinical magnetic resonance imaging (MRI) scanner. Since then, Martel and his team have been working at reducing the size of the device so it can circulate in smaller blood vessels. This would allow doctors to diagnose and treat areas of the body that current instruments, such as catheters, cannot reach.
I hope this proves to be successful. As anyone who’s had a family member or friend undergo cancer treatments knows, the procedures and medicines are crude in that they destroy healthy as well as diseased tissue. Hopefully, this kind of work will make the cures less drastic.