Nanoparticle engineering opens up avenues for delivering medicines to the right place in the body, and it could spell radical new treatments for previously incurable diseases. Claire O'Connellreports
The next big thing in medicine is going to be small. Very small. Tiny, smart drugs that can wriggle into previously inaccessible parts of the body to work right where they are needed and even markers that highlight a single cancer cell in the body are all on the horizon thanks to the emerging field of nanomedicine.
The approach harnesses the power of "nanoparticles", particles only a few billionths of a metre across, that can be tailored to access hard-to-reach areas of the body like the brain or the interiors of individual cells.
It opens up avenues for delivering medicines to the right place in the body, and it could spell radical new treatments for previously incurable diseases, explains chemist Prof Kenneth Dawson, who heads the new nanobiology and nanomedicine centre at University College Dublin (UCD).
Thanks to their size, nanoparticles can be engineered to get to hard-to-reach areas in the body where disease lurks. "You can't really get at where viruses live, which is inside the cell. They tend to be inaccessible," explains Dawson. "It's also difficult to treat diseases of the brain, like neurodegenerative diseases, because it's hard to get anything through there."
But a nanoparticle-based drug-delivery system can be tagged with a molecular "swipe card" to cross into the brain, or to zone in on a particular compartment within a cell, he adds. "Normally to get them into these places you have targeting machinery on them, and I think the biggest and most important new area in medical science is understanding how to target those places," says Dawson.
And while the research is currently mostly in the lab, he foresees enormous clinical impact, particularly for attacking elusive agents of disease like viruses that hide away deep inside cells. "Nanomedicine could really be the only means to cure some diseases. The portals to get into some of those places are so small that unless you go to that size you are not getting in. Old-style delivery could deliver to organs but this is getting to the nub of it, getting inside cells and inside the brain."
Zoning in on specific parts of the body also means that nanodrugs can work more efficiently and have fewer side effects, says Marek Radomski, professor of pharmacology at Trinity College Dublin, who forecasts "significant developments" in nanodrugs against cancer in the next few years.
And nanotechnology will also boost early diagnosis - we are moving towards specialised nanoparticles that can be administered to the patient and then provide an image of where a disease is in their body, he adds.
"The big area which is becoming hotter every day is diagnostics, to use nanoparticles to diagnose, particularly for the very early diagnosis of cancer - hopefully being able to pinpoint a single cancer cell well before the cell will grow to a tumour and create problems," he says.
"It gives you amazing resolution. It's mindbending when you think about what can be done."
However, nanomedicine is a new field and the researchers are keen to stress the importance of safety testing. The new attributes that make engineered nanoparticles attractive as therapeutics also raise issues about potential adverse effects on the body.
"Once we discover a nanoparticle has a biological action it's easy to imagine it will be beneficial. But the other side of the coin is to show its toxicological effects," says Radomski, whose research at TCD's Centre on Adaptive Nanostructures and Nanode vices (CRANN) looks at how nanoparticles interact with the body.
"Some nanoparticles will be biocompatible and not others. Why one type is and another isn't we are still not certain and we need to understand why that is."
Dawson echoes the need for vigilance. "When you dig into it, no clear hazard has emerged. Nevertheless it is a new field and all new technologies have to be evaluated - you have got to do due dil- igence and make sure you are not introducing new issues," he says. "It's clear that this is going to change things, and that's really exciting. It's genuinely new with so much exciting opportunity.
"It's vast, it really is a new world."
Prof Marek Radomski and Dr Iona Pratt will address the conference Nanotechnology: implications for human health, the environment and food safety at the Carlton Dublin Airport Hotel on Friday. Log onto nanotech.dit. ie/events/ist07. html