A new technology called Nanopatch is showing promise as a needle-free way to deliver vaccines. The technology is the brainchild of biomedical engineer Mark Kendall, who presented it at TEDGlobal 2013 in Edinburgh, Scotland, the birthplace of the needle and syringe in 1853.
Kendall, a professor in the University of Queensland’s Australian Institute for Bioengineering and Nanotechnology, says while the needle and syringe has transformed human fate by preventing disease and extending lifespan, it is 170-year-old technology with a number of limitations that the Nanopatch can overcome.
Unlike the Nanopatch which is coated with dry vaccine, the needle and syringe form of delivery uses liquid vaccine that has to be refrigerated from point of creation, through transport and site storage, to delivery, something referred to as the “cold-chain”. This is very difficult to achieve in poor, remote regions with little or no healthcare infrastructures.
For instance, according to the World Health Organization (WHO), half the vaccines used in Africa aren’t effective because of broken cold chains.
Another disadvantage of needles is the poor immune response because they have to be inserted into muscle, where there aren’t many immune cells. In contrast, the Nanopatch makes thousands of small projections into the skin where immune cells abound.
The Nanopatch is smaller than a postage stamp. It is a one-centimetre-square of silicon, the surface of which has around 20,000 microprojections, all invisible to the naked eye.
Another potential cost saving is that the patch requires less vaccine. Kendall’s studies with animals show that a 450 ng dose of flu vaccine delivered by Nanopatch is more effective than a 600 ng dose delivered via needle.
If such cost reductions turn out to be achievable, the Nanopatch could make it more viable to distribute vaccine, especially the more expensive ones, to the developed world.
And then there is the obvious attraction that being needle-free, a patch is painless, and does not run the risk of needle-stick injuries, which cause around 1.3 million early deaths per year.
At TEDGlobal Kendall announced that a pilot trial for the Nanopatch is about to start in Papua New Guinea, a country with the highest rate of human papillomavirus (HPV) and one of the highest rates of cervical cancer in the world. But, despite having a population of 7 million and being about the same size as France, there are only has 800 fridges for keeping vaccine cold in the whole country.
In a study published in September 2012, researchers in South Korea describe how painless microject injections powered by laser could replace needle jabs for delivering annual flu vaccines.
And in a more a recent study, researchers in the US reported testing a new type of flu vaccine based on the protein ferritin which can self-assemble into nanoparticles.
Mark Kendall, inventor of the Nanopatch, describes the new technology
Written by Catharine Paddock PhD