Using a modified thermal inkjet
printer technology, researchers have
developed a patch that that painlessly
releases medications through the skin.
Researchers at Hewlett-Packard Company
say they that the patch uses
microneedles to inject drugs just
below a patient’s skin and can be
programmed to control precisely the
amount and timing of each dose that is
delivered.
Microneedles are a new and upcoming
transdermal drug delivery technology,
according to John O’Dea, chief
executive officer of Crospon Limited
in Galway, Ireland, which has licensed
the patch and plans to develop it into
a commercial product.
However, the inkjet technology used in
the patch is not exactly the same as
that used in Hewlett-Packard (HP)
printers.
HP’s inkjet printer technology uses a
superheated vapor explosion, lasting
just two-millionths of a second, to
deliver a drop of ink to a piece of
paper, according to the company’s
website.
The patch employs a modified version
of this technology, using a different
material that expands when heated to
deliver the drug, Lim Eng Hann,
associate director of Intellectual
Property Licensing at HP, said.
While the microneedles penetrate the
skin, the patch is painless to use.
The microneedles, explained Lim Eng
Hann, are designed in such a way that
they do not penetrate the skin deep
enough to impact the nerves.
Nerves are located approximately 700
microns, or millionths of a meter,
below the top layer of skin. But the
microneedles will only penetrate 75
microns to 100 microns, John O’Dea
said.
The microneedle patch, equipped with
basic electronics and a power source,
measures roughly 2.5 centimetres
square and is 3 millimetres thick. The
patch will pack between 400 to 1,000
microneedles and include a power
source, such as a battery, as well as
electronics to control when drugs are
administered and in what quantity.
Despite the electronics, HP’s patch is
broadly similar to a transdermal
nicotine patch used to help people
quit smoking. But, while nicotine can
be
absorbed through the skin, HP’s
microneedles penetrate the skin and
can deliver drugs, such as
biopharmaceuticals, that have
molecules too large to be absorbed
through the skin.
HP’s microneedle patch can also be
used to deliver several different
drugs, and is suited well to
situations where a patient requires
timely delivery of these drugs.
Crospon Limited plans to develop the
patch further and will work with
pharmaceutical companies to bring the
product to market. That process will
take six to nine months, and a
commercial product could be available
in about three years’ time, pending
regulatory approval, John O’Dea said.
Meanwhile, researchers at the
University of California at Berkeley,
the United States, and the
Massachusetts Institute of Technology,
the United States, are also trying to
commercialize new types of injection
systems.
