A new nanogel could make for a better snake antivenom, by
sequestering the toxins within the bloodstream(Credit:
SURZet/Depositphotos)
According to the
World Health Organization, snakes bite an estimated 5
million people each year, killing more than 100,000 of those
victims and permanently injuring hundreds of thousands more.
Current antivenoms might not be saving lives as efficiently as
they could be, given that they're difficult and expensive to
produce, distribute and administer. Now, researchers at the
University of California, Irvine (UCI) have developed a
synthetic alternative with a long shelf-life that can neutralize
the venom from several species of snakes.
Although existing antivenom treatments are effective
at preventing death or long-term disability like amputation,
they aren't easy to make, store or ship. One of the most common
ways is to inject a horse or sheep with a non-lethal dose of a
venom, wait for the animal to develop antibodies against the
toxins, and then harvest and process those antibodies into an
antivenom.
That technique is problematic for several reasons.
For one, it's expensive, which means that it isn't accessible in
the poorer rural areas of the world where the majority of snake
bites occur. It also needs to be refrigerated, making storage
and shipping tricky, and most antivenoms are only effective
against bites from a single species of snake. The UCI team says
their synthetic solution could solve all of these issues.
"Current antivenom is very specific to certain snake
types," says Jeffrey O'Brien, lead author of the study. "Ours
seems to show broad-spectrum ability to stop cell destruction
across species on many continents, and that is quite a big deal.
Our treatment costs pennies on the dollar and, unlike the
current one, requires no refrigeration. It feels pretty great to
think this could save lives."
The team's treatment, which they call a "nanodote,"
is built around a specially-designed polymer nanogel. When
injected, nanoparticles in the material absorb the venom by
binding to certain protein toxins that are common to several
species of deadly snakes. These particles sequester and
neutralize the toxins, keeping the poison from attacking red
blood cells and causing the serious haemorrhaging that can
sometimes be fatal.
Since the nanodote ingredients are easy to obtain,
it's much cheaper to produce than the current antidotes, and can
sit unrefrigerated for much longer. That means it could be
shipped at low-cost to remote areas as part of a standard
medical package to treat bites from a variety of snake species.
"The military has platoons in the tropics and
sub-Saharan Africa, and there are a variety of toxic snakes
where they're traipsing around," says Ken Shea, senior author of
the study. "If soldiers are bitten, they don't have a hospital
nearby; they've got a medic with a backpack. They need something
they can use in the field to at least delay the spread of the
venom."
The researchers are preparing for clinical trials
and have applied for patents for their treatment. In future, the
nanodote could also be modified to work on the venom of spiders,
scorpions and bees.