packs, you really need to have a nurse there all
the time,” he explains.
AN IDEA IS BORN
A medical paper about how phase-change
materials, or PCMs, had been tested
on piglets for body cooling provided a
moment of inspiration for Thomas. PCMs
are specialty materials that use chemical
bonds to store and release heat at specific
temperatures. Heat transfer occurs at the
compound’s individual melting and freezing
points—the temperature at which the material changes between solid and liquid phases.
By creating designer compounds that change
phase at an intended temperature, manufactures of these materials are able tailor
refrigerants that are more effective and long
lasting than ice.
Phase-change materials of all types—ice
included—are highly effective at maintaining
temperatures close to their melting points.
For example, ice placed in a four-degree
Celsius refrigerator will take much longer to
melt than ice sitting on a 22-degree counter
top or placed in someone’s 37-degree hand—
or next to a 37-degree baby. Thus, if the
goal for hypothermic treatment is to bring
a baby’s body temperature to 33. 5 degrees,
then a material with a melting point just
below that temperature would be far more
effective than ice.
“The heat transfer from the phase-change
material will stop after the baby and the
material reach the same temperature,”
Thomas explains. “It will melt slowly so you
won’t have to keep changing ice packs.” That
was the idea tested on the piglets, at any rate.
For the babies being treated in his department at Christian Medical College, Thomas
imagined that PCMs could be used in a device
that would maintain an infant’s body temperature at a steady 33. 5 degrees for 72 hours
without costly and complicated electronics or
Twenty-two hundred kilometers away
in a suburb of Delhi, Pluss Advanced
Technologies was engineering custom
phase-change materials for refrigeration
and other industry-specific purposes.
Thomas found the company in a Google
search and got in touch. “I asked them, ‘Do
you have a product that melts at around 32
to 33 degrees?’” he recalls.
“He wrote that he needed three kilograms
of a 32-degree material and gave us some
dimensions,” recounts Pluss’ spokesman,
Ankit Jhanwar. Thomas was looking for just
enough of the material to test his hypothesis,
but for Pluss, it was an unusual request.
“We really don’t supply in kilograms. We
supply in tons,” Jhanwar notes, but adds that
his team was intrigued and agreed to fulfill
Thomas set to work building a prototype
for his idea: a phase-change material cooling
bed for the neonatal intensive care unit. His
goal was to come up with a solution that was
as reliable and easy to use as more expensive
systems, but at price low-resource hospitals
The first results were disappointing: simply
put, the babies’ body temperatures did not
come down. Lack of insulation in the bed
design eventually proved to be the problem.
Heat from the baby’s surroundings rather
than its body was being transferred to the
material, but it took Thomas two years to
identify that as the issue, he admits.
Once the bed was redesigned using a better
insulating material, his team began seeing
the results they sought. They successfully
tested the device on nine asphyxiated babies
in the unit, and in December 2012, Thomas’
invention was recognized for its results
with an innovation award from the National
Neonatology Forum of India.
FROM CONCEP T TO PRODUC T
Despite what appeared to be a scientific
success, Thomas was unsatisfied. He had
found a solution to a prevalent problem, but
felt he had limited capacity to ensure that the
solution reached the people who needed it.
To take the research forward, Thomas
approached Pluss for a second time. He
proposed that they use his prototype to
build a commercial product that they could
sell. He asked for no financial compensation
and was willing to waive any intellectual
Although Pluss had no experience in the
medical devices domain, the team was enthusiastic. “We are not a medical device company.
We had no idea we could do something like
this with this material. But the prospect of
partnering with Thomas to create a product
that had a social impact was exciting,”
Pluss’ engineers were able to develop an
inexpensive and improved model that was
ready for testing within a few months. One
of the key changes they made was switching
from a 33-degree material to a 29-degree
material, which would help cool a baby’s body
temperature more quickly. This was one of the
limitations Thomas had struggled to resolve
with his model.
Pluss makes its phase-change materials
by creating unique mixtures of salts, which
are inorganic, and fatty acids, which are
organic. By experimenting with different
ratios, the team can customize a material’s
melting point to an intended application.
The materials company also customizes the
thermal conductivity for each of its PCM
designs, which affects the rate at which
heat is exchanged. The entire mixture is then
encapsulated in a “polymer matrix” so that
even in a liquid state, the material will not
leak if punctured.
“When it is frozen, it will feel like a rock, and
The company took a
when it has melted, it just feels like a soft solid.
It’s much easier to work with,” Jhanwar explains.
complete leap of faith—
testing and approving
new medical products is
murky and challenging for
newcomers to navigate.