Medical Design Briefs - September 2022 - 25

n Breath-Driven Concept
Could Transform
Prosthetics
Researchers have developed a new
breath-driven concept set to transform
access to hand prosthetics.
(Credit: University of Oxford)
Researchers have developed
a hand prosthesis powered
and controlled by the
user's breathing. The simple,
lightweight device offers
an alternative to Bowden
cable-driven body-powered
prosthetics initially developed
in the early 19th century - particularly for those too
young or anatomically unsuited to an uncomfortable harness
and cable system.
The new approach provides an alternative body-powered
device for users in situations where cost, maintenance, comfort,
and ease of use are primary considerations. By regulating
their breathing, users power a small purpose-built Tesla
turbine that can accurately control the prosthetic finger
movements. The volume of air needed to power the unit can
be achieved by young children, and the gearing in the unit
determines the speed of the grasping action.
Cable and harness free, the device is suitable for children
and adolescents who are still growing. Minimal maintenance
and training are needed for ease of use in comparison to
other prosthetic options.
For more information, visit www.medicaldesignbriefs.com/
roundup/0922/prosthetics.
n Copper Nanowires
Combat Spread of
Diseases
An ancient metal used
Left: Scanning electron microscopy image
of the network on a copper-sprayed
surface. Right: Up-close image of nanowire.
(Credit: Ames National Laboratory)
for its microbial properties
is the basis for a
materials- based solution
to disinfection. A
team of scientists has
developed an antimicrobial
spray
that
deposits
a layer of copper
nanowires onto high-touch surfaces in public spaces.
The spray contains copper nanowires (CuNWs) or copperzinc
nanowires (CuZnNWs) and can form an antimicrobial
coating on a variety of surfaces. This research was initiated
by the COVID-19 pandemic, but the findings have wider-reaching
applications.
First the surface needs to be cleaned and disinfected,
then the reformulated copper ink solution can be applied.
The ideal coating should be thin enough to be transparent.
The ink can be diluted with water or alcohol to make it
sprayable, and it works on plastic, glass, and stainless-steel
surfaces.
The team tested two types of copper ink: CuNW and CuZnNW.
Compared to a plain copper disk, both inks were just as
effective at disabling the virus. The nanowires worked faster
because of their greater surface area.
For more information, visit www.medicaldesignbriefs.com/
roundup/0922/nanowires.
Medical Design Briefs, September 2022
Electrospun nanofibers boast
numerous advantages over
conventional bulk materials
for the development of
wearables. (Credit: Sameer
Sonkusale)
Participants rode on stationary
bikes to produce enough sweat
for the study's sensor to analyze.
(Credit: Getty Images)
n 'Smart' Necklace May
Track Health Through Sweat
A team of researchers has
demonstrated a battery-free, wireless
biochemical sensor that detected
the blood sugar - or glucose
- humans excrete from their skin
when they exercise.
The team fabricated a smart
necklace - complete with a
functional clasp and pendant -
which, once placed around their
necks, was used to monitor the glucose level of study participants
as they exercised.
Instead of a battery, it works using a resonance circuit, which
reflects radiofrequency signals sent out by an external reader system.
After engaging in indoor cycling for 30 minutes, participants
took a 15-minute break, during which they drank sugar-sweetened
beverages, before resuming cycling.
The results showed the sensor tracked the glucose levels successfully,
which suggests it will work to monitor other important
chemicals in sweat. Additionally, the smart necklace requires only
a minimum amount of sweat for the interface to work due to the
miniaturized structure of the sensing interface.
For more information, visit www.medicaldesignbriefs.com/
roundup/0922/necklace.
n Electrospinning Advantages
for Wearable Technology
Researchers have shown that
electrospun materials have many
advantages over conventional bulk
materials for the development of
wearables. Electrospun materials'
high surface-to-volume ratio endows
them with enhanced porosity and
breathability, which is important for
long-term wearability. Also, with the
appropriate blend of polymers, they
can achieve superior biocompatibility.
Conductive electrospun nanofibers
provide high surface area electrodes, enabling both flexibility and
performance improvements, including rapid charging and high
energy storage capacities. Also, their nanoscale features mean
they adhere well to the skin without need for chemical adhesives.
Electrospinning is considerably less expensive and more userfriendly
than photolithography for realizing nanoscale transistor
morphologies with superior electronic transport. The researchers
are confident that electrospinning will further establish its claim
as a versatile, feasible, and inexpensive technique for the fabrication
of wearable devices in the coming years.
They note that there are areas for improvement to be considered,
including broadening the choice for materials and improving
the ease of integration with human physiology. They suggest
the aesthetics of wearables may be improved by making them
smaller and, perhaps, with the incorporation of transparent materials,
almost invisible.
For more information, visit www.medicaldesignbriefs.com/
roundup/0922/wearables.
www.medicaldesignbriefs.com
25
http://www.medicaldesignbriefs.com/roundup/0922/necklace http://www.medicaldesignbriefs.com/roundup/0922/prosthetics http://www.medicaldesignbriefs.com/roundup/0922/nanowires http://www.medicaldesignbriefs.com/roundup/0922/wearables http://www.medicaldesignbriefs.com
Medical Design Briefs - September 2022

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