Developing sensors for monitoring physiological parameters
such
as temperature and strain for point of care (POC) diagnostics is critical
for better care of the patients. Various commercial sensors are available
to get the job done; however, challenges like the structural rigidity
of such sensors confine their usage. As an alternative, flexible sensors
have been looked upon recently. In most cases, flexible sensors cannot
discriminate the signals from different stimuli. While there have
been reports on the printable sensors providing cross-talk-free solutions,
research related to developing sensors from a sustainable source providing
discriminability between signals is not well-explored. Herein, we
report the development of a stencil printable composition made of
graphene and epoxidized natural rubber. The stencil printability index
was vetted using rheological studies. Post usage, the developed sensor
was dissolved in an organic solvent at room temperature. This, along
with the choice of a sustainable elastomer, warrants the minimization
of electronic waste and carbon footprint. The developed material demonstrated
good conformability with the skin and could perceive and decouple
the signals from temperature and strain without inducing any crosstalks.
Using a representative volume element model, a comparison between
experimental findings and computation studies was made. The developed
sensors demonstrated gauge factors of −506 and 407 in the bending
strain regimes of 0–0.04% and 0.04%–0.09%, respectively,
while the temperature sensitivity was noted to be −0.96%/°C.
The printed sensors demonstrated a multifunctional sensing behavior
for monitoring various active physiological parameters ranging from
temperature, strain, pulse, and breathing to auditory responses. Using
a Bluetooth module, various parameters like temperature and strain
could be monitored seamlessly in a smart-phone. The current development
would be crucial to open new avenues to fabricate crosstalk-free
sensors from sustainable sources for POC diagnostics.