Printable Graphene-Sustainable Elastomer-Based Cross Talk Free Sensor for Point of Care Diagnostics

Abstract

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.

Synthesis of gallic acid-grafted epoxidized natural rubber and its role in self-healable flexible temperature sensors

“…The probing of the underlying sensing mechanism of the polymer and the change in conductivity of the polymer nanocomposite on the application of temperature has been studied. Based on previous reports, 1,2 a variable range hopping mechanism was anticipated to contribute towards the sensing behavior of the developed sensing films. To confirm the above mechanism, ln( σ ) was plotted against the T −(1/4) , as shown in Fig.…”

“…In recent years, flexible and stretchable electronic devices have grown exponentially across myriads of applications ranging from automobile industries to the healthcare sector due to their excellent performance attributes and flexibility in form factor. [1][2][3] The rising popularity of this particular field can be illustrated by the increasing number of publications (around 3.5 million this year) and patent filings. The global market size of flexible electronics has grown from 27.3 billion USD to 31.5 billion USD during the financial year 2022-2023 and is anticipated to exceed USD 61 billion by 2030.…”

Bioinspired Fast Room-Temperature Self-Healing, Robust, Adhesive, and AIE Fluorescent Waterborne Polyurethane via Hierarchical Hydrogen Bonds and Use as a Strain Sensor

“…Here, referring to the method reported in the literature, a glass bottle filled with water is used to simulate the human body, and the eutectic gel sensor glued to the bottle wall can effectively detect the change in water temperature (Figure S23). 59…”

Cross-Talk Signal Free Recyclable Thermoplastic Polyurethane/Graphene-Based Strain and Pressure Sensor for Monitoring Human Motions

“…This causes difficulty to predict whether the signal so generated originated from which external impulse and is commonly referred to as the cross-talk of the signals of the sensors. In terms of the filler, graphene, − carbon nanotubes, ,− silver nanowires, − carbon black, − and hybrid nanostructures − are commonly used as the functional sensing component. However, among the different classes of the fillers that are being used for sensing, graphene has gained a great deal of attention as a potentially useful candidate for the development of new-generation electronic devices. , Under strain, the graphene alters its electronic structure, which in turn will cause a significant shift in the resistance of the material. ,, This ability of graphene along with the superior mechanical and electrical properties, carrier mobility, and ultra-translucency paved the way for graphene to be used in high-sensitivity strain sensors. − …”