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

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.

Printable Carbon Nanotube-Liquid Elastomer-Based Multifunctional Adhesive Sensors for Monitoring Physiological Parameters.

Developing a printed elastomeric wearable sensor with good conformity and proper adhesion to skin, coupled with the capability of monitoring various physiological parameters, is very crucial for the development of point-of-care sensing devices with high precision and sensitivity. While there have been previous reports on the fabrication of elastomeric multifunctional sensors, research on the printable elastomeric multifunctional adhesive sensor is not very well explored. Herein, we report the development of a stencil printable multifunctional adhesive sensor fabricated in a solvent-free condition, which demonstrated the capability of having good contact with skin and its ability to function as a temperature and strain sensor. Functionalized liquid isoprene rubber was selected as the matrix while carboxylated multiwalled carbon nanotubes (c-CNTs) were used as the nanofiller. The selection of the above model compounds facilitated the printability and also helped the same composition to demonstrate stretchability and adhesiveness. A realistic three-dimensional microstructure (representative volume element model) was generated through a computational framework for the current c-CNT-liquid elastomer. Further computational simulations were performed to test and validate the correlation between electrical responses to that of experimental studies. Various physiological parameters like motion sensing, pulse, respiratory rate, and phonetics detection were detected by leveraging the electrically resistive nature of the sensor. This development route can be extended toward developing different innovative adhesives for point-of-care sensing applications.

Patterns and Trends of Tribal Leprosy: An Overview from a Tertiary Care Leprosy Clinic of Choto Nagpur Plateau of Eastern India.

Background: Leprosy is a chronic granulomatous disease mainly affecting the peripheral nerves and skin. Any communities including the tribals are susceptible to leprosy. Very few studies on clinico-epidemiological patterns of leprosy have been reported in the tribal population, especially in the Choto Nagpur plateau. Aims: To observe clinical types of newly diagnosed leprosy cases among the tribal population and demonstrate bacteriological index, frequency of deformity, and lepra reaction at presentation. Methods: An institution-based cross-sectional study was conducted with consecutive newly diagnosed tribal leprosy patients attending the leprosy clinic of a tribal-based tertiary care center of Choto Nagpur plateau of eastern India, from January 2015 to December 2019. Thorough history taking and clinical examination were done. A slit skin smear for AFB was performed to demonstrate the bacteriological index. Results: There was a steady rise in total leprosy cases from 2015 to 2019. Borderline tuberculoid (BT) was the commonest form of leprosy (64.83%). Pure neuritic leprosy was not uncommon (16.26%). Multibacillary leprosy was noted in 74.72% of cases and childhood leprosy was observed in 6.70% of cases. The commonest nerve involved was the ulnar nerve. Garde II deformity was noted in around 20% of cases. AFB positivity was observed in 13.73% of cases. A high bacteriological index (BI ≥3) was noted in 10.65% of cases. Lepra reaction was observed in 25.38% of cases. Conclusion: BT leprosy, pure neuritic leprosy, childhood leprosy, grade II deformity, and higher AFB positivity were prevalent in this study. The tribal population required special attention and care for the prevention of leprosy amongst them.