The growing threat posed by antimicrobial resistance on the healthcare and economic well‐being of mankind is pushing the need to develop novel and improved diagnostic platforms for its rapid detection at point of care, facilitating better patient management strategies during antibiotic therapy. In this paper, we present the manufacturing and characterisation of a low‐cost carbon screen‐printed electrochemical sensor on a ceramic substrate. Using label‐free electrochemical impedance spectroscopy, the sensor is demonstrated for the detection of blaNDM, which is one of the main antimicrobial resistance factors in carbapenem‐resistant Enterobacteriaceae. The electrochemical performance of the newly fabricated sensor was initially investigated in relation to the function of its underlying composite materials, evaluating the choice of carbon and dielectric pastes by characterising properties like surface roughness, wetting and susceptibility of unspecific DNA binding. Subsequently, the sensor was used in an electrochemical impedance spectroscopy assay for the sensitive and specific detection of synthetic blaNDM targets achieving a detection limit of 200 nM. The sensor properties and performance demonstrated in this study proved the suitability of the new electrode materials and manufacturing for further point‐of‐care test development as an inexpensive and effective alternative to gold electrodes sensor.

Multi-node leadless pacemaker system overcomes the main limitations related to lead complications of the conventional cardiac pacemaker and will thus replace them in the near future. The multiple nodes of the technology require the development of low-power, low data-rate and energy-efficient communication framework for device synchronization and bi-directional communication between them. Moreover, the nodes need to communicate with the outer peripheral devices for data telemetry, control and remote monitoring. This paper focuses on evaluation of different energy-efficient modulation schemes at 433 MHz for bi-directional communication between the nodes using homogeneous liquid phantom model of human heart and living animal experiments. In this paper, we have analyzed three simple, low-budget modulation schemes-On Off-Keying (OOK), Frequency Shift-Keying (FSK), and Gaussian Frequency Shift-Keying (GFSK). The analysis is done based on the total transmitter power required to achieve a reliable communication indicated by the minimum threshold values of bit-error rate and packet-error rate. The experiments have been conducted for three common implant communication scenarios-in-body to in-body, in-body to on-body and in-body to off-body links. For conducting the experiments, we have designed the experimental setup with electronic components and fabricated antennas. The results have shown that GFSK has the best performance among the other modulation techniques based on the total transmitter power. We also investigated higher order of the same modulation schemes-4-FSK and 4-GFSK. The results showed that GFSK performed much better than 4-FSK and 4-GFSK. This research will be carried forward to build the entire radio frequency communication framework for the multi-node pacemaker technology.

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A new field emission model of carbon nanotubes (CNTs) to simulate gas detection mechanism in CNT based ionization gas sensor has been developed. The new model consists of three modules which are combined together and embedded in the standard particle-in-cell/Monte Carlo collision codes. The functionality of the enhanced model is checked by varying the gas pressure and gap spacing in the simulations. From the results, around one order of magnitude decrease in the breakdown voltages and two orders of magnitude faster response time is observed. The lowest breakdown voltages are observed when intertube spacing is equal to height of the nanotube. The field enhancement factor β is calculated from our model and compared with the β of the well established model. The closeness among the values of β validates the performance of our field emission model. Furthermore, the β of our model is compared with the β of the existing ionization gas sensors. It was found that the β of our sensor is around 3 times better than the β of the gold nanowire based ionization gas sensor and 28 times better than the β of the other CNT based ionization gas sensor. These results suggest that by properly controlling the growth of CNT structures, an optimized CNT based ionization gas sensor can be realized.

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