Performance Assessment of Microneedle Dry and Wet Gel Electrodes Using a Dual-Channel, Single Lead Wearable ECG Device

This paper presents a dual channel, wearable ECG measurement device (7.2 x 3.9 cm(2)) that can simultaneously acquire and record signals from two different sets of electrodes. Intended for the benchmarking of the performance of microneedle-based dry electrodes against that of commercial wet electrodes, the device consists of two MAX86150 ECG analog front-ends and an ESP32 system on chip, which has built in wireless facilities. An I2C serial communication was established for the data transfer from sensor to host and vice-versa. Further, the device was enclosed in a 3-D printed housing for wearability and signal recording purposes. Two female snap fasteners were attached to the rear side of housing and the adhesive part of gel electrodes was used to affix the device onto the chest. ECG signals were measured simultaneously using gel and microneedle-based dry electrodes, and data was transferred via Bluetooth to a laptop where a Labview-based GUI was used for recording and signal analysis. The performance of the electrodes was assessed based on correlation coefficient and kurtosis, estimated for the 16 s of the recorded ECG signal. Microneedle-based dry electrodes and commercial wet electrodes show comparable results in terms of signal characteristics and correlation (r = 0.94). In addition, kurtosis values were more than 5 for the recorded signal from both the electrodes, confirming the usability of the dry electrodes and the robustness of the device.