Preliminary technological assessment of microneedles-based dry electrodes for biopotential monitoring in clinical examinations

Monitoring biosignals, such as in electrocardiography (ECG), electromiography (EMG) and electroencephalography (EEG), is important for a better understanding of the pathological and physiological conditions of human subjects. In clinical practice the recording of biopotentials is carried out in general with wet electrodes, considered as the golden standard, although they have shown some limits: (i) the susceptibility to motions artifacts, critical aspect in ECG and EMG monitoring, (ii) the time-consuming procedure to be applied in EEG examinations, and (iii) the inability to record biosignals in long-term applications. In the past years innovative solutions have been suggested, among which microstructured dry electrodes showed very promising features. This study represents a first technological assessment of a novel type of microneedles-based dry electrodes. In this paper it has been proved that these electrodes: (i) seem to allow a better electro-mechanical interface with human skin, (ii) have performance comparable to wet electrodes in recording EEG, EMG and static ECG signals, showing an improvement in the monitoring of ECG signal in dynamic conditions, and (iii) do not need the long-lasting skin preparation as wet electrodes for EEG applications, appearing easy to use and to apply. In conclusion, our microneedles based dry electrodes seem to be a promising alternative to standard wet electrodes for the recording of biosignals in clinical examinations.