الفهرس 
ElectrophysiologyOnly 14 pages are availabe for public view
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Abstract
Electrophysiological signals are low-level electrical biopotentials that derive and control the activity of most human body movements. Electrocardiograms (ECG) are electrophysiological signals produced due to the electrical activity changes in the human heart. These signals can reflect the real physiological status of the heart, thus are vital for several disease diagnosis and abnormal heart conditions. Flexible wearable electrodes have been extensively used for obtaining electrophysiological signals towards smart health monitoring and disease diagnosis. Natural silk fibroin, a natural biomaterial, has attracted a lot of interest in flexible wearable biosensing applications due to its nature biocompatibility, flexibility, confirmability and unique mechanical strength.
In this thesis, natural, low-cost, and non-conductive silk Fabric (SF) have been processed into highly conductive laser induced graphene (LIG) electrodes with a minimum sheet resistance of 5.5 Ω/sq while maintaining the original structure of SF. A CO2-pulsed laser was utilized to produce LIG-SF with controlled sheet resistance and mechanical properties. Laser processing of SFs under optimized conditions yielded LIG-SF electrodes with a high degree of homogeneity on both, top and bottom layers. Silk fibroin/Ca2+ adhesive layers effectively promoted the adhesive, anti-bacterial properties and provided a conformal contact of LIG-SF electrodes with human skin. Compared with conventional silver/silver chloride (Ag/AgCl) electrodes, adhesive LIG-SF electrodes possesses a much lower contact impedance in contact with human skin enabling highly stable electrophysiological signals recording.
The applicability of adhesive LIG-SF electrodes to acquire ECG signals was investigated in comparison with conventional Ag/AgCl electrodes. ECG signals at different physiological states (Resting, walking, and running) has been investigated. At resting state, both types of electrodes showed a comparable performance. However, ECG recordings of adhesive LIG-electrodes showed an excellent performance compared to conventional Ag/AgCl electrodes at intense body movements while running at different speeds for up to 9 Km. Moreover, while recording ECG signals continuously for 24 h, adhesive LIG-SF electrodes showed a unique performance in comparison to conventional Ag/AgCl electrodes. Our proposed adhesive LIG-SF electrodes can be applied for long-term healthcare monitoring and sports management applications.
To conclude, our proposed silk-based adhesive LIG-SF electrodes pave the way for next-generation sustainable and environment-friendly wearable biosensors