All organic graphene oxide and Poly (3, 4-ethylene dioxythiophene) - Poly (styrene sulfonate) coated knitted textile fabrics for wearable electrocardiography (ECG) monitoring

*LH = Left Hand, RH = Right Hand, LL = Left Leg. [Display omitted] •One bath dyeing and reduction of Graphene Oxide was accomplished using the exhaust dyeing method.•The rGO and conductive polymer coated knitted fabric showed better stability against several washing and bending cycles.•The electrode showed improved electrical conductivity with low impedance and used as ECG electrode. This research approach has been used to enhance and investigate the electrical performance of graphene-based textiles by using an exhaust dyeing method. We developed a highly flexible and wearable e-textile for smart clothing in general and electrocardiogram (ECG) biomedical applications in particular. One step dyeing and reduction of graphene oxide on the textile substrate was accomplished simultaneously at 90 °C in 2 h. After one bath dyeing and reduction of GO, the knitted fabric was coated with conductive polymer PEDOT: PSS via dip coating as a layer by layer (LBL) technique. The resultant knitted textile electrode showed a reduction in sheet resistance from 2.5 MΩ∼140KΩ with increasing (1∼10) dyeing cycles. The electrical conductivity was further the improved, as sheet resistance was decreased from 180KΩ∼120Ω when coated with PEDOT: PSS as compared to pristine PEDOT: PSS and rGO. The results showed that washing has an adverse effect on electrical conductivity. The textile electrode was stable up to 20∼30 washing and 120∼130 bending cycles. The developed electrodes were used as an ECG electrode, with low impedance and higher contact to human skin. The textile electrode showed the enhanced performance to detect the high-quality electrocardiograms (ECG) signals for heart rate in both wet and dry conditions.