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Huang et al. Soft Sci 2024;4:40 https://dx.doi.org/10.20517/ss.2024.37 Page 17 of 35

Table 2. Summary of representative physiological monitoring devices in the past five years with materials, preparation methods,
products and monitoring location
Monitoring
Signals Materials/components Fabrication Products SEI SNR/sensitivity Ref.
location
ECG Ag-plated fibers Electrostatic T-shirt Chest A few hundred k / [213]
flocking Ω at 100 Hz and
1,000 Pa
ECG Ag/M-PETF Electroless T-shirt Chest / / [214]
deposition
ECG Ag/AgCl Screen printing Polyester fabric Hand and leg A few hundred Ω / [215]
within 100 Hz
ECG/EMG rGO, sericin, water retention Knitting Sports RA, RL, LL 24 kΩ at 1,000 35-40 dB at [216]
polymer undergarment, Hz pH = 4.3
sleeve
ECG Fabink-TC-C4001, MOS Screen printing Mattress Back ~200 kΩ at -40 dB [217]
TitanRF 10Hz; 50 kΩ at
100-1,000 Hz
EMG Graphene Dip-coating Sleeve Arms and ~90 kΩ at 1-5 Hz 19.23 dB [218]
legs
EMG PEDOT:PSS Screen printing Sleeve Legs 3-20 kΩ at / [219]
30 Hz
EEG Ag flakes/SIS Screen printing Headband Forehead < 10 kΩ -32.7 dB [220]
EEG Ag Knitting Cap Head 5-30 kΩ at 33.6 dB [221]
0.1-30 Hz
EOG Graphene Dip-coating Headband Forehead / / [183]
ECG/EOG LIG, AgCl, carbon inks Screen printing Fabric Forehead ~700 Ω at / [222]
0.1-500 Hz
EEG/EOG Ag Knitting Headband Forehead / / [223]
Temperature Polycarbonate, battery, Thermal Digital fiber, Body / / [224]
thermistors drawing T-shirt
Temperature PEDOT:PSS, PU/graphene Wet spinning, Fabric Arm / -1.72%/°C [225]
weaving
Temperature Thermal-sensitive ink PDMS Etching, Fabric Lower limb / 62.3 V/K [226]
coating
Respiratory Functional yarns Wrapping Mask Face / 82.4 pF/% RH [227]
Rate
Respiratory Ag NPs Drop casting Chest strap Chest / 0.043 [228]
Rate
SEI: Skin-electrode impedance; SNR: signal-to-noise ratio; ECG: electrocardiograms; M-PETF: modified polyester fabric; EMG: electromyography;
rGO: reduced graphene oxide; RA: right arm; RL: right leg; LL: left leg; Fabink-TC-C4001: silver conductive polymer ink; MOS TitanRF: self-
adhesive conductive textile fabric; PEDOT:PSS: poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate); EEG: electroencephalographic; SIS:
styrene-isoprene-styrene; EOG: electrooculogram; LIG: laser induced graphene; PU: polyurethane; PDMS: polydimethylsiloxane; RH: relative
humidity; NPs: nano-particles.

textile electrodes found that the moss stitch method produced a lower skin-electrode impedance (SEI) than
the lock stitch method. SEI, or the resistance at the skin-electrode interface, is crucial for efficient signal
transmission and high accuracy, which is mainly reflected in the signal-to-noise ratio (SNR). Thus, the moss
stitch method enhances reliable EMG signal acquisition.

Electroencephalographic (EEG) signals capture the electrical activity of the brain, playing a crucial role in
the diagnosis of neurological disorders such as epilepsy, sleep disorders, and brain injury. Tseghai et al.
developed washable and flexible textile electrodes for detecting EEG signals emanating from cerebral
activity . The textile electrodes demonstrate lower SEI compared to conventional Ag/AgCl dry electrodes
[231]
after three minutes [Figure 7E] due to sweat permeating the textile, rendering them highly suitable for long-
term EEG monitoring applications. In Figure 7F, three textile electrodes and two reference electrodes are