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. 2023 Apr 13;13(3):495-504.
doi: 10.1007/s13534-023-00279-7. eCollection 2023 Aug.

Soft, adhesive and conductive composite for electroencephalogram signal quality improvement

Jeong E Jin  1 , Seohyeon Kim  1 , Hyeji Yu  1 , Keyong Nam Lee  2 , Young Rag Do  2 , Seung Min Lee  1
Affiliations

Soft, adhesive and conductive composite for electroencephalogram signal quality improvement

Jeong E Jin et al. Biomed Eng Lett. .

Abstract

Since electroencephalogram (EEG) is a very small electrical signal from the brain, it is very vulnerable to external noise or motion artifact, making it difficult to measure. Therefore, despite the excellent convenience of dry electrodes, wet electrodes have been used. To solve this problem, self-adhesive and conductive composites using carbon nanotubes (CNTs) in adhesive polydimethylsiloxane (aPDMS), which can have the advantages of both dry and wet electrodes, have been developed by mixing them uniformly with methyl group-terminated PDMS. The CNT/aPDMS composite has a low Young's modulus, penetrates the skin well, has a high contact area, and excellent adhesion and conductivity, so the signal quality is enhanced. As a result of the EEG measurement test, although it was a dry electrode, results comparable to those of a wet electrode were obtained in terms of impedance and motion noise. It also shows excellent biocompatibility in a human fibroblast cell test and a week-long skin reaction test, so it can measure EEG with high signal quality for a long period of time.

Keywords: Conductive composite; EEG; Motion artifact; Self-adhesive; Signal quality; Young’s modulus.

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Conflict of interest statement

Conflict of interestThe authors have no relevant financial or non-financial interests to disclose.

Figures

Fig. 1
Fig. 1
Schematic of CNT/aPDMS composite fabrication. a Dipping the aggregated CNTs in IPA. b Released CNTs after sonication in IPA. c stabilized CNTs in IPA after continuous sonication. d MEP attached on the CNTs. e Merging in the aPDMS-A solution. f Evaporation of IPA using heat
Fig. 2
Fig. 2
a EEG measurement patch with CNT/aPDMS composite attached behind the left ear. b Bottom view and (c) top view of the patch
Fig. 3
Fig. 3
a Result of FTIR spectroscopy of aPDMS and CNT/aPDMS. b SEM image of the CNT/aPDMS composite
Fig. 4
Fig. 4
a Contact impedance between CNT/aPDMS and metal plate (Zm). b Intrinsic impedance of CNT/aPDMS (Zi). c Contact impedance to the skin of CNT/aPDMS, dry and Ag/AgCl electrodes (Zc)
Fig. 5
Fig. 5
a Adhesion force according to the concentration of CNTs in aPDMS. b Adhesion change after repeated attachment and detachment, surface cleaning every 10 uses. c Young's modulus measurement
Fig. 6
Fig. 6
Skin penetration test using skin replica with CNT/aPDMS, black tape with gel and black metal
Fig. 7
Fig. 7
a FFT of alpha band experiment before (red) and after (blue) eyes closing and (b) its spectrogram. c Beta band power changes in time domain and (d) its spectrogram. e Theta power before (red) and after (blue) stimuli (f) and its spectrogram. g Averaged EEG of N100 test using sound stimuli. h SSVEP result during light stimuli at 13 Hz
Fig. 8
Fig. 8
a Fluorescent images of live/dead test. Green and red means live (green) and dead (red) cells, respectively. b Cell viability test for various CNT/aPDMS eluate. c A site where CNT/aPDMS was attached to the skin for a week
See this image and copyright information in PMC

References

    1. Henry JC. Electroencephalography: basic principles, clinical applications, and related fields. Neurology. 2006;67(11):2092. doi: 10.1212/01.wnl.0000243257.85592.9a. - DOI
    1. Buzsáki G, Anastassiou CA, Koch C. The origin of extracellular fields and currents—EEG, ECoG LFP and spikes. Nat Rev Neurosci. 2012;13(6):407–420. doi: 10.1038/nrn3241. - DOI - PMC - PubMed
    1. Song Y, Zhang J. Automatic recognition of epileptic EEG patterns via extreme learning machine and multiresolution feature extraction. Expert Syst Appl. 2013;40(14):5477–5489. doi: 10.1016/j.eswa.2013.04.025. - DOI
    1. Tagluk ME, Sezgin N. A new approach for estimation of obstructive sleep apnea syndrome. Expert Syst Appl. 2011;38(5):5346–5351. doi: 10.1016/j.eswa.2010.10.022. - DOI
    1. Sabeti M, Katebi S, Boostani R, Price G. A new approach for EEG signal classification of schizophrenic and control participants. Expert Syst Appl. 2011;38(3):2063–2071. doi: 10.1016/j.eswa.2010.07.145. - DOI

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