TY - JOUR
T1 - Temporary Tattoo pH Sensor with pH-Responsive Hydrogel via Initiated Chemical Vapor Deposition
AU - Unger, Katrin
AU - Greco, Francesco
AU - Coclite, Anna Maria
N1 - Funding Information:
The project has received funding from the Women in Science fellowship by L'Oréal and the UNESCO.
Publisher Copyright:
© 2021 The Authors. Advanced Materials Technologies published by Wiley-VCH GmbH
PY - 2022/5
Y1 - 2022/5
N2 - In the expanding field of physiological pH skin sensors, thin temporary tattoo-based devices have gained attention because of ultra-conformal adhesion while providing excellent water vapor transmission. Here, a pH sensor tattoo made of temporary tattoo paper, screen-printed poly(3,4-ethylenedioxythiophene):polystyrene sulfonate electrodes, and pH-responsive hydrogel deposited via initiated chemical vapor deposition, is proposed. The tattoo sensor is easily transferred on skin, maintaining full functionality, and shows excellent conformability to topographical features of epidermis. The investigation of the morphology of all layers within the sensor verifies full control of the desired width of electrodes, thickness of hydrogel, and deposition shielded areas. The hydrogel layer exhibits a reversible pH-responsive swelling of 24.7 ± 0.3% to 38 ± 1%, with respect to the dry state, at pH 4 to pH 6, respectively. Impedance spectroscopy identifies the phase shift at 10 and 1000 Hz as an excellent pH-related property of the sensor, which can be only ascribed to the presence of the hydrogel. The sensors ability to be operated with non-sophisticated read-out hardware and software is also demonstrated.
AB - In the expanding field of physiological pH skin sensors, thin temporary tattoo-based devices have gained attention because of ultra-conformal adhesion while providing excellent water vapor transmission. Here, a pH sensor tattoo made of temporary tattoo paper, screen-printed poly(3,4-ethylenedioxythiophene):polystyrene sulfonate electrodes, and pH-responsive hydrogel deposited via initiated chemical vapor deposition, is proposed. The tattoo sensor is easily transferred on skin, maintaining full functionality, and shows excellent conformability to topographical features of epidermis. The investigation of the morphology of all layers within the sensor verifies full control of the desired width of electrodes, thickness of hydrogel, and deposition shielded areas. The hydrogel layer exhibits a reversible pH-responsive swelling of 24.7 ± 0.3% to 38 ± 1%, with respect to the dry state, at pH 4 to pH 6, respectively. Impedance spectroscopy identifies the phase shift at 10 and 1000 Hz as an excellent pH-related property of the sensor, which can be only ascribed to the presence of the hydrogel. The sensors ability to be operated with non-sophisticated read-out hardware and software is also demonstrated.
KW - Arduino
KW - biomonitoring
KW - iCVD
KW - smart hydrogel
KW - wearable device
UR - http://www.scopus.com/inward/record.url?scp=85118823628&partnerID=8YFLogxK
U2 - 10.1002/admt.202100717
DO - 10.1002/admt.202100717
M3 - Article
AN - SCOPUS:85118823628
SN - 2365-709X
VL - 7
JO - Advanced Materials Technologies
JF - Advanced Materials Technologies
IS - 5
M1 - 2100717
ER -