A novel electrochemical dopamine sensor was fabricated based on a composite film solely consisting of kappa-carrageenan and hierarchical porous carbon drop-casted onto a glassy carbon electrode in a conventional three electrode system. Graphene oxide was synthesized in a one-step thermal conversion from base-catalyzed alkali lignin. Five ratios by mass of a novel hierarchical porous activated carbon and kappa-carrageenan were studied for dopamine quantification without synthetic binders such as polytetrafluoroethylene. Various tests were performed to explicate structure and electrochemical properties of the films. Utilizing differential pulse voltammetry for detection, the optimized 10:1 ratio system elicited a linear range of 1–250
- Award ID(s):
- 1933861
- NSF-PAR ID:
- 10297912
- Date Published:
- Journal Name:
- RSC Advances
- Volume:
- 11
- Issue:
- 25
- ISSN:
- 2046-2069
- Page Range / eLocation ID:
- 15410 to 15415
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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μ mol l−1and a limit of detection of 0.14μ mol l−1(S/N = 3). Results suggested an effective new combination of materials for non-enzymatic dopamine sensing. -
This study aimed to explore lignin as a naturally occurring aromatic precursor for the synthesis of LIG and further fabrication of ultrasensitive strain sensors for the detection of small deformations. One-step direct laser writing (DLW) induced high quality porous graphene, so called laser induced graphene (LIG), from kraft lignin under the conditions optimized for laser power, focus distance, and lignin loading. An electrode based on the resulting LIG was facilely fabricated by transferring LIG onto an elastomeric substrate ( i.e. , Dragon Skin™). The novel LIG transfer was facilitated by spin coating followed by water lifting, leading to the full retention of porous graphene onto the elastomeric substrate. The strain sensor was shown to be highly sensitive to small human body motions and tiny deformations caused by vibrations. It had a working range of up to 14% strain with a gauge factor of 960 and showed high stability as evidenced by repetitive signals over 10 000 cycles at 4% strain. The sensor was also successfully demonstrated for detecting human speaking, breath, seismocardiography (SCG), and movement of pulse and eye. Overall, the lignin-derived LIG can serve as excellent piezoresistive materials for wearable, stretchable, and ultrasensitive strain sensors with applications in human body motion monitoring and sound-related applications.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1RA00735A
