Abstract
Single-walled carbon nanotubes (SWCNTs) emit photostable near-infrared (NIR) fluorescence that is conducive for optical glucose monitoring. Such SWCNT-based optical sensors often require the immobilization of proteins that can confer glucose selectivity and reactivity. In this work, we immobilize a glucose-reactive enzyme, glucose oxidase (GOx), onto SWCNTs using a N-(1-pyrenyl)maleimide (PM) crosslinker via thiol bioconjugation of engineered cysteine residues. We compare the conjugation of several glucose oxidase variants containing rationally-engineered cysteines and identify a D70C variant that shows effective bioconjugation. The bioconjugation was characterized through both absorption and fluorescence spectroscopy. Furthermore, we demonstrate an application for continuous glucose monitoring in the NIR-II optical region using the bioconjugated reaction solution, which shows a reversible response to physiological concentrations of glucose. Finally, we develop a miniaturized NIR-II reader to be used for cell cultures that require continuous glucose monitoring.
Original language | English |
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Pages (from-to) | 2420-2427 |
Number of pages | 8 |
Journal | Nanoscale Advances |
Volume | 4 |
Issue number | 11 |
DOIs | |
Publication status | Published - 4 May 2022 |
ASJC Scopus subject areas
- Bioengineering
- Atomic and Molecular Physics, and Optics
- Chemistry(all)
- Materials Science(all)
- Engineering(all)