TY - JOUR
T1 - Precise positioning of enzymes within hierarchical polymer nanostructures for switchable bioelectrocatalysis
AU - Qu, Fengjin
AU - Ma, Xiaoyan
AU - Gautrot, Julien E.
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/5/1
Y1 - 2021/5/1
N2 - The ability to reversibly switch bioelectrocatalytic sensors is attractive for the design of biomonitoring platforms displaying a complex environmental response, or for the protection of biosensors. However, the retention of reversible biocatalytic properties upon multiple environmental cycles, with broad detection range, low signal-to-noise and limit of detection remains challenging. In this report, we demonstrate the precise positioning of the enzyme glucose oxidase within block-copolymer brush nanostructures, via the re-initiation of N-isopropylacrylamide (NIPAM) polymerisation from enzyme-decorated poly(dimethylaminoethyl methacrylate) (PDMAEMA) blocks. We find that the precise design of polymer brush grafting density, thickness and crosslinking of the PNIPAM block enables the stable positioning of biocatalytic sites close to electrode surfaces. The control of the polymer brush nanostructure, its conformation and the distribution of biocatalytic sites is characterised via a combination of in situ ellipsometry, X-ray photoelectron spectroscopy, grazing angle FTIR and surface plasmon resonance. In turn, cyclic voltammetry and electrochemical impedance spectroscopy demonstrate that such control of the polymeric nanostructures confers a unique combination of low limit of detection (23.9 μM), a broad dynamic range of glucose sensing (0.05–12.8 mM) and true “OFF” state upon pH or thermal stimulation, whilst retaining excellent performance over repeated switching cycles of the sensor. Therefore, hierarchical biocatalytic polymer brushes display unique properties for the design of responsive biosensors and complex multi-functional gating platforms.
AB - The ability to reversibly switch bioelectrocatalytic sensors is attractive for the design of biomonitoring platforms displaying a complex environmental response, or for the protection of biosensors. However, the retention of reversible biocatalytic properties upon multiple environmental cycles, with broad detection range, low signal-to-noise and limit of detection remains challenging. In this report, we demonstrate the precise positioning of the enzyme glucose oxidase within block-copolymer brush nanostructures, via the re-initiation of N-isopropylacrylamide (NIPAM) polymerisation from enzyme-decorated poly(dimethylaminoethyl methacrylate) (PDMAEMA) blocks. We find that the precise design of polymer brush grafting density, thickness and crosslinking of the PNIPAM block enables the stable positioning of biocatalytic sites close to electrode surfaces. The control of the polymer brush nanostructure, its conformation and the distribution of biocatalytic sites is characterised via a combination of in situ ellipsometry, X-ray photoelectron spectroscopy, grazing angle FTIR and surface plasmon resonance. In turn, cyclic voltammetry and electrochemical impedance spectroscopy demonstrate that such control of the polymeric nanostructures confers a unique combination of low limit of detection (23.9 μM), a broad dynamic range of glucose sensing (0.05–12.8 mM) and true “OFF” state upon pH or thermal stimulation, whilst retaining excellent performance over repeated switching cycles of the sensor. Therefore, hierarchical biocatalytic polymer brushes display unique properties for the design of responsive biosensors and complex multi-functional gating platforms.
KW - Bioelectronics
KW - Enzymatic catalysis
KW - Polymer brush
KW - Stimuli-responsive polymer
KW - Surface-initiated ATRP
UR - http://www.scopus.com/inward/record.url?scp=85101198388&partnerID=8YFLogxK
U2 - 10.1016/j.bios.2021.113045
DO - 10.1016/j.bios.2021.113045
M3 - 文章
C2 - 33639348
AN - SCOPUS:85101198388
SN - 0956-5663
VL - 179
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
M1 - 113045
ER -