Abstract
In the present study, a glucose oxidase (GluOx) direct electron transfer was realized on an aminated polyethylene glycol (mPEG), carboxylic acid functionalized multi-walled carbon nanotubes (fMWCNTs), and ionic liquid (IL) composite functional polymer modified glassy carbon electrode (GCE). The amino groups in PEG, carboxyl groups in multi-walled carbon nanotubes, and IL may have a better synergistic effect, thus more effectively adjust the hydrophobicity, stability, conductivity, and biocompatibility of the composite functional polymer film. The composite polymer membranes were characterized by cyclic voltammetry (CV), ultraviolet-visible (UV-Vis) spectrophotometer, fluorescence spectroscopy, electrochemical impedance spectroscopy (EIS), and transmission electron microscopy (TEM), respectively. In 50 mM, pH 7.0 phosphate buffer solution, the formal potential and heterogeneous electron transfer constant (ks) of GluOx on the composite functional polymer modified GCE were −0.27 V and 6.5 s−1, respectively. The modified electrode could recognize and detect glucose linearly in the range of 20 to 950 μM with a detection limit of 0.2 μM. The apparent Michaelis-Menten constant (Kmapp) of the modified electrode was 143 μM. The IL/mPEG-fMWCNTs functional polymer could preserve the conformational structure and catalytic activity of GluOx and lead to high sensitivity, stability, and selectivity of the biosensors for glucose recognition and detection.
Highlights
Glucose oxidase (GluOx) is a glycoprotein with a molecular weight of about 150 to 180 kDa, which has attracted special attention due to its wide application in various fields, including food, textile industry, biofuel cells, health, and medical systems [1,2,3,4]
Conformational changes of glucose oxidase (GluOx) may occur due to the strong hydrophobicity and poor biocompatibility of some nanomaterials, which result in poor selectivity of the modified electrodes and limits their actual usage [32,33]
The improvement of biocompatibility of modified materials has become the key focus of direct electrochemical research
Summary
Glucose oxidase (GluOx) is a glycoprotein with a molecular weight of about 150 to 180 kDa, which has attracted special attention due to its wide application in various fields, including food, textile industry, biofuel cells, health, and medical systems [1,2,3,4]. The direct electrochemical study of GluOx has drawn great interest because this research can be helpful tin understanding the process of electron transfer in biological systems, and helpful in manufacture of third generation biosensors or other electrochemical devices [5,6,7,8,9,10,11]. The improvement of biocompatibility of modified materials has become the key focus of direct electrochemical research. Carbon nanotubes have become high performance materials for electrode modification because of their unique structure, and electrical and mechanical properties [34,35]. Due to the poor dispersion of carbon nanotubes in the coating solution, the structural consistency of the modified materials is affected
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
