Computational, electrochemical, and spectroscopic, studies of acetycholinesterase covalently attached to carbon nanotubes

• Published in: Colloids and surfaces, B, Biointerfaces Vol. 103; pp. 624 - 629
• Main Authors: Cabral, Murilo F., Barrios, Joseph D., Kataoka, Erica M., Machado, Sergio A.S., Carrilho, Emanuel, Garcia, Carlos D., Ayon, Arturo A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-03-2013
• Subjects: Acetilcholinesterase; acetylcholinesterase; Acetylcholinesterase - chemistry; Acetylcholinesterase - metabolism; Animals; Binding Sites; Carbon nanotubes; colloids; Computational docking; Computer Simulation; Covalent binding; Cyclic voltammetry; Dielectric Spectroscopy; EIS; electrochemistry; Electrochemistry - methods; electrodes; electron transfer; Electrophorus - metabolism; energy; FT-IR; immobilized enzymes; infrared spectroscopy; Nanotubes, Carbon - chemistry; physicochemical properties; Protein Binding; Protein Structure, Secondary; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared; Cyclic voltammetry; Computational docking; Acetilcholinesterase; Carbon nanotubes; FT-IR; Covalent binding; EIS
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2012.08.039

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► In-silico simulations enabled the identification of the binding site and the calculation of the interaction energy. ► Further insight about the interaction carbon nanotubes/AChE and its behavior observed by means of Electrochemical and Spectroscopic measurements. ► Better understanding of the physical and chemical parameters involved in the development of nanocomposites based on enzymes and carbon nanotubes.
This manuscript describes results related to the characterization of electrodes modified with a composite of acetylcholinesterase covalently bound to carbon nanotubes (CNT). The characterization was performed by computational methods and complemented by cyclic voltammetry, infrared spectroscopy, and electrochemical impedance spectroscopy. In-silico simulations enabled the identification of the binding site and the calculation of the interaction energy. Besides complementing the computational studies, experimental results obtained by cyclic voltammetry showed that the addition of CNT to the surface of electrodes yielded significant increases in effective area and greatly facilitated the electron transfer reactions. These results are also in agreement with impedance spectroscopy data, which indicated a high apparent rate constant, even after the immobilization of the enzyme. These results lend new information about the physical and chemical properties of biointerfaces at the molecular level, specifically about the mechanism and consequences of the interaction of a model enzyme with CNT.