Abstract
Supramolecular conjugates of single-walled carbon nanotubes and glucose oxidase were prepared in aqueous solution using ultrasonication processing and then isolated by high-speed centrifugation. The conjugates of the single-walled carbon nanotubes and the pristine glucose oxidase, serving as control, were investigated for their enzymatic bioactivity. In addition, the effect of the extent of ultrasonication was studied. The conjugates were also characterized by UV–VIS and circular dichroism spectroscopy as well as by high-resolution transmission electron microscopic and thermogravimetric analysis. Ultrasonication is shown to reduce catalytic activity by ca. 30% (10 min) and that prolonged ultrasonication (up to 60 min) further reduces V max by 40%. However, most of this decrease arises from ultrasonication itself. The presence of carbon nanotubes (CNTs), while not eliminating changes in catalytic activity, mitigates the magnitude of these changes and is effectively de-bundled by the presence of the surfactant properties of the protein. The enzymatic activity and conformation were found to be predominantly retained after the supramolecular conjugation process assisted by ultrasonication in the presence of the CNTs.
Similar content being viewed by others
References
Loiseau A, et al. Understanding carbon nanotubes from basics to applications. Lecture notes in physics. Heidelberg: Springer; 2006.
Geckeler KE, Rosenberg E. Functional nanomaterials. Valencia: American Scientific; 2006.
Dodziuk H. Cyclodextrins and their complexes. Weinheim: Wiley-VCH; 2006.
Steed JW, Turner DR, Wallace KJ. Core concepts in supramolecular chemistry and nanochemistry. West Sussex: Wiley; 2007.
Kumar CSSR. Nanomaterials for biosensors. Nanotechnologies for the life sciences. Weinheim: Wiley-VCH; 2007.
Kim D, Nepal D, Geckeler KE. Individualization of single-walled carbon nanotubes: is the solvent important? Small. 2005;1(11):1117–24. doi:10.1002/smll.200500167.
O'Connell MJ, et al. Band gap fluorescence from individual single-walled carbon nanotubes. Science. 2002;297(5581):593–6. doi:10.1126/science.1072631.
Kovtyukhova NI, et al. Individual single-walled nanotubes and hydrogels made by oxidative exfoliation of carbon nanotube ropes. J Am Chem Soc. 2003;125(32):9761–9. doi:10.1021/ja0344516.
Kumar CSSR. Biofunctionalization of nanomaterials. In: Kumar CSSR, editor. Nanotechnologies for the life sciences. Weinheim: Wiley-VCH; 2006.
Guiseppi-Elie A, Lei C, Baughman RH. Direct electron transfer of glucose oxidase on carbon nanotubes. Nanotechnology. 2002;13(5):559–64. doi:10.1088/0957-4484/13/5/303.
Patolsky F, et al. C60-mediated bioelectrocatalyzed oxidation of glucose with glucose oxidase. J Electroanal Chem. 1998;454(1–2):9–13. doi:10.1016/S0022-0728(98)00257-5.
Davis JJ, Coleman KS, Azamian BR, Baqshaw CB, Green ML. Chemical and biochemical sensing with modified single walled carbon nanotubes. Chem Eur J. 2003;9(16):3732–9. doi:10.1002/chem.200304872.
Liang W, Zhuobin Y. Direct electrochemistry of glucose oxidase at a gold electrode modified with single-wall carbon nanotubes. Sensors. 2003;3(3):544–54. doi:10.3390/s31200544.
Cai C, Chen J. Direct electron transfer of glucose oxidase promoted by carbon nanotubes. Anal Biochem. 2004;332(1):75–83. doi:10.1016/j.ab.2004.05.057.
Liu Y, et al. The direct electron transfer of glucose oxidase and glucose biosensor based on carbon nanotubes/chitosan matrix. Biosens Bioelectron. 2005;21(6):984–8. doi:10.1016/j.bios.2005.03.003.
Geckeler KE. Advanced macromolecular and supramolecular materials and processes. New York: Kluwer; 2003.
Mason TJ, Lorimer JP. Applied sonochemistry: uses of power ultrasound in chemistry and processing. Weinheim: Wiley-VCH; 2002.
Dhriti Nepal KG. pH-sensitive dispersion and debundling of single-walled carbon nanotubes: lysozyme as a tool. Small. 2006;2(3):406–12. doi:10.1002/smll.200500351.
Dhriti Nepal KG. Proteins and carbon nanotubes: close encounter in water. Small. 2007;3(7):1259–65. doi:10.1002/smll.200600511.
Bergmeyer HU, Gawehn K, Grassl M. Methods of enzymatic analysis. New York: Academic; 1974. p. 457–458.
Yang JT, Wu CS, Martinez HM. Calculation of protein conformation from circular dichroism. Methods Enzymol. 1986;130:208–269.
Kim JB, Premkumar T, Giani O, Robin J-J, Schue F, Geckeler KE. A mechanochemical approach to nanocomposites using single-wall carbon nanotubes and polyL-lysine. Macromol Rapid Commun. 2007;28(6):767–71. doi:10.1002/marc.200600802.
Denslow ND, Wingfield PT, Rose K. Overview of the characterization of recombinant proteins. Current Protocols in Protein Science 1994;7.1.1–7.1.13
Bateman RC Jr, Evans JA. Using the glucose oxidase/peroxidase system in enzyme kinetics. J Chem Educ. 1995;72(12):A240–1.
Simpson C, et al. Isolation, purification and characterization of a novel glucose oxidase from Penicillium sp. CBS 120262 optimally active at neutral pH. Protein Expr Purif. 2007;51(2):260–6. doi:10.1016/j.pep.2006.09.013.
Shah S, Solanki K, Gupta M. Enhancement of lipase activity in non-aqueous media upon immobilization on multi-walled carbon nanotubes. Chemistry Central Journal. 2007;1(1):30. doi:10.1186/1752-153X-1-30.
Acknowledgments
This work was supported by the US Department of Defense (DoDPRMRP) grant PR023081/DAMD17-03-1-0172 and by the Consortium of the Clemson University Center for Bioelectronics, Biosensors and Biochips. KEG thanks the Clemson C3B for a Visiting Professorship and SHC for a transient graduate studentship as well as support from the Dasan Global Explorer Program (GIST, South Korea).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Guiseppi-Elie, A., Choi, SH., Geckeler, K.E. et al. Ultrasonic Processing of Single-Walled Carbon Nanotube–Glucose Oxidase Conjugates: Interrelation of Bioactivity and Structure. Nanobiotechnol 4, 9–17 (2008). https://doi.org/10.1007/s12030-009-9026-4
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12030-009-9026-4