title: Versatile multi-functionalization of protein nanofibrils for biosensor applications.
abstract: Protein nanofibrils offer advantages over other nanostructures due to the ease in their self-assembly and the versatility of surface chemistry available. Yet, an efficient and general methodology for their post-assembly functionalization remains a significant challenge. We introduce a generic approach, based on biotinylation and thiolation, for the multi-functionalization of protein nanofibrils self-assembled from whey proteins. Biochemical characterization shows the effects of the functionalization onto the nanofibrils' surface, giving insights into the changes in surface chemistry of the nanostructures. We show how these methods can be used to decorate whey protein nanofibrils with several components such as fluorescent quantum dots, enzymes, and metal nanoparticles. A multi-functionalization approach is used, as a proof of principle, for the development of a glucose biosensor platform, where the protein nanofibrils act as nanoscaffolds for glucose oxidase. Biotinylation is used for enzyme attachment and thiolation for nanoscaffold anchoring onto a gold electrode surface. Characterization via cyclic voltammetry shows an increase in glucose-oxidase mediated current response due to thiol-metal interactions with the gold electrode. The presented approach for protein nanofibril multi-functionalization is novel and has the potential of being applied to other protein nanostructures with similar surface chemistry.
authors: MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand. luigi.sasso@canterbury.ac.nz.
authors: L
authors: L
authors: Sasso
authors: S
authors: S
authors: Suei
authors: L
authors: L
authors: Domigan
authors: J
authors: J
authors: Healy
authors: V
authors: V
authors: Nock
authors: M A K
authors: MA
authors: Williams
authors: J A
authors: JA
authors: Gerrard
mesh_terms: D000588:Amines / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D001710:Biotin / Q000737:chemistry; D019921:Biotinylation; D003432:Cross-Linking Reagents / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D005947:Glucose / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D008894:Milk Proteins / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D045663:Quantum Dots; D019809:Streptavidin / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties; D000067816:Whey Proteins
chemical_list: D000588:Amines; D003432:Cross-Linking Reagents; D008894:Milk Proteins; D013438:Sulfhydryl Compounds; D000067816:Whey Proteins; D001710:Biotin; D006046:Gold; D019809:Streptavidin; D005949:Glucose Oxidase; D005947:Glucose