Site-Specific Protein Photochemical Covalent Attachment to Carbon Nanotube Side Walls and Its Electronic Impact on Single Molecule Function

Abstract

Dafydd 2020. Site-specific protein photochemical covalent attachment to carbon nanotube side walls and its electronic impact on single molecule function. Bioconjugate Chemistry 31 (3) , pp.

DNA-Directed Assembly of Carbon Nanotube–Protein Hybrids

“…The GFP variant containing the non-canonical amino acid p-azido-L-phenylalanine (AzF) in place of residue Gln204 (Figure S2) was generated as described previously using an expanded genetic code approach [36][37][38]. The variant, termed GFP 204AzF , was used because the AzF (and thus the linking site) lies close to the chromophore of GFP and has previously been shown to retain function on the attachment to SWCNTs and DNA [7,11,38]. To functionalize GFP with DNA, amine-modified DNA was reacted with BCN-NHS ester (see Figure S3 for details).…”

“…This has been shown to have significant effects in the protein/SWCNT interactions. Zubkovs et al and Thomas et al [11,21] have shown how the site-specific attachment of a fluorescent protein affects the optical behavior of both protein and SWCNTs; this was demonstrated by investigating the change in a fluorescent protein function and, in the case of Zubkovs et al, of (7,6) SWCNTs within a mixture of nanotubes. There are other examples of changes in the fluorescent behavior of SWCNTs due to biofunctionalization, but these investigations are typically carried out with unsorted SWCNTs; hence, the interaction can only be considered an average response to each species in the mixture.…”

“…The optical and electronic properties of single-walled carbon nanotubes (SWCNTs) have long been the focus of nanomaterials research, including the design of biosensors [1][2][3][4][5]. Consequently, modifying SWCNTs with biorecognition elements or biomolecules themselves is a key step in this process [6][7][8][9][10][11], and the functionalization of SWCNTs has been tailored through both covalent and non-covalent approaches [12][13][14][15][16][17][18][19][20].…”

“…In recent years, different studies have demonstrated the importance of controlling the position and orientation of the biomolecule relative to the SWCNT: biomolecules, and particularly proteins, are not uniform structures, as nanoparticles are, and therefore the point at which they are tethered is important to consider [7,11,21]. This has been shown to have significant effects in the protein/SWCNT interactions.…”

Single molecule electronic devices with carbon-based materials: status and opportunity

“…13). 60 Depending on the position of the protein on the CNT side wall, GFP function switched from GFP LA and GFP SA , which resulted in a change of the fluorescence wavelength.…”