Molecular Interactions between Graphene and Biological Molecules

Abstract

Applications of graphene have extended into areas of nanobio-technology such as nanobio-medicine, nanobio-sensing, as well as nanoelectronics with biomolecules. These applications involve interactions between proteins, peptides, DNA, RNA etc. and graphene, therefore understanding such molecular interactions is essential. For example, many applications based on using graphene and peptides require peptides to interact with (e.g., noncovalently bind to) graphene at one end, while simultaneously exposing the other end to the surrounding medium (e.g., to detect analytes in solution). To control and characterize peptide behavior on a graphene surface in solution is difficult. Here we successfully probed the molecular interactions between two peptides (cecropin P1 and MSI-78(C1)) and graphene in situ and in real-time using sum frequency generation (SFG) vibrational spectroscopy and molecular dynamics (MD) simulation. We demonstrated that the distribution of various planar (including aromatic (Phe, Trp, Tyr, and His)/amide (Asn and Gln)/Guanidine (Arg)) side-chains and charged hydrophilic (such as Lys) side-chains in a peptide sequence determines the orientation of the peptide adsorbed on a graphene surface. It was found that peptide interactions with graphene depend on the competition between both planar and hydrophilic residues in the peptide. Our results indicated that part of cecropin P1 stands up on graphene due to an unbalanced distribution of planar and hydrophilic residues, whereas MSI-78(C1) lies down on graphene due to an even distribution of Phe residues and hydrophilic residues. With such knowledge, we could rationally design peptides with desired residues to manipulate peptide-graphene interactions, which allows peptides to adopt optimized structure and exhibit excellent activity for nanobio-technological applications. This research again demonstrates the power to combine SFG vibrational spectroscopy and MD simulation in studying interfacial biological molecules.

Bioelectronics and Interfaces Using Monolayer Graphene

“…The modulation of charge at the graphene‐liquid interface is possible by the attachment of a broad range of organic or inorganic chemical functionalities to the graphene surface . This allows the realization of sensors for targets like DNA, peptides, and proteins ,. As in carbon electrodes, the interfacial charge of graphene is modulated by the presence of chemical moieties covalently or non‐covalently attached to the surface.…”

A Facile Method for the Non-Covalent Amine Functionalization of Carbon-Based Surfaces for Use in Biosensor Development

“…Affinity biosensor manufacture requires bio-functionalization of the graphene surface with an analyte-specific receptor [ 5 ]. Adsorption of proteins to a graphene surface for use in biosensors requires the protein to remain in a particular conformation, ensuring one part of the protein is in contact with the graphene surface (required for adsorption stability and electron doping) and another specific part is exposed to the solvent/solution phase (required for receptor-analyte binding) [ 6 , 7 ]. Protein adsorption to a surface is a complicated process involving van der Waals, hydrophobic, and electrostatic interactions, and hydrogen bonding [ 8 ], with process conditions, such as ionic strength, pH, and temperature also contributing factors [ 9 ].…”

“…Protein adsorption to a surface is a complicated process involving van der Waals, hydrophobic, and electrostatic interactions, and hydrogen bonding [ 8 ], with process conditions, such as ionic strength, pH, and temperature also contributing factors [ 9 ]. Non-covalent interactions between proteins and graphene depend on the binding affinity of various residues in the protein as well as the distribution of the residues [ 6 ] and it has not been explicitly shown that a protein remains functional after adsorption onto graphene surfaces [ 10 ]. Therefore, different unique proteins could interact differently with the graphene surface, potentially affecting the proteins’ structure and binding capability.…”

The Significant Role of NiO in Enhancing the Electrocatalytic Activity of the Pyrolysis Products of the Mixture Containing PdO and Multiwalled Carbon Nanotubes for EOR

“…It is well known that being used as a catalyst support is the main application of carbon nanotubes (CNTs) in the field of fuel cells mainly due to its advantages such as the simple preparation process, high specific surface area, higher electric conductivity, good thermal and chemical stability . Recently, the large‐scale application of CNTs has become a reality because of the sharp decline in the CNTs preparation cost, as compared to some novel kinds of carbon like carbon nanofiber and graphene . Thus, expanding the applications of CNTs has turned into a hot topic especially for the CNTs‐related electrochemical researchers …”