Binding of Peptides to Graphene

Peptides are known to have molecular recognition properties but there has not been a lot of research done based on using peptides in the fabrication of biosensors. In that direction, this thesis aims to explore how peptides can be used to functionalize a graphene substrate. Graphene has excellent electronic mobility, conductivity and strength that make it a suitable choice of substrate for a biosensor. Using a particular sequence of peptide that has been identified by phage display methods to bind to graphene, various modifications are done to the original sequence to study and analyze the selectivity of this peptide in binding. Quantum dots are used to qualitatively verify whether binding occurs or not by imaging the re-emission of incident light under a fluorescence microscope. It has been observed that the peptide sequence is extremely selective and that any modification to its sequence hampers binding. Introducing aromaticity and additional polarity in the sequence does not favor binding. In conclusion, there is a promising future for graphene-based, peptide-functionalized nano biosensors that have improved sensitivity and speeds when compared to sensors available today.