Virus directed assembly of receptor peptides for explosive sensing

Abstract-Protein engineering is a rich technology that can be used for chemical vapor detection applications. By utilizing the high specificity and programmability offered by genetic engineering of proteins, a highly selective receptor layer targeting trinitrotoluene (TNT) vapor is developed. This receptor layer consists of a scaffolding made of Tobacco mosaic virus (TMV), whose virus coat protein has been mutated to express cysteine residues and sequence specific peptides to enhance virus self-assembly and selective binding to TNT molecules, respectively. The virus-based receptor layer was assembled on to quartz crystal microbalances (QCMs) for TNT vapor sensing. A 300% increase in TNT attachment was observed on the receptor layer compared to an uncoated QCM. The mass resolution limit was determined to be 3.2ng, limited by the minimum resolution of the current setup. This development demonstrates the potential for programmable viruses to be used as a receptor layer template.