Abstract: Methods and devices for detecting a target agent of interest, e.g., a pathogen, in a sample are described herein. In some embodiments, a sensor is provided that can include a substrate, a graphene layer disposed on a surface of said substrate, and a protein bound to said graphene layer. The protein can be capable of binding to one or more target agents of interest, e.g., pathogens, etc. The binding of the protein to the one or more target agents of interest can generate a change in an electrical property of the graphene layer.

Abstract: In one aspect, a method of detecting a pathogen, e.g., listeria bacterium, chlamydia bacteria, gonorrhea bacteria and/or HPV, in a sample is disclosed, which comprises bringing a sample into contact with a graphene layer functionalized with an antibody exhibiting specific binding to the pathogen, monitoring electrical resistance of said antibody-functionalized graphene layer in response to interaction with said sample, and detecting presence of the pathogen in said sample by detecting a change in said electrical resistance indicative of interaction of the pathogen with said antibody-functionalized graphene layer. For example, a decrease of the electrical resistance of the graphene layer can indicate the presence of the pathogen in the sample under study. In some embodiments, a method according to the present teachings is capable of detecting pathogens, such as listeria bacteria, chlamydia bacteria, gonorrhea bacteria and HPV in a sample at a concentration as low as 4 cfu per 100 grams of a sample.