Uniform, Large-Area, Highly Ordered Peptoid Monolayer and Bilayer Films for Sensing Applications

The production of atomically defined, uniform, large-area 2D materials remains as a challenge in materials chemistry. Many methods to produce 2D nanomaterials suffer from limited lateral film dimensions, lack of film uniformity, or limited chemical diversity. These issues have hindered the application of these materials to sensing applications, which require large-area uniform films to achieve reliable and consistent signals. Furthermore, the development of a 2D material system that is biocompatible and readily chemically tunable has been a fundamental challenge. Here, we report a simple, robust method for the production of large-area, uniform, and highly tunable monolayer and bilayer films, from sequence-defined peptoid polymers, and their application as highly selective molecular recognition elements in sensor production. Monolayers and bilayer films were produced on the centimeter scale using Langmuir-Blodgett methods and exhibited a high degree of uniformity and ordering as evidenced by atomic force microscopy, electron diffraction, and grazing incidence X-ray scattering. We further demonstrated the utility of these films in sensing applications by employing the biolayer interferometry technique to detect the specific binding of the pathogen derived proteins, shiga toxin and anthrax protective antigen, to peptoid-coated sensors.