The main objective of this SBIR project is to develop a continuous water sensor that can detect and quantify the concentration of pesticides in real-time. The project will aim to integrate nanobody technology with an existing customizable biosensor platform (the Qube) that uses engineered microbial sensor strains paired with microfluidic technology to continuously monitor water for common contaminants and other agriculturally relevant targets (e.g. nitrate). In previous work, we have developed this platform to quickly and accurately measure the concentration of heavy metals and nutrients in water continuously for over a month without requiring subjective interpretation, extensive calibration, or regular oversight. A simple monthly cartridge and media swap enables the sensor to run indefinitely, reporting the toxin concentrations to a mobile friendly portal. The work proposed here will develop a novel nanobody-based approach to expand the func- tionality of this sensor platform, which will enable the detection of almost any type of contaminant that can be recognized by a nanobody. That is, while the project leverages an existing water sampling platform along with a computational backbone for analyzing cellular responses in real-time, the development of an innovative approach to nanobody-based biosensor strain development will be transformative and broadly impactful. We will begin by developing the capability to detect chlorpyrifos as proof of principal in Phase I, with a plan expand to other pesticides and emerging contaminants as well as perform field validations of the platform with relevant end-users in Phase II.