SBIR Phase II: Developing the First Flow-Through Sensor for Real Time Microplastics Measurements

The broader/commercial impact of this Small Business Innovation Research (SBIR) Phase II project is to revolutionize microplastics detection with the development of the first near real-time automated in-situ sensor. Unlike existing sensors that take hours to days for a single sample, this technology promises quick and cost-effective analysis of microplastics abundance in water samples. This technology can enable communities nationwide to monitor drinking water and characterize undersampled environments and sources of human exposure to microplastics pollution. Given the alarming environmental and human health implications of microplastic contamination, a rapid and affordable sensor is crucial to the NSF’s broader impact goal of advancing the health and welfare of the American public. The commercial sensor caters to scientists, drinking water providers, monitoring facilities, conservation organizations, and health professionals, facilitating widespread access to microplastics data. The goal of this project is to create an ultrasound-based sensor that can detect and characterize microplastics in water or other fluids. Traditional optical-based methods for microplastic detection are time-consuming, labor-intensive, and expensive, and cannot detect the smallest microplastics that are most harmful to human health and environmental systems. Traditional ultrasonic particle detectors use reflection and scattering to detect particles based on the material's different bulk modulus (compression resistance) compared to that of the fluid. However, the bulk modulus of plastic is similar to that of water. This project utilizes a novel detection method inspired by tomography and interferometry to measure spectral differences as a function of concentration and composition of microplastics, even for the smallest of microplastics. The method leverages observables from multiple physical processes including scattering, reflection, absorption, attenuation, and resonance in order to empirically map the received ultrasonic energy to concentration and composition of suspended particulates in a fluid sample. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.