Assessing magnetic particle content in algae using compact time domain nuclear magnetic resonance

The characterization of algae biomass is essential for ensuring the health of an aquatic ecosystem. Algae overgrowth can be detrimental to the chemical composition of a habitat and affect the availability of safe drinking water. In-situ sensors are commonplace in ocean and water quality monitoring scenarios where the collection of field data using readily deployable, cost-effective sensors is required. For this purpose, the use of compact time domain nuclear magnetic resonance (TD-NMR) is proposed for the assessment of Magnetic Particle (MP) content in algae. A custom NMR system capable of rapidly acquiring relaxometric data is introduced, and the T2 relaxation curves of algae samples sourced from Lake Wateree in South Carolina are analyzed. A clear correlation between the relaxation rate and MP concentration of the samples is observed, and the viability of the proposed scheme for MP-based estimations concerning algae is discussed.