Multimodal Non-Destructive Microfluidic Sorting of Microbes for Elemental Analysis

Rare Earth Elements (REEs) are essential for modern electronics and defense systems, yet the US is dependent on foreign sources for these compounds. This proposed work will create an economical and efficient method for harvesting REE from domestic soil and waste sources by enabling high throughput methods of identifying microbes, in complex media, that are capable of uptaking REEs through biological mechanisms. This project’s central hypothesis is that multidimensional optical sensing, including laser-induced fluorescence, can be used to quantify microbial REE content in a high-throughput fashion. This project’s objectives include (1) Quantifying the optical signatures of pure and mixed REEs, as well as their signatures when mixed with enhancing additive agents, as well as those additives’ impact on the integrity of the microbes’ DNA; (2) Conducting yeast uptake experiments, in which yeast that preferentially uptake REEs will be used, as compared to wild type yeast, for validation and verification of the proposed sensor; (2) Designing a prototype sorting system, in which data from our preliminary experiments will be used to perform a tradespace analysis of the sorting method and detection system; and (4) Building and validating a prototype system, in which a low fluorescence microfluidics chip or colony plate will be fabricated and integrated and validated with Brimrose’s sensing system. Major deliverables include (1) Reports summarizing the results of our signature analyses, tradespace analyses, and ground-truthing methods; (2) A report summarizing the experimental validation of the breadboard prototype and sources of error; and (3) Algorithms associated with the microfluidics control and classification of microbes based on the measured signals. Upon the successful completion of the program, we will proceed to design a second-generation embodiment in preparation for Phase II.