A key challenge in bioassays is the capturing of a target from a complex matrix. We propose to develop a new sample preparation and pre-concentration microfluidic technique from complex mixtures that uses functionalized magnetic beads guided by soft-magnetic structures and rotating magnetic fields to mix and collect specific reagents. A mesoscale computational model will be developed to study the key characteristics of the capture process. The long term objective is to develop a practical compact portable pre-concentration and pathogen purification system for complex mixtures important for food and environmental safety that can be applied to a wide range of assays.
Intellectual Merit: A fundamental limitation of sampling with magnetic beads is low efficiency of target capture. Optimal operation conditions for magnetic-guided sample preconditioning microfluidic systems leading to high capture efficiency will be established as a function of the size of the target relative the bead, the relative flow and bead velocity, adhesion forces between the target and bead and other factors.
Broader Impact: The overall objective is to demonstrate efficient sampling from a complex matrix real world sample of relevance to food safety. Utilizing rotating external magnetic fields and microscale soft magnetic features the movement and placement of magnetic beads can be manipulated to improve target capture. This novel method will have significant impact on many types of bioassays where a target analyte is at low concentration or where the sample matrix is complex including clinical assays. Interdisciplinary and Education Impact: This interdisciplinary research on bead based sampling and mixing requires expertise in mechanical engineering, electrical engineering and food science. Application of the optimized experimental fluidic device to the detection of pathogens in food samples at the Center for Food Safety at University of Georgia will be demonstrated. This work will have significant impact on many types of bioassays including clinical assays, where a target is at low concentration in a complex matrix is complex. This project will involve and train graduate and undergraduate students, high school teachers and high school students.
