As is evident from the lateral-flow-assay (LFA) that became so popular with detection of Corona virus, there is an urgent need to increase the sensitivity of detection of both point-of-care (POC) and self-testing (for example, used by individuals at home) devices. Lateral flow kits result in relatively low detection limit as only a small fraction of the target bioparticles actually interact and bind to the surface immobilized antibodies due to their short passage time and long diffusion time.

We developed a technology for spatio-temporal control of multiple electrokinetically preconcentrated plugs of bioparticles (molecules, virus, bacteria etc.). The technology involves using individually addressable active elements (electro-thermal stirrers or an array of ion-permselective membranes) that can be easily integrated within either a microfluidic chip or a paper strip in LFA format to perform programmable manipulation of multiple electrokinetically preconcentrated plugs of the desired analyte over the sensing areas.

ADVANTAGES OVER EXISTING TECHNOLOGIES
• Simultaneous formation of multiple preconcentrated bioparticle plugs and/or programming of the location of a single plug over multiple sensing locations for enhanced parallelization and/or multiplex sensing.
• Such preconcentration results in enhanced detection sensitivity (i.e. improved limit of detection (LOD))
within various microfluidic devices, including paper based LFA.

APPLICATIONS
• Point-of-care device that enables the use of disposable and cheap chips for rapid and highly sensitive biosensing.
• Applicability of the technique for lateral flow assays (LFA) based on paper strips.
INTELLECTUAL PROPERTY US and EU patents pending

REFERENCES
Park, S. and Yossifon, G., Electrothermal based active control of ion transport in a microfluidic device with an ionpermselective membrane, Nanoscale 10, 11633 – 11641 (2018).
Park, S. and Yossifon, G., Electrothermal active control of preconcentrated biomolecule plugs, Analytical Chemistry (2019).
Park, S., Sabbagh, B., Abu-Rjal, R. and Yossifon, G., Digital Microfluidics-Like Manipulation of Electrokinetically Preconcentrated Bioparticle Plugs in Continuous-Flow, Lab-on-a-chip (2022).