Improving high-throughput surface tension measurements — with Spark Fund Awardee Assistant Professor Sara M. Hashmi

Nov 18, 2022 | Innovation, Spark Fund

Sara M. HashmiMicrofluidic droplet technology is an exciting, multi-faceted research field that can encapsulate biological particles for a vast array of biomedicine and biotechnology applications, such as microparticle synthesis, molecular detection, diagnostics, and drug delivery.

For example, many microfluidic droplet-generating devices are used for genetic sequencing and searching for drug targets through DNA and RNA studies.

Microfluidic droplet and particle generation techniques are quickly becoming mainstream, with several commercial instruments now available.

However, these devices are currently limited to research purposes because they only operate in a narrow window of conditions. Furthermore, there is no single, reliable way to remove the particle or droplet products from the device while ensuring they remain stable. If transferred, the particles and droplets are at risk of aggregation, coalescence, or adhesion to the device’s channel walls.

That means the technology may be useless for downstream testing or collection for external use, especially as the technology is scaled up.

Assistant Professor Sara M. Hashmi and her team at The Hashmi Complex Fluids Lab are working to solve this problem.

The lab’s focus is to incorporate a validated droplet tensiometer, for measuring surface tension, and a particle “elastometer,” for measuring particle elasticity (or softness), into commercially available particle- and droplet-generating fluidic device designs. These designs will enable high-throughput measurements of surface tension or elasticity without requiring the particles or droplets to be transferred from the device. Their method also enables more concentrated samples to be measured at higher throughput and with less material waste.

This technological innovation has earned them selection as one of the Spring 2022 Spark Fund awardees.

Technological approach

Hashmi’s technological approach is to screen for droplet or particle instability using an in-line tensiometer/elastometer downstream of microfluidic droplet or particle generation junctions. They do this by using Taylor’s small deformation theory to relate the elongation of droplets in flow to their surface tension.

Their results show that Taylor’s theory can be used in the context of pressure-driven, high-throughput flows through rectangular cross-section fluidic devices, which is an exciting result for the team.

They’ve also demonstrated that Taylor’s theory holds true for pressure-driven flows through rectangular channels, even when droplets or particles span nearly the entire channel height.

Microfluidics provides a relatively cheap, easily customizable method to make tools for a wide variety of studies. Therefore, they are an excellent platform for any projects involving the flow of microparticles, polymers, or other suspended materials.

The broad applications of this technology mean that there are many opportunities for collaborative studies beyond emulsions, including other novel materials or biological specimens representing various disease states.

Commercialization with the Spark Fund

Droplet- or particle-generating devices are industrial players in the biomedical and genomics spaces. These devices are able to identify new targets for drug delivery, develop pharmaceuticals, and make new materials.

As such, the Hashmi Lab technology could enable a wide variety of products with great societal impact.

Beyond improving microfluidic droplet making, their tool could be scaled up and used to screen for various disease states, including diabetes and metastatic cancers.

“Making a positive impact in real-time in situ cancer screening would be an amazing outcome of this research,” says Assistant Professor Hashmi.

The worldwide market for droplet-based and other microfluidics technologies is projected to grow to nearly $60B USD by 2026, with North America accounting for 40% of this market. Segments of this market include microfluidic devices, flow controllers, valves, sensors, pumps, and other components.

“As an academic, thoughts of commercialization or technology licensing are not always in the front of my mind, nor do I have training in business or entrepreneurship,” says Hashmi. “I have already learned a lot from the CRI team about how to think about these broader challenges and how to talk to people interested in products in a way that brings cool science to life.”

Learn more about Professor Hashmi’s research and the other Spark Fund Award grantees here.

Written by Elizabeth Creason