MICROFLUIDIC MANIPULATION OF COLLOIDAL PARTICLES BY INTERFACIAL FORCES FOR BIOANALYTICAL AND DIAGNOSTICS APPLICATIONS
Date: October 27, 2026 Time: 02:00 PM Location: EE Reading Room
Speaker: Dr. Guido Bolognesi from University College London Supervisor: Dr. Nauman Zaffar Butt
The controlled transport of colloidal particles is of great importance in a broad range of applications, including drug delivery, purification, filtration, sensing and bioanalysis. In this talk, I will present microfluidic approaches that rely on salt concentration gradients to manipulate synthetic and biological particles for material characterisation, analytical and diagnostic applications. Combining experimental analysis with numerical simulations, I will discuss how the interplay between diffusiophoresis and diffusioosmosis – the transport of colloids and liquids induced by salt concentration gradients – enables the reversible trapping and accumulation of particles within dead-end pores, as well as the focusing of colloidal particles within straight open channels under continuous flow. I will then showcase proof-of-concept microdevices that exploit these mechanisms for the continuous size- and surface-chemistry-based separation of polymer particles, and for the measurement of the zeta potential and charged lipid composition of small unilamellar vesicles (SUVs). I will further discuss how the proposed approach can be applied to the detection and separation of protein corona-coated polymer beads from bare particles. Finally, I will show how salt-driven particle manipulation can be implemented in paper-based microfluidic systems and present a novel strategy for enhancing the sensitivity of lateral flow assays based on the on-line manipulation of gold nanoparticles, paving the way for the development of novel diagnostic tools with strong potential for deployment in resource-limited settings.
27
Oct
Date: October 27, 2026
Time: 02:00 PM
Location: EE Reading Room
Speaker: Dr. Guido Bolognesi from University College London
Supervisor: Dr. Nauman Zaffar Butt