Controlling Flow with Light

Research Project, 2026 – 2030

One of the core problems in affinity-based surface biosensors, such as surface plasmon resonance (SPR), is to effectively deliver the target analyte to the sensor at low concentrations, when diffusive transport typically results in impractically long measurement times. The established approach is then to use an external pump to flow analytes across the sensor surface. However, this comes at the expense of considerably increased complexity and cost. We address this issue by exploring NIR photo-thermal excitation of microbubbles for generating Marangoni flows. The project utilizes an invention – miniature NIR metalasers – that will allow us to establish a novel experimental system based on combining Marangoni flow, using arrays of individually controllable metalasers, and SPR. The project will bring new insights of how to superimpose directional Marangoni flows in time and space and it will advance our understanding of these flows through time-dependent quantitative FEM simulations. The proposed project may eventually lead to extremely compact and versatile miniature SPR sensors that do not rely on external pumps. Such devices could have major impact as portable and cost-effective molecular analysis instruments for medical diagnostics, point-of-care bioanalysis, environmental field work, and biological-threat detection.