Experimental and Numerical Investigation of Particle Capture for Agglutination-Based NP detection Using the Vibration-Induced Flow.

Nanoparticle (NP) detection is widely used in various fields, such as disease diagnosis and monitoring. We have been developing an NP detection system that utilizes the local flow induced around the oscillating micropillar. The advantage of this system lies in its simplicity and high sensitivity to detect and quantify NPs based on the agglutination of affinity capture particles (CPs) specific to target NPs. In this study, we investigated the dependence of the flow field on agglutination through both experimental and numerical approaches. We observed a similar trend in both experiments and numerical simulations and clarified that the efficiency of aggregate formation is dependent on the vibration-induced flow (VIF) field, particularly the frequency. These results suggest that our numerical simulation tool can help elucidate the mechanism of particle capture, which is crucial for agglutination-based NP detection.