Abstract:
Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università di Napoli Federico II, Naples, Italy
Manipulation of particles suspended in fluids flowing in microfluidic channels is required in a variety of biological, diagnostic and therapeutic applications. For instance, alignment of particles into a tight stream is a necessary step prior to their counting, detecting, and sorting. Generally, this task is accomplished by using water as suspending medium and by properly fabricating a complex device aimed to displace particle trajectories.
In the last years, our group has exploited viscoelasticity of the suspending liquid as a key ingredient to develop microfluidic applications. Indeed, the viscoelastic nature of polymer solutions leads to an internal force acting on the suspended particles. Such force can, for instance, promote particle migration, which in turn can be exploited to manipulate the trajectories of suspended particles in very simple devices.
Rheological properties of the suspending liquid play then a crucial role in such rheo-engineered microfluidic applications. In this work, we present some results on experiments and simulations on viscoelasticity-induced particle alignment of spherical and non-spherical particles, and on the possibility to form equally-spaced particle trains.