The transport characteristics of a shear-thinning fluid driven by metachronal magnetic artificial cilia

• We studied the transport of shear-thinning fluids driven by a magnetic artificial cilia array that moves in a metachronal motion in a microfluidic environment. • Shear thinning fluids exhibit higher flow rate than the Newtonian fluid with a matching zero-shear viscosity, especially at higher frequencies. • The reason for higher flow rate is the increase in cilia stroke in low viscosity zones that are in turn created by cilia motion. • The transport effectiveness is impacted by cilia spacing, but to a smaller extent in shear thinning fluids than that in Newtonian fluids. • This work provides new insights for using artificial cilia in handling non-Newtonian fluids, with implications for biomedical, chemical, and organ-on-a-chip applications. Precise and localized fluid control at small scales is essential for advancing lab-on-a-chip and organ-on-a-chip technologies in fields like biomedicine, drug discovery, and chemical analysis. Traditional pumps are often inadequate for efficient small-volume transport in microfluidic environments, making artificial cilia an appealing solution for integrated, localized fluid management. While magnetically driven cilia offer a biocompatible, non-invasive approach, existing research has primarily focused on Newtonian fluids, leaving the behaviour of shear-thinning fluids largely unexplored. This study investigates the transport characteristics of shear-thinning fluids using a magnetic cilia array under a rotating magnetic field, generating metachronal motion that modulates local viscosity. Results show that the dynamic coupling between cilia beating and the shear‑thinning fluid produces transport behaviour different from that in a Newtonian fluid, particularly at high driving frequencies, offering insights that can inform future design and optimization of magnetic cilia systems for precise fluid control in microfluidic applications, as well as highlighting the importance in studying cilia driven flow in non-Newtonian fluids.