Wirelessly Actuated Ciliary Airway Stent for Excessive Mucus Transportation

Abstract

Small‐scale cilia‐like devices that can manipulate fluids in narrow spaces have great potential in microfluidics, biomechanics, biomedical engineering, and other applications. However, prior studies mostly focus on artificial cilia for pumping fluids in lab‐on‐a‐chip microfluidic applications. The design and control of artificial cilia for transporting viscous mucus in confined and tubular structures remain challenging and medical devices such as airway stents with ciliary function are still missing. Herein, a method is reported that enables integrating artificial cilia arrays on 3D curved surfaces and an airway ciliary stent is presented for excessive mucus transportation. The method allows encoding bioinspired non‐reciprocal motion and metachronal waves for efficient fluid pumping in tubular structures. The method also introduces a lubricant hydrogel coating layer on artificial cilia inspired by the periciliary layer in airway cilia, which further enhances viscous fluid transportation. It is demonstrated that a novel ciliary airway stent can transport viscous porcine mucus in a lung phantom even faster than the respiratory cilia in a healthy human lung. The methods of designing, integrating, and controlling artificial cilia on 3D curved surfaces thus enable the unprecedented function of removing excessive mucus beyond traditional airway stents for treating various lung diseases in a minimally invasive manner.

Bio-Inspired Magnetically Responsive Silicone Cilia: Fabrication Strategy and Interaction with Biological Mucus

“…Further studies using a controlled magnetic field activation need to be performed to optimize the cilia motion conditions and generate an effective fluid flow [ 40 ]. Moreover, it was recently demonstrated that the presence of a hydrophilic lubricant layer within a ciliary array accelerates the transportation of viscous fluids, including porcine mucin, and thus, can be an interesting strategy to enhance mucociliary clearance in ciliated stents [ 41 ]. It is worth noting that the mucus deposition on the substrate can accelerate its dehydration and hinder its displacement through the coughing mechanism.…”

“…porcine mucin, and thus, can be an interesting strategy to enhance mucociliary clearance in ciliated stents [41]. It is worth noting that the mucus deposition on the substrate can accelerate its dehydration and hinder its displacement through the coughing mechanism.…”

Directional Pumpless Transport of Biomolecules through Self-Propelled Nanodroplets on Patterned Heterostructures

“…Directional transport of biological molecules in interstitial fluid flow via pressure-driven or self-propelled motion is of critical importance for living organisms. Inspired by natural biomolecular motions, artificial cilia systems and biomolecular-motor-based systems have been developed to achieve micrometer- or nanoscale transport of biomolecules, offering promising applications in bioseparations, biosensing, and biomedical drug delivery. − Specifically, the transport of biomolecules such as DNA and peptides in microfluidic/nanofluidic networks has attracted considerable attention in the novel lab-on-a-chip bioanalysis technology. − Stein et al studied the pressure-driven mobility and dispersion of DNA molecules in microfluidic and nanofluidic channels, which reflected the statistical properties of DNA polymer coils. Menard and Ramsey investigated the dynamic nature of the electrophoretically driven transport of double-stranded DNA through focused ion beam milled nanochannels.…”