Contactless manipulation of mixed phase fluids in liquid crystal polymer microtubes assisted with light-driven vortex

Abstract

AbstractSmart channels that manipulate liquid motion by anisotropic shape changes represent a promising candidate to construct microfluidics for biochemical analysis. However, the existing systems fail to provide a platform for solid exchange mediums to interact with multiple liquid phases, which is a universal technique to effectively extract, enrich, and precisely detect biomarkers. Herein, a combined photo/magnetic control strategy of mixed phase fluids, which integrates the contactless operations of suspending, depositing, and even separating, is reported for the first time based on a trilayer microtube consisting of a flexible supporting layer, photodeformable liquid crystal polymer, and hydrophilic blocking layer. The asymmetric photodeformation of the liquid crystal polymer generates an internal vortex in the microtube to homogenously disperse solid exchange mediums into various aqueous moving droplets and to enable efficient purification and enrichment of the target biomarkers. A newly constructed homemade portable protein analyzer guided by the combined photo/magnetic control strategy features the advantages of a short detection time (20 min), trace sample consumption (5 μL), and a low detection limit (1 μg mL−1).