(165e) Biodegradable Multilayered Nanofilms for Cell Isolation and Recovery

Li, W., Texas Tech University
Ahrens, C., Texas Tech University
Dong, Z., Texas Tech University
Selective isolation and purification of circulating tumor cells (CTCs) from whole blood is an important capability for both clinical medicine and biological research. Current techniques to perform this task place the isolated cells under excessive stresses that reduce cell viability, and potentially induce phenotype change, therefore losing valuable information about the isolated cells. The goal of our work is to effectively isolate as well as non-inversely recover cancer cells using a microfluidic device coated with a biodegradable multilayered nanofilm. To this end, we have applied layer-by-layer (LbL) assembly to create a library of ultrathin coatings using a broad range of materials through complementary interactions. We systematically studied the effect of various flow conditions and channel geometries on the thickness and surface roughness of the resulting films. We also investigated the biocompatibility and degradation behaviors of a series of enzymatically-degradable films made from naturally derived polymers. By developing an LbL nano-film coating with an affinity-based cell-capture surface that is capable of selectively isolating cancer cells from whole blood, and that can be rapidly degraded on command, we are able to gently isolate cancer cells and recover them without compromising cell viability or proliferative potential. This film system has been applied to two capture and release platforms: 1) microfluidic HB chip and 2) hollow glass microspheres. Detailed characterization on the film system was conducted via fluorescent microscopy, AFM, profilometer, TGA, QCM-D, immunofluorescent staining, etc. Our approach has the capability to overcome practical hurdles and provide viable cancer cells for downstream analyses.