title: Parallel, open-channel lateral flow (immuno) assay substrate based on capillary-channeled polymer films.
abstract: Presented here is a novel implementation of polypropylene capillary-channeled polymer (C-CP) films, functionalized for bioaffinity separations and implemented as a platform for lateral flow (immuno) assays. The parallel ∼80 μm × 80 μm channels pass test solutions down the 30 mm film length via spontaneous wicking action, setting up the possibility for immobilizing different capture agents in the respective channels. The base-film modification process is divided into two steps: ultraviolet light treatment to improve hydrophillicity of the polypropylene substrate and the physical adsorption of a functionalized lipid tethered ligand (LTL) as a selective capture agent. The entire modification procedure is performed under ambient conditions in an aqueous solution without extreme pH conditions. In this demonstration, physical adsorption of a biotinylated-LTL onto the UV-treated PP surface selectively captures Texas Red-labeled streptavidin (SAv-TR) in the presence of enhanced green fluorescence protein (EGFP), which passes without retention in less than 5 s. In addition to the fluorescence imaging of the protein solutes, matrix assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to confirm the formation of the LTL-SAv conjugates on the channel surface as well as to demonstrate an alternative means of probing the capture step. The present effort sets the groundwork for further development of C-CP films as a parallel, multi-analyte LFA platform; a format that to-date has not been described.
authors.affiliation: Department of Chemistry, Clemson University, Clemson, South Carolina 29634, USA. marcusr@clemson.edu.
authors.forename: Lynn X
authors.initials: LX
authors.lastname: Zhang
authors.forename: Liuwei
authors.initials: L
authors.lastname: Jiang
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Willett
authors.forename: R Kenneth
authors.initials: RK
authors.lastname: Marcus
mesh_terms: D000327:Adsorption; D001710:Biotin / Q000031:analogs & derivatives / Q000737:chemistry; D049452:Green Fluorescent Proteins / Q000737:chemistry; D008024:Ligands; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D010100:Oxygen / Q000737:chemistry; D011126:Polypropylenes / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D019809:Streptavidin / Q000032:analysis* / Q000737:chemistry; D014466:Ultraviolet Rays; D014966:Xanthenes / Q000737:chemistry
chemical_list: D008024:Ligands; D011126:Polypropylenes; D014966:Xanthenes; D049452:Green Fluorescent Proteins; D001710:Biotin; C034657:Texas red; D019809:Streptavidin; D010100:Oxygen