title: Loading characteristics and chemical stability of headgroup-functionalized poly(ethylene glycol)-lipid ligand tethers on polypropylene capillary-channeled polymer fibers.
abstract: Polypropylene capillary-channeled polymer fibers have been modified by adsorption of headgroup-functionalized poly(ethylene glycol)-lipids to generate a species-specific stationary phase. In order to study ligand binding characteristics, a fluorescein-labeled poly(ethylene glycol)-lipid was used as a model system. Breakthrough curves and frontal analysis were employed to characterize the surface loading characteristics across a range of lipid concentrations and mobile phase flow rates. Efficient mass transfer and fluid transport yield a linear adsorption isotherm up to the maximum loading concentration of 3 mg/mL, at a linear velocity of 57.1 mm/s. Under these conditions, the dynamic binding capacity was found to be 1.52 mg/g of fiber support. Variation of the linear velocity from 8.6 to 57.1 mm/s showed only small changes in breakthrough volume. The maximum capacity of 1.8 mg/g is found under conditions of a load velocity of 34.2 mm/s and a concentration of 3 mg/mL lipid. Exposure of the lipid modified fibers to several challenge solvents reveals a chemically robust system, with only 50% acetonitrile and hexanes able to disrupt the lipid adsorption. The straightforward capillary-channeled polymer fiber surface modification with headgroup-functionalized lipids provides both a diverse yet practically robust ligand tethering system.
authors.affiliation: Department of Chemistry, Biosystems Research Complex, Clemson University, Clemson, SC, USA.
authors.forename: Abby J
authors.initials: AJ
authors.lastname: Schadock-Hewitt
authors.forename: R Kenneth
authors.initials: RK
authors.lastname: Marcus
mesh_terms: D002851:Chromatography, High Pressure Liquid; D008024:Ligands; D008055:Lipids / Q000737:chemistry*; D008968:Molecular Conformation; D011092:Polyethylene Glycols / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*
chemical_list: D008024:Ligands; D008055:Lipids; D011126:Polypropylenes; D011092:Polyethylene Glycols
keywords: Affinity chromatography; Capillary-channeled polymer; Fibers; Ligand loading; Poly(ethylene glycol)-lipids