M.W. Frey, E. Gonzalez, L. Shepherd
Keywords: biotin, avidin, poly(lactic acid) PLA, poly(lactic acid)-block-poly(ethylene glycol) (PLA-b-PEG), electrospinning, functional nanofibers
Summary:Biotin surface functionalized hydrophilic non-water-soluble biocompatible poly(lactic acid) (PLA) nanofibers are created for their potential use as biosensors. Biotin concentration, biotin addition method and poly(lactic acid)-block-poly(ethylene glycol) (PLA-b-PEG) block copolymer addition were studied to optimize nanofiber hydrophilicity, biotin availability and stability of the nanofibers over time and during water immersion. Morphology and surface-available biotin of the final fibers were studied by Field Emission Scanning Electron Microscopy (FESEM) and competitive colorimetric assays. The incorporation of PLA-b-PEG block copolymers not only decreased fiber diameters but also dramatically increased the amount of biotin available at the fiber surface able to bind avidin. When biotin was incorporated freely, overall addition could be maximized, however, biotin leached from the fibers into water. By grafting biotin to the block co-polymer as PLA-b-PEG-biotin hydrophiicity, biotin surface availabitity and stability of the fibers in water. The functional hydrophilic nanofibers created in this work shows a potential application as a component of biosensors for point-of-care diagnostics.