6533b851fe1ef96bd12a8f27

RESEARCH PRODUCT

Modular approach toward bioactive fiber meshes carrying oligosaccharides

subject

description

A modular strategy toward (bio)functional nanofiber meshes by electrospinning is described. In contrast to commonly established, multistep protocols or complex spinning setups, a straightforward single-step procedure is investigated to obtain polymer nanofibers with pentafluorophenyl (Pfp)-activated esters on the surface. The aim was to electrospin, for the first time, poly(pentafluorophenyl methacrylate) (PPfpMA) and PPfpMA/poly(epsilon-caprolactone) (PCL) blends, resulting in reactive nanofibers with fiber surfaces that can be functionalized with suitable bioactive entities. While PPfpMA fibers are brittle the spinning of PCL/PPfpMA blends leads to improved mechanical stability of the obtained fabrics. The effective introduction of surface functionalities onto the fibers was proven by both model compounds and bioactive monosaccharides. The Pfp-activated esters are enriched at the fiber surfaces and react cleanly with nucleophiles such as 2-aminoethanol, aminofluorescein, or amino-functionalized monosaccharides to generate a robust amide anchor. The attachment of functional entities releases a Pfp group that allows for monitoring of the functionalization reaction with UV/vis spectroscopy. X-ray photoelectron spectroscopy (XPS) and contact angle measurements indicate effective introduction of functionalities to the fiber surfaces, and fluorescence microscopy suggests a homogeneous distribution of amino functional fluorescence markers on the meshes. The bioavailability of the introduced carbohydrates is shown by macrophage stimulation experiments using PCL/PPfpMA fiber meshes, which are functionalized with 2-aminoethyl-alpha-d-mannopyranoside or beta-d-galactopyranoside. Meshes functionalized with mannose specifically enhance the cytokine production of macrophages when costimulated with lipopolysaccharides compared to galactose- or aminoethanol-functionalized PCL/PPfpMA fiber mat controls.