Electrospun nitrocellulose and nylon: Design and fabrication of novel high performance platforms for protein blotting applications

BACKGROUND Electrospinning is a non-mechanical processing strategy that can be used to process a variety of native and synthetic polymers into highly porous materials composed of nano-scale to micron-scale diameter fibers. By nature, electrospun materials exhibit an extensive surface area and highly interconnected pore spaces. In this study we adopted a biological engineering approach to ask how the specific unique advantages of the electrospinning process might be exploited to produce a new class of research/diagnostic tools. METHODS The electrospinning properties of nitrocellulose, charged nylon and blends of these materials are characterized. RESULTS Nitrocellulose electrospun from a starting concentration of < 110 mg/ml acetone deposited as 4-8 mum diameter beads; at 110 mg/ml-to-140 mg/ml starting concentrations, this polymer deposited as 100-4000 nm diameter fibers. Nylon formed fibers when electrospun from 60-140 mg/ml HFIP, fibers ranged from 120 nm-6000 nm in diameter. Electrospun nitrocellulose exhibited superior protein retention and increased sensitivity in slot blot experiments with respect to the parent nitrocellulose material. Western immunoblot experiments using fibronectin as a model protein demonstrated that electrospun nylon exhibits increased protein binding and increased dynamic range in the chemiluminescence detection of antigens than sheets of the parent starting material. Composites of electrospun nitrocellulose and electrospun nylon exhibit high protein binding activity and provide increased sensitivity for the immuno-detection of antigens. CONCLUSION The flexibility afforded by electrospinning process makes it possible to tailor blotting membranes to specific applications. Electrospinning has a variety of potential applications in the clinical diagnostic field of use.