Abstract

Because of their availability in discrete sizes and the relative ease with which they can be derivatized and characterized, polymeric nanoparticles have become important model surfaces in bioanalytical work. One finds that increased reaction rates and reduced steric hindrance are the results when proteins or other reactive macromolecules are attached to ever smaller particulate carriers in the sub-micron size range. The introduction of new chemical features to a surface can be followed and optimized through work with polymeric surfactants that adsorb in a stable manner to hydrophobic surfaces, such as those associated with the latex particles. By introducing reactive structures into the endgroups of such polymeric surfactants, and then mixing derivatized with underivatized product prior to adsorption, one can let the process yield surfaces with pre-determined levels of functionalization. By mixing surfactants with different types of reactive structures it is possible to engineer surfaces with distinctly optimal performance in specific situations. One such situation is the attachment of the particle to some other substrate, e.g. a flat surface for optical read-out. Such attachments have been performed and the bound particles have proven to resist shear-induced removal even at high rates of laminar flow. Through this strategy, particles attached in large arrays may be relied upon to facilitate the complex analyses mandated by the rapidly growing field of proteomics.

Keywords: steric stabilization, poly(ethyleneglycol) (peo), sedimentation field-flow fractionation (sedfff), photon correlation spectroscopy, total internal reflectance (tir) microscopy, surfactant, pluronic f shield, antibodies, bioreactors, protein attachment