Abstract: The present invention relates to porous substrate compositions and methods for producing such compositions. In one embodiment, the porous substrate composition of the present invention comprises sintered spherical particles of a substantially uniform size. The porous media compositions of the present invention comprise relatively randomly-ordered particles with a void fraction significantly higher than compositions with a more ordered, close-packed configuration. The present invention further relates to composite porous media compositions comprising two or more relatively discrete layers of sintered particles.

Abstract: The present invention relates to porous substrate compositions and methods for producing such compositions. In one embodiment, the porous substrate composition of the present invention comprises sintered spherical particles of a substantially uniform size. The porous media compositions of the present invention comprise relatively randomly-ordered particles with a void fraction significantly higher than compositions with a more ordered, close-packed configuration. The present invention further relates to composite porous media compositions comprising two or more relatively discrete layers of sintered particles.

Abstract: A process for preparing nanoparticle coated surfaces including the steps of electrostatically coating surfaces with polyelectrolyte by exposing the surface to a solution or suspension of polyelectrolyte, removing excess non-bound polyelectrolyte, then further coating the particles with a multi-layer of charged nanoparticles by exposing the polyelectrolyte-coated surface to a fluid dispersion including the charged nanoparticles. The process steps can optionally be repeated thereby adding further layers of polyelectrolyte followed by nanoparticles as many times as desired to produce a second and subsequent layers. The polyelectrolyte has an opposite surface charge to the charged nanoparticles and a molecular weight at the ionic strength of the fluid that is effective so that the first, second, and subsequent layers independently comprise a multiplicity of nanoparticle layers that are thicker than monolayers.

Abstract: A process for preparing nanoparticle coated surfaces including the steps of electrostatically coating surfaces with polyelectrolyte by exposing the surface to a solution or suspension of polyelectrolyte, removing excess non-bound polyelectrolyte, then further coating the particles with a multi-layer of charged nanoparticles by exposing the polyelectrolyte-coated surface to a fluid dispersion including the charged nanoparticles. The process steps can optionally be repeated thereby adding further layers of polyelectrolyte followed by nanoparticles as many times as desired to produce a second and subsequent layers. The polyelectrolyte has an opposite surface charge to the charged nanoparticles and a molecular weight at the ionic strength of the fluid that is effective so that the first, second, and subsequent layers independently comprise a multiplicity of nanoparticle layers that are thicker than monolayers.

Abstract: The present invention relates to microparticles, particularly spherical silica microparticles, which may be useful in liquid chromatography. Specifically, the microparticles include a solid core and an outer porous shell surrounding and irreversibly joined to the core. The shell is composed of a plurality of colloidal nanoparticles, which are applied using an electrostatic multi-multilayering method. The resulting microparticles have a small particle diameter, such as about 1 ?m to 3.5 ?m, a high particle density, such as about 1.2 g/cc to 1.9 g/cc, and a high surface area, such as about 50 m2/g to 165 m2/g. These microparticles can be used to form packed beds and liquid chromatographic columns, which are more efficient and rugged than conventional liquid chromatographic columns.

Abstract: Highly purified, porous silica microspheres contain functional groups which are capable of selectively binding to reaction impurities, such as excess reactant or reaction by-products, which are contained in a reaction medium. The reaction impurities can thereby be efficiently removed from the reaction medium, providing a convenient method for product purification.

Abstract: Highly purified, porous silica microspheres contain functional groups which are capable of selectively binding to reaction impurities, such as excess reactant or reaction by-products, which are contained in a reaction medium. The reaction impurities can thereby be efficiently removed from the reaction medium, providing a convenient method for product purification.

Abstract: Highly purified, porous silica microspheres contain functional groups which are capable of selectively binding to reaction impurities, such as excess reactant or reaction by-products, which are contained in a reaction medium. The reaction impurities can thereby be efficiently removed from the reaction medium, providing a convenient method for product purification.

Abstract: Highly purified, porous silica microspheres contain functional groups which are capable of selectively binding to reaction impurities, such as excess reactant or reaction by-products, which are contained in a reaction medium. The reaction impurities can thereby be efficiently removed from the reaction medium, providing a convenient method for product purification.

Abstract: Highly purified, porous silica microspheres contain functional groups which are capable of selectively binding to reaction impurities, such as excess reactant or reaction by-products, which are contained in a reaction medium. The reaction impurities can thereby be efficiently removed from the reaction medium, providing a convenient method for product purification.