(395q) Synthesis of Titanosilicate Nanoparticles for Specific Adsorption of Biomolecules

Many examples can be found in the literature of either porous surfactant-templated titanosilicates or nonporous non-imprinted core-shell titanosilicate nanoparticles. In this work, we propose to use sugar-based surfactants able to enter into complexes with titanium precursors to develop a method of synthesizing nonporous silica particles coated with imprinted titanium sites for adsorption of specific sugars.

The particles are prepared through a modification in the Stöber synthesis method for silica nanoparticles.  Titania precursors complexed with specific saccharide surfactants are introduced to this method to provide surface functionalization and imprinting.  It is hypothesized that addition of complexed sugar surfactant-bound titania along with cetytrimethylammonium bromide during early stages of the Stöber particle synthesis will lead to the creation of specific titanium-based adsorption sites on the surface of the particles.  The titanium not only introduces the possibility of greater functionality and specificity of interactions with saccharides than silica alone, but also the possibility that non-specific binding sites on the silica surface can be blocked using silane chemistry with protection at the titanium site by the sugar template itself or other functional groups. Characterization of particles will be done using a combination of techniques including scanning electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering, transmission electron microscopy and nitrogen adsorption.

Adsorption experiments based on depletion of biological molecules from solution will be utilized to understand the specificity and selectivity of the titania-containing particles in comparison to silica along or particles prepared without surfactant imprinting.  In particular, the ability of the particles to display enhanced binding to target saccharides (e.g. D-glucose vs. D-xylose) when imprinted using a surfactant with the same sugar headgroup (e.g. n-octyl-beta-D-glucopyranoside) will be discussed.  Preparation of such imprinted titanosilicate particles is of potential importance for creating highly selective particles for separation of target saccharides and other biomolecules from mixtures of similar compounds.