Preparation, Characterisation and Modification of Ammonium Tartrate Templated Organosilicate Nanotubes

ABSTRACT

Silica nanotubes have been prepared by room temperature sol-gel chemistry, using crystalline ammonium tartrate as the tube-forming template. In this study, hybrid organosilicates have been prepared by incorporating methyltriethoxysilane (MTES), polydimethylsiloxane (PDMS) and 3-aminopropyl triethoxysilane (APTES) precursors during sol formation. The synthetic conditions have been systematically studied and a range of hybrid organosilicate tubes prepared. The physical characteristics of the materials were examined by scanning electron microscopy (SEM) and the aging of the tubes due to slow post-gelation condensation reactions was investigated. The morphology of the nanotubes changes when organosiloxanes are incorporated as precursors. Two methods of labeling the nanotubes, fluorescein labeled tubes and rhodamine B-dextran encapsulated in silica nanotubes, were demonstrated. The adsorption of enzyme proteins on nanotube walls is readily observed by SEM.

Keywords:

• ammonium tartrate
• hybrid organosilicates
• scanning electron microscopy
• silica nanotubes
• sol-gel chemistry