Stability of layered aluminum and magnesium organosilicates

New nanostructered layered inorganic–organic aluminum (Sil–Al) and magnesium (Sil–Mg) organosilicates – were prepared by a single step template sol–gel route under mild conditions, using a new alkoxysilane [(3-urea-dodecyl)propyl]triethoxysilane, containing embedded polar urea groups. The hybrids were characterized by elemental analysis, infrared spectroscopy, solid-state 29Si, 13C and 27Al nuclear magnetic resonance and X-ray diffraction. The XRD data showed that the magnesium hybrid material exhibits a lamellar structure similar to talc, a natural inorganic silicate. In order to employ these alternative sorbent materials for solid phase extraction applications, the chemical stability of the hybrids were investigated over a wide pH range varying from 2 to 12.