Immobilization of fluorescent chemosensor on pyrogenic silica: a promising device for gaseous detection.

A new approach to enhance performances of a cyclodextrin-based fluorescent chemosensor combining grafting on a silica matrix and quaternization reaction is presented. The full characterization of new fluorescent hybrid material has clearly revealed the embedding of cyclodextrin inside the siliceous material. Finally, through a comparison with previous aqueous studies, a preliminary test of toluene detection was presented and highlighted the high potential of this approach, which opens attractive perspectives of evolution toward more sensitive and selective VOC's sensing in air or in hot industrial gaseous waste.

A new sensitive organic/inorganic hybrid material based on titanium oxide for the potentiometric detection of iron(III).

The formation of a new hybrid material based on titanium dioxide as inorganic support and containing an iron organochelator (ICL670) is described. An organophosphorous coupling agent was used to graft the organic molecule on the oxide surface. The attachment of the organic substrate was well-confirmed by FTIR (DRIFT), solid-state (31)P and (13)C CPMAS NMR, thermal analysis and the integrity of the structural and morphological parameters were verified using XRD and TEM analyses. The interaction between the material and dissolved iron(III) was also investigated through potentiometric measurements and demonstrated the interest of this new non-siliceous based hybrid material. The obtained linear evolution of the open circuit potential from 10(-2) to 10(-6) mol L(-1) can be used for the analytical detection of iron(III).

Rapid synthesis of a versatile organic/inorganic hybrid material based on pyrogenic silica.

An efficient approach has been developed to synthesize a new versatile organo-silica material by non-conventional method (microwave irradiation and ultrasonic vibration) from amorphous pyrogenic silica and has been compared with thermic procedure. The samples were fully characterized by FTIR, solid-state (29)Si and (13)C CP/MAS NMR, thermogravimetric analysis (TGA), elemental analysis, scanning electron microscopy (SEM) and by N(2)-sorption isotherms measurements. The functionalization of silicon dioxide by 4-(chloromethylphenyl) trichlorosilane has been easily achieved by ultrasound irradiation in a very short time with high loading of organic fragments. Significant different sizes of pores were observed according to conventional or non-conventional synthesis procedure. In addition, new structural properties have been created with the emergence of a mesoporosity.