A siloxane-functionalized calixpyrrole derivative was synthesized starting from the corresponding alcohol-functionalized calixpyrrole. Structural elucidation was carried out by using NMR spectroscopy, mass spectrometry and X-ray diffraction analysis. The use of this siloxane-functionalized calixpyrrole for modification of various silica solid supports (silica gel 60, fume silica, and SiO(2) nanopowder) was studied. Characterization of the modified silica solid supports was achieved by FTIR, TGA, and elemental analysis. It was also shown that the production of silica nanoparticles is possible via a sol-gel reaction of siloxane-functionalized calixpyrrole and tetraethoxysilane (TEOS). Calixpyrrole modified silica solid supports were found to sense chloride anions of Azure A dye. (C) 2011 Elsevier Ltd. All rights reserved.