| This thesis describes the development and characterization of a series of fibre-optic probes, incorporating a number of three-coordinate organoboron luminescent compounds, for the detection of environmentally relevant analytes. Two different classes of compounds were studied; the first contained compounds functionalized by the (1-naphthyl)phenylamino group and the second class contained compounds functionalized by either the 7-azaindolyl or 2,2'-dipyridylamino functional groups. Linear compounds, starburst compounds and coordination complexes were compared based on their sensitivity for particular analytes.;Fluorescence measurements revealed that probes made of linear compounds, such as p-(1-naphthylphenylamino)-4,4'-biphenyldimesitylborane (BNPB), were most sensitive to chlorobenzene. Probes made of linear compounds were also selective for chlorobenzene. The coordination complex probes, incorporating the 7-azaindolyl or 2,2'dipyridylamino functional groups, were more sensitive to all analytes in comparison to their non-coordinated counterparts. It was determined that all of the probes made of starburst compounds showed poor sensitivity for all analytes. It was determined that BNPB and the p-(2,2'-dipyridylamino)biphenyldimesitylborane-Zn(O2CCF 3)2 (1·Zn) probes retained their selectivity to chlorobenzene after extended storage.;An approach for determining the binding constant information for these probes was determined and performed for probes producing stable responses over extended periods of time. The binding constant, K, reveals the strength of binding between the compound in the bead and the analyte. For the BNPB probe, K for chlorobenzene is larger than K for chloroform.;Since probes made of coordination complexes were more sensitive to all analytes in comparison to their non-coordinate counterparts, a zinc coordination compound was made using the starburst compound tris[p-(2,2'-dipyridylamino)phenylduryl]borane as the ligand. A full characterization of its fluorescence response was not completed due to the degradation of the compound.;Solutions of luminescent compounds were mixed with polydimethylsiloxane to form modified beads, which were attached to fused silica optical fibres. A miniature instrument was assembled using an LED light source and a CCD spectrometer. The use of embedded fluorescent compounds provides detection of non-fluorescent analytes, based on complexation with the analytes which changes the fluorescence emission. A modified version of the Stern-Volmer equation was used to characterize the fluorescence response. |
