Date of Award
Bachelor of Science
A general approach for the development of an analytical method for the detection of specific cations using flow injection analysis has been investigated. In this approach, an ionophore (I), which is selective for the cation (M+) of interest, is noncovalently immobilized on a controlled pore glass (CPG) surface. A column of tygon tubing is then filled with the 1-CPG phase and placed in the cell compartment of a spectrofluorometer. When an aqueous mobile phase containing M+ and 8-anilino+naphthalene sulfonic acid (ANS) is pumped through the column, the M+ reversibly binds to the immobilized I, and the resulting complex then forms an ion-pair on the CPG surface with the negatively charged ANS. The ANS fluorescence signal, which is highly quenched in aqueous solution, increases dramatically for the ANS bound to the hydrophobic CPG surface and this signal can be used to determine the amount of M+ originally in the mobile phase. Selectivities and detection limits for a number of M+ / I combinations, including K+ / dibenzo-18-crown-6, K+ / valinomycin, Na+ / sodium ionophore II, K+ / kryptofix, and NH4+ / nonactin, have been studied.
Cummings, John G., "Development of an analytical method for the detection of specific cations using flow injection analysis" (1988). Honors Theses. 2016.