Four crown ether derivatives of o-phenanthroline were synthesized and used as neutral carriers for preparing poly(vinyl chloride) (PVC) membrane electrodes sensing primary amine species. The potentiometric response characteristics of the electrodes prepared were investigated. The effect of experimental parameters on the electrode performance was studied. The membrane composition was optimized by using orthogonal polynomial regression. The electrode sensitive to benzyl amine as a model analyte showed a linear response range of 1.0 ?10-5 to 0.1 mol/L with a detection limit of 2.0 ?10-6 mol/L and a slope of 55.6 mV/decade. The linear potentiometric response of the mexiletine-sensitive electrode was 6.0 ?10-6 to 0.1 mol/L, and the detection limit was 8.0 ?10-7 mol/L with a slope of 58.0 mV/decade. The transfer behavior of amines and ammonium ions through an organic phase was investigated by means of the bulk liquid membrane transport experiment

Key words: CROWN ETHER COMPOUNDS, ION SELECTIVE ELECTRODE, PHENANTHROLINE, PRIMARY AMINE