Study on the co-luminescence effect of Tb-Gd-epinephrine system and its application to the sensitive determination of epinephrine at nanomol level

A new fluorimetric method for the determination of epinephrine is established by rare earth co-luminescence effect of Tb-Gd-E-Tris system. Under optimum conditions, a linear relationship has been obtained between the fluorescence intensity and the concentration of epinephrine in the range of 1.8 × 10⁻⁸ to 2.5 × 10⁻⁶ mol/l, and the detection limit is 4.5 × 10⁻⁹ mol/l (S/N = 3). The method is applied for the determination of epinephrine in injection and the recovery test in urine by standard addition method, and the results obtained are satisfactory. The mechanism of the co-luminescence in the system was also discussed.