Flow injection chemiluminescence determination of epinephrine using epinephrine-imprinted polymer as recognition material

A flow injection chemiluminescence (CL) method using epinephrine-imprinted polymer as recognition material was investigated for the determination of epinephrine. The analyte, epinephrine, was selectively and temporarily adsorbed on the epinephrine-imprinted polymer, which was packed into a flow-cell placed in front of the window of a photomultiplier tube. Afterwards, the CL reagent, the emerging stream of luminol (presence of potassium ferrocyanide) and potassium ferricyanide flowed through the flow-cell and reacted with epinephrine adsorbed on the polymer to produce strong CL. The CL intensity responded linearly to the logarithm of the concentration of epinephrine within 5.0×10⁻⁹ to 1.0×10⁻⁷ mol/l range with a detection limit of 3×10⁻⁹ mol/l. The R.S.D. for 2.0×10⁻⁸ mol/l of epinephrine solution was less than 5% (n=7). Interference experiments demonstrated that the application of molecular imprinted polymer (MIP) to CL analysis could be improved the selectivity of the method greatly. Tests of the recovery for known amount of epinephrine in serum were carried out and satisfactory results were obtained. At the same time, the binding characteristic of the polymer to epinephrine was evaluated by the batch method and the dynamic method.