Determination of norfloxacin using a terbium-sensitized electrogenerated chemiluminescence method

A simple electrogenerated chemiluminescence (ECL) analysis method for the determination of norfloxacin (NFLX) is reported. It is based on ECL produced by Na(2)SO(3), which is sensitized by the Tb-NFLX complex. The relative ECL intensity of the Tb(3+)-NFLX-Na(2)SO(3) system is proportional to the amount of NFLX. The optimized experimental conditions were investigated. The linear range and detection limit for NFLX were 1.0 x 10(-10)-8.0 x 10(-7) mol/L and 2.8 x 10(-11) mol/L, respectively. This method was successfully applied to the determination of NFLX in a capsule. NFLX in urine can be directly detected without pretreatment or separation.