Determination of ampicillin by flow-injection electrochemiluminescence based on its sensitive effection

It was found that the weak electrochemiluminescence (ECL) signal from the electrochemical oxdization of luminol was greatly enhanced by the ampicillin. Based on this observation, a new and sensitive ECL method for the determination of ampicillin was proposed. The experimental conditions affected the ECL intensity were investigated and optimized. Under the optimum conditions, the ECL response is linear in the range of 8.0×10~(-8)～5.0×10~(-5) g/mL ampicillin with a detection limit of 5.0×10~(-8) g/mL. The relative standard deviation is 2.0%. This method was used to determine ampicillin in samples with satisfactory results.