Simultaneous determination of Br^- and I^- with a multiple fiber-optic fluorescence sensor

A dual fiber-optic sensor for the simultaneous determination of bromide and iodide is successfully demonstrated. The device is based upon the dependence of quenching effects on individual fluorophores (quinine and harmane) and quenchers (bromide and iodide). From the point of view of practical application, n unknown analyte species should be able to be determined with a sensor array which contains n sensor elements on which n fluorophores are immobilized. The relative error of the new sensors for the determination of bromide and iodide is less than 5%. The sensor combination is reversible and exhibits an overall response time of 2 minutes. The interference of several ions on the sensors has been studied.