A Simple and Sensitive Fluorescence Quenching Method for the Determination of Trace IO<sub>3</sub><sup>-</sup> Using Acridine Red

Abstract

In the medium of HCl containing KI, acridine red (AR) exhibited a fluorescence peak at 550 nm, and acridine ornage (AO) has a fluorescence peak at 520 nm. Upon addition of IO3-, it reacts with excessive I-to form I3-. The AR and I3-combine to form an association particle that caused fluorescence quenching at 550 nm. IO3-concentration in the range of 5.0-120×10-7mol/L can be determined by AR fluorescence quenching method.