This study is related to the determination of fluoride ion by the conversion of pink-colored Fe(III) and indole3-acetic acid (IAA) into a colorless hexafluoride ferrite complex with the addition of fluoride. The optimum conditions of the complex formation were found to be pH and a temperature of 60 °C. The maximum absorption wavelength of the complex and the detection limit of the method were 525 nm and mg/L, respectively. The interfering effects of the different cations (Ag+, Al3+, Ba2+, Ca2+, Cd2+, Co2+, Cu2+, K+, Mg2+, Na+, Ni2+, Pb2+) and anions (SO2−4, SO2−3, NO−2, I−, Br−, Cl−, SCN−, CH3COO− , H2PO−4, ClO−4) were also investigated. |