The use of 3-(2-pyridyl)-5, 6-diphenyl-1, 2, 4-triazine as precolumn derivatizing reagent in HPLC determination for Fe(II) in natural samples

The 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT) was used for the first time as a precolumn derivatizing reagent applied in the high-performance liquid chromatography (HPLC) method with UV-detection for the Fe (II) determination. The Fe (II) reacts with PDT to form a magenta colored chelate in the presence of sodium dodecyl sulfate (SDS) and acetic acid-sodium acetate buffer solution medium of pH 4.65. The selection of maximum absorbance detect wavelength and the optimum composition of the organic modifier in the mobile phase were investigated in detail for the quantitative determination of Fe (II) using HPLC system. The formed Fe(II)-PDT chelate was satisfactorily separated from PDT on a Agilent Shim-pack ODS column (Eclipse XDB-C8,4.6x150mm) by isocratic elution with acetonitrile and 0.02 mol L-1 acetic acid-sodium acetate buffer solution (pH 4.65, containing 0.02% of SDS and 60x10-3 mol L-1 NaClO4) as mobile phase at a flow rate of 1 mL min-1, and monitored with a multiple wavelength detector. The detection limit (S/N =3) is 0.35 ng ml-1. Due to the excellent separation ability of HPLC, the innovative introduction of PDT as the precolumn derivatizing reagent, and the proper selection of the detect wavelength, the sensitivity of our newly developed HPLC method was enhanced remarkably compared to the common spectrophotometric methods. The developed HPLC method was successfully applied to the determination of Fe(II) in lake water samples