HPLC Determination of Formaldehyde in Flour Samples using 2,4,6-Trichlorophenyl Hydrazine as Derivatization Reagent

Abstract

A new simple and sensitive high-performance liquid chromatography (HPLC) method for the determination of formaldehyde in flour samples has been developed. Formaldehyde was quantified after derivatization with a readily available reagent, 2,4,6-trichlorophenyl hydrazine (TCPH) under basic conditions. The formaldehyde-TCPH derivative was eluted with chromatographic mobile phase of 70:30 (v/v) acetonitrile:water at a flow rate of 1.0 mL min–1; wavelength, 222 nm; injection volume, 50 μL, using a C18 ODS Hypersil column (250 mm × 4.5 mm, 5 μm). The calibration curve was linear over the range of 0.001-10 μg mL-1 with R2 = 0.999. Recoveries at three different concentration levels (0.1, 1.0 and 5 μg mL-1) ranged from 92.0-101.7% with RSD less than of 2.2%. The limit of detection (LOD) and limit of quantification (LOQ) were 0.3 and 1.0 ng mL-1, respectively. The developed method was used for the determination of formaldehyde in various flour-based samples.