Preparation of 2,4-dinitrophenylhydrazine-coated electrospun polymer fibers for determination of aldehydes in drinking water

Abstract

In this work, polymer fibers such as nylon6, polystyrene (PS) and polyacrylonitrile (PAN) were prepared by electrospinning process and coated with 2,4-dinitrophenythydrazine (DNPH) for derivatization, preconcentration and extraction of aldehydes in one step. Then, aldehydes-DNPH derivative were quantitatively analyzed b high-performance liquid chromatography DNPH with diameters of 100-200 nm. The optimum conditions for preparation of DNPH-coated electrospun polymer fibers were using 3 mL of 300 mg/L of DNPH in water-acetonitrile solution and coated at the rate of 100 µL/min. At this condition, the efficiencies of DNPH coating on all electrospun polymer fibers (nylon6, PS and PAN) were similar. Then, DNPH-coated electrospun polymer fibers were used for extraction of formaldehyde, acetaldehyde, propanal, butanal and hexanal in water. The highest extraction efficiency was achieved when 10 mL of aldehydes sample was loaded at 1 mL/min and desorbed with 100 µL of acetonitrile at the flow rate of 10 µL/min. Flectrospun nylon6 fibers provided higher extraction efficiency than electrospun PS and PAN fibers. The %recovery of aldehydes using DNPH-coated nylon6 fibers, DNPH-coated PS fibers and DNPH-coated PAN fibers were 43.9-96.3%, 30.5-76.5% and 16.2-63.8%, respectively. Therefore, only DNPH-coated nylon6 fibers were applied for the analysis of aldehydes in drinking water samples. No matrix interference was observed. %Recoveries of aldehydes at 10 µg/L spiked in drinking water were ranged from 42.3-83.8% which were satisfied for method accuracy.