Headspace solid-phase microextraction sampling of endogenous aldehydes in biological fluids using a magnetic metal-organic framework/polyaniline nanocomposite.

Nano-porosity, crystal structure, good thermal and mechanical stability, high surface-to-volume ratio, nanoscale cavities, and uniform pore topology have made metal-organic frameworks (MOFs) one of the best class of sorbents for adsorption/separation purposes. In this research, a metal-organic framework/polyaniline magnetite nanocomposite was synthesized and intercalated by polyaniline by electrophoretic deposition on the surface of a thin steel wire, to prepare a solid-phase microextraction fiber. It was coupled with gas chromatography-flame ionization detection and employed for the extraction and determination of aldehydes in biological samples. The magnetic nanocomposite was characterized using scanning electron microscopy, energy dispersive x-ray analysis, and Fourier transform infrared spectroscopy techniques. Under the optimal experimental conditions, the calibration curves were linear in the range of 0.01-1 and 0.1-1 μg/L for hexanal and heptanal, respectively. The limits of detections for hexanal and heptanal were 0.001 and 0.01 μg/L, respectively. Intra-fiber repeatability for six replicate analyses of 0.2 μg/L of the analytes was over the range 3.5-7.1%. Inter-fiber (fiber-to-fiber) reproducibility, calculated by six replicate analyses of the same concertation using three different fiber, was found to be 10.4-15.7%. The developed procedure was successfully utilized for the analysis of hexanal and heptanal in human plasma and urine samples. This article is protected by copyright. All rights reserved.