In situ electrosynthesis of a copper-based metal-organic framework as nanosorbent for headspace solid-phase...

For the first time, a fiber coating based on copper metal-organic framework was fabricated on an anodized stainless steel wire by an in situ electrosynthesis approach. The fiber was used for the preconcentration and determination of methamphetamine by headspace solid-phase microextraction followed by gas chromatography-flame ionization detection. The electrosynthesis of the fiber coating was performed under a constant potential of - 1.7 V by controlling the electrogeneration of OH^- in a solution containing sodium nitrate as the probase, 1,2,4,5-benzenetetracarboxylate acid as the ligand and copper nitrate as the cation source. The coating was characterized using field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The effective parameters on the electrosynthesis, extraction, and desorption processes were thoroughly optimized. Under the optimized conditions, metamphetamine (MAP) was quantified over a linear range of 0.90-1000.0 ng mL^-1 with R² > 0.997. A limit of detection of 0.1 ng mL^-1 was achieved, and intra- and inter-day relative standard deviations were found within the range 3.0-4.4% and 2.8-3.9%, respectively. Finally, the method was successfully applied to determination of MAP in urine samples with good recoveries in the range 85.0-102.5%. Graphical abstract Schematic representation of the in-situ electrochemical synthesis of a Cu-based metal-organic framework and its application in a headspace SPME procedure for the measuring methamphetamine in urine samples followed by GC-MS analysis.