Determination of ametryn residues in fruit juice samples via electro-enhanced solid-phase microextraction using NiCo-LDH coated fiber and GC analysis

In this study, a robust and stable solid-phase microextraction (SPME) fiber was fabricated by electrochemically depositing nickel-cobalt layered double hydroxide (NiCo-LDH) onto a graphite pencil fiber (GPF). The developed method was specifically designed for analyzing fruit juice samples, including cherry, nectarine, plum, and apple juices. This modified fiber was employed as the working electrode in an electrically enhanced SPME (EE-SPME) technique for extracting ametryn, followed by its analysis via gas chromatography coupled with a flame ionization detector (GC-FID). Compared to conventional SPME, the EE-SPME approach demonstrated higher extraction efficiency for ametryn. Experimental parameters were optimized using central composite design (CCD), and the influence of each key variable was assessed. The developed EE-SPME-GC method showed a wide linear dynamic range (LDR) for ametryn detection, spanning 3.5-1000 ng mL -1 in deionized water and 7.0-1000 ng mL -1 in real samples. The method's detections limits (LOD) and quantification limits (LOQ) in fruit juice matrices ranged from 1.0-2.0 ng mL -1 and 3.5-7.0 ng mL -1 , respectively. Furthermore, precision evaluated by calculating the relative standard deviation (RSD) was in the range of 2.2-4.5%. Finally, the method's applicability was confirmed by successfully determining ametryn in fruit juice samples with relative recoveries ranging from 89.7% to 100.0%. • Electro-assisted microextraction with NiCo-LDH fiber for ametryn isolation • NiCo-LDH coating improves fiber properties and extraction efficiency • Method offers higher sensitivity than conventional microextraction • Reduced solvent use aligns with green chemistry principles • Reliable detection of ametryn in fruit juices using gas chromatography