Successful synthesis of eco-friendly Metal-Organic framework ([Ni(BDC)]n) allows efficient extraction of multiresidues pesticides and dyes from fish samples

Abstract

Contaminants such as pesticides and dyes pose substantial challenges to environmental and human health, especially when found in aquatic ecosystems and ingested through the food chain. This requires the development of methods that are efficient, safe and environmentally friendly. In this scenario, this study presents the synthesis and characterization of a metal–organic framework (MOF), specifically [Ni(BDC)]n, designed as a solid adsorbent for the determination of pesticides, including atrazine, bifenthrin, chlorpyrifos, endrin, heptachlor, flutriafol and permethrin, as well as dyes such as crystal violet (CV) and Congo red (CR) in fish samples. Using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), X-ray Diffraction (XRD), and Brunauer-Emmett-Teller (BET), we verified the success of the MOF synthesis. BET analysis indicated MOF surface area and total pore volume of 2700 m2/g and 0.0136 cm3 g−1, respectively. The adsorption study revealed high affinity of the MOF for the target analytes, with qmax = 208.33 mg g−1 for pesticides and qmax = 4.18 mg g−1 for dyes. The kinetic study demonstrated that the adsorption mechanism follows a pseudo-second order model for all analytes. Furthermore, employing [Ni(BDC)]n, we have developed an efficient extraction method using Matrix-Solid Phase Dispersion (MSPD) combined with Gas Chromatography-Mass Spectrometry (GC–MS) and UV/Vis spectrophotometry for determination of pesticide and dyes, respectively, with pre-concentration factor ranging from 10 to 100 times for the studied analytes. The methods showed satisfactory linearity for both contaminants (pesticides and dyes), with recovery efficiency ranging from 81-103 % and precision < 13 % (n = 3) for the analytes. Linear ranges covering 10.0–500.0 μg L−1 (R2 > 0.995) for pesticides and 100.0–1000.0 μg L−1 (R2 > 0.988) for dyes. The limits of detection (LOD) and quantification (LOQ) ranged from 0.5-1.6 μg L−1 and 1.7–5.6 μg L−1 for pesticides, respectively, while for dyes, LOD and LOQ ranged from 2.0-12.0 μg L−1 and 7.6–39.6 μg L−1, respectively. These results highlight the potential of [Ni(BDC)]n as a promising material for efficient and selective extraction in the sustainable determination of pesticides and dyes in fish samples, with satisfactory reuse.