Hybrid Cartridges Based on Metal-Organic Frameworks: A Cost-Reducing and Sensitive Green Alternative for the Detection of Glyphosate and Its Metabolite AMPA.

Exposure to pesticides is associated with harmful effects on the environment and public health. There is an urgent need to develop alternative detection methods to ensure that water supply sources remain free from pesticides. In this work, an iron terephthalate metal-organic framework from the family MIL-101 was studied as an alternative adsorbent for the fabrication of hybrid solid-phase extraction (SPE) cartridges for the determination of glyphosate and aminomethyl-phosphonic acid (AMPA) in tap and river water samples by chromatographic analysis. Hybrid cartridges were fabricated based on synthesized MIL-101-(Fe) by a microwave-assisted method and packed with silica C18 inside empty commercial cartridges. Then, the general conditions for the SPE of selected pesticides were studied in detail. The proposed SPE methodology enabled the achievement of improved analytical results compared to conventional adsorbents, including limits of detection of 1.2 and 3.9 ng/mL, along with enrichment factors of 27.7 and 56 for GLY and AMPA, respectively. Extraction recoveries ranged from 76% to 108%, with satisfactory relative standard deviation values below 3.5% (intraday precision, n = 5) and 9.4% (interday precision, n = 5). Linear ranges were observed from 10 to 1000 ng/mL, with determination coefficients exceeding 0.997. The obtained results suggest the successful employment of MIL-101-(Fe) in alternative and practical methodologies for the pretreatment of water samples, facilitating the determination of pesticides and diminishing the harmful impacts of derivatization steps.