Preparation of cucurbit[6]uril-modified polymer monolithic column for microextraction of nitroaromatics

Abstract

Monolithic poly(glycidyl methacrylate-co-ethylene dimethacrylate) capillary columns incorporated with cucurbit[6]uril monorotaxane (CB[6]MR) were prepared and used in polymer monolith microextraction (PMME) for the separation and preconcentration of nitroaromatics. The introduction of CB[6]MR to the glycidyl methacrylate-based monolith enhanced the column efficiency by 24.5–35.5 fold because of the hydrophobic interaction, electrostatic interaction, hydrogen bonds, and π–π interaction between CB[6]MR and nitroaromatics. An orthogonal experiment design, L₁₆ (4⁵), was applied to arrange and optimize the experimental conditions. Under the optimum conditions, nitroaromatics were simultaneously determined with good linearity (R² > 0.9990) and low limit of quantification (0.069–0.163 ng mL⁻¹ at a signal-to-noise ratio of 10). The developed method was applied for the determination of nitroaromatics in water and blood samples, illustrating satisfactory recovery (83.2–107.9% and 88.2–112.5%) and reproducibility (relative standard deviations of 4.1–11.2% and 2.1–9.6%).