Abstract

A tryptophan ionic liquid (TrpIL) decorated magnetic graphene oxide (Fe₃O₄@SiO₂-GO-TrpIL) nanocomposite has been prepared for magnetic solid-phase extraction of Sudan I–IV before their high performance liquid chromatography (HPLC) analysis. Fe₃O₄@SiO₂ nanoparticles loaded on graphene oxide endow the as-prepared nanocomposite with superparamagnetic performance, benefiting conveniently magnetic separation of the Sudan-absorbed nanocomposites from an aqueous phase. Both TrpIL and grapheme oxide make the Fe₃O₄@SiO₂-GO-TrpIL adsorbent possess high affinity and extraction efficiency toward target analytes, Taking full advantages of the adsorbent, each of Sudan I–IV could be accurately quantified in a linear range of 0.01–0.50 µg mL⁻¹ with the detection limit of 1.0 ng mL⁻¹ under the optimized conditions. A 10-fold enrichment factor was obtained. The present method was employed for the simultaneous determination of Sudan I–IV in chill and water samples with satisfactory results. The thermodynamic and kinetic investigations proved that the targets might be chemisorbed onto the Fe₃O₄@SiO₂-GO-TrpIL nanocomposite.

摘要

已经制备了色氨酸离子液体（TrpIL）装饰的磁性氧化石墨烯（Fe ₃ O ₄ @SiO ₂ -GO-TrpIL）纳米复合材料，用于苏丹I–IV的磁性固相萃取，然后进行高效液相色谱（HPLC）分析。负载在氧化石墨烯上的Fe ₃ O ₄ @SiO ₂纳米颗粒使制备的纳米复合材料具有超顺磁性能，从而有利于从水相中磁性分离苏丹吸收的纳米复合材料。TrpIL和氧化石墨烯均可生成Fe ₃ O ₄ @SiO ₂-GO-TrpIL吸附剂对目标分析物具有很高的亲和力和提取效率，利用吸附剂的全部优势，可以在0.01-0.50 µg mL ^-1的线性范围内准确定量苏丹I-IV的每种，检测限为1.0 ng mL ^-1在优化条件下。获得了十倍的富集因子。本方法用于同时测定冷水和水样中的苏丹I-IV，结果令人满意。热力学和动力学研究证明目标物可能被化学吸附到Fe ₃ O ₄ @SiO ₂ -GO-TrpIL纳米复合材料上。