REQUIMTE, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua Aníbal Cunha, Porto, Portugal.
Chemosphere. 2011 Mar;82(11):1620-8. doi: 10.1016/j.chemosphere.2010.11.046. Epub 2010 Dec 23.
An automated assay for the evaluation of the influence of ionic liquids on the activity of catalase was developed. The activity and inhibition assays were implemented in a sequential injection analysis (SIA) system and intended to contribute for the estimation of the toxicity of the tested compounds. The fast developed methodology was based on the oxidation of the non-fluorescent probe amplex red, in the presence of H₂O₂, to produce resorufin, a strong fluorescent compound. Catalase activity was monitored by the decreased of the fluorescence intensity due to the consumption of H₂O₂ by the enzyme. The activity assays were performed in strictly aqueous media and in the presence of increasing concentrations of seven commercially available ionic liquids and sodium azide, a strong inhibitor of catalase. IC₅₀ values between 0.15 and 2.77 M were obtained for the tested compounds, revealing distinct inhibitory effects. This allowed us to perform some considerations about the toxicity of the tested cations and anions. The developed SIA methodology showed to be robust and exhibited good repeatability in all the assay conditions. On the other hand, it proved to be in good agreement with the actual concerns of "Green Chemistry" since it involved the consumption of less than 200 μL of reagents and the production of only 1.7 mL of effluent (per cycle) and at the same time reduced the operator exposure resulting in increased environmental and human safety.
开发了一种用于评估离子液体对过氧化氢酶活性影响的自动化分析方法。活性和抑制分析在顺序注射分析（SIA）系统中进行，旨在为测试化合物的毒性评估提供依据。快速发展的方法基于非荧光探针 Amplex Red 在 H₂O₂存在下氧化生成强烈荧光化合物 Resoruin。过氧化氢酶活性通过酶消耗 H₂O₂导致荧光强度降低来监测。活性分析在严格的水性介质中进行，并在存在七种市售离子液体和过氧化氢酶强抑制剂叠氮化钠的情况下进行。测试化合物的 IC₅₀值在 0.15 到 2.77 M 之间，显示出明显的抑制作用。这使我们能够对测试阳离子和阴离子的毒性进行一些考虑。所开发的 SIA 方法表现出良好的稳健性，并在所有分析条件下均表现出良好的重复性。另一方面，它符合“绿色化学”的实际关注点，因为它涉及消耗少于 200 μL 的试剂，仅产生 1.7 毫升的流出物（每个循环），同时减少了操作人员的暴露，从而提高了环境和人员安全。
