对EDTA和Irganox抗氧化能力的比较研究
Dalal K Thbayh1,2,3, Marcin Palusiak4, Béla Viskolcz1,3
1Institute of Chemistry, University of Miskolc, 3515 Miskolc-Egyetemváros, Hungary.
Heliyon
|May 26, 2023
概括
乙二胺酸 (EDTA) 和伊尔加诺克斯 (Irg) 保护食品和包装免受氧化应激. 计算分析显示,EDTA与Irganox相比,具有更强的抗氧化能力.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
- 食品科学 食品科学 食品科学
背景情况:
- 由自由基引起的氧化应激会降解食品和聚合物包装,造成健康风险.
- 合成抗氧化剂对于防止材料恶化和保持食品质量至关重要.
- 了解抗氧化机制是开发有效的保护性添加剂的关键.
研究的目的:
- 为了比较乙烯基胺三酸 (EDTA) 和Irganox (Irg) 的抗氧化潜力.
- 研究它们在保护食品和聚合物包装免受氧化损伤方面的有效性.
- 使用计算方法阐明这些合成添加剂的抗氧化机制.
主要方法:
- 使用了密度函数理论 (DFT) 方法 (M05-2X和M06-2X).
- 计算包括键解离 (BDE),电离潜力 (IP),质子解离 (PDE),质子亲和力 (PA) 和电子转移 (ETE).
- 这些参数使用在气相中设置的6-311++G(2d,2p) 基数进行评估.
主要成果:
- 无论是EDTA还是Irganox都表现出显著的抗氧化能力.
- 根据计算的参数,EDTA的抗氧化能力高于Irganox.
- 这项研究首次直接比较EDTA和Irganox.的抗氧化特性.
结论:
- EDTA和Irganox是有效的合成抗氧化剂,用于食品保存和聚合物包装.
- 与Irganox相比,EDTA对氧化应激提供了更好的保护.
- 这些发现支持使用EDTA和Irganox来防止食品和材料的氧化恶化.
相关概念视频
01:18Effects of EDTA on End-Point Detection Methods
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Different methods, such as visual observance of metal-ion indicators, spectroscopic techniques, and potentiometric methods, can determine the endpoint of an EDTA titration.
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a...
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a...
315
01:26EDTA: Auxiliary Complexing Reagents
632
EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...
632
01:22EDTA: Chemistry and Properties
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Polydentate ligands are most widely used in complexometric titrations because they form more stable complexes with the metal ions than mono- or bidentate ligands due to the chelate effect. Examples of polydentate ligands are ethylenediaminetetraacetic acid (EDTA), crown ethers, and cryptands. The most important feature of optimal polydentate ligands is the ability to form 1:1 complexes in a single-step process. Amino carboxylic acid derivatives are frequently used as complexing agents. EDTA is...
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01:19Masking and Demasking Agents
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EDTA titrations may necessitate masking and demasking agents to temporarily protect a particular metal ion in a mixture from the EDTA reaction. These agents facilitate the sequential analysis of the metal ions by forming stable complexes with some—but not all—metal ions during certain steps.
There are many masking agents, such as cyanide, fluoride, triethanolamine, thiourea, and 2,3-bis(sulfanyl)propan-1-ol (formerly 2,3-dimercapto-1-propanol), with the masking agent chosen based on...
There are many masking agents, such as cyanide, fluoride, triethanolamine, thiourea, and 2,3-bis(sulfanyl)propan-1-ol (formerly 2,3-dimercapto-1-propanol), with the masking agent chosen based on...
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01:30EDTA: Direct, Back-, and Displacement Titration
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The EDTA titration types for metal ion analysis include direct titration, back-titration, and replacement titration.
Direct titration involves buffering the metal ion solution to the desired pH and directly titrating with standard EDTA until the endpoint. The optimum pH ensures a large conditional formation constant of metal−EDTA and visibility of the free indicator color in the solution. In addition, auxiliary complexing reagents are used to prevent the precipitation of metal hydroxides...
Direct titration involves buffering the metal ion solution to the desired pH and directly titrating with standard EDTA until the endpoint. The optimum pH ensures a large conditional formation constant of metal−EDTA and visibility of the free indicator color in the solution. In addition, auxiliary complexing reagents are used to prevent the precipitation of metal hydroxides...
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01:23EDTA: Indirect and Alkalimetric Titration
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Unlike direct titration, back-titration, and displacement titration, indirect titration is an EDTA titration method for quantifying anions. In the indirect titration method, anions are precipitated as their insoluble salts with excess metal ions. The filtrate containing the excess metal ions is directly titrated with standard EDTA until the endpoint is achieved. Another approach involves extracting the metal ion and back-titrating with standard EDTA to obtain the endpoint. In this way, the...
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