Magalhães Luís M, Segundo Marcela A, Reis Salette, Lima José L F C, Estela José Manuel, Cerdà Víctor
REQUIMTE, Serviço de Química-Física, Faculdade de FarmAcia, Universidade do Porto, Rua Aníbal Cunha, 164, 4099-030 Porto, Portugal.
Anal Chem. 2007 May 15;79(10):3933-9. doi: 10.1021/ac0700068. Epub 2007 Apr 11.
In the present work, a chemiluminometric automatic flow methodology for the in vitro determination of hypochlorous acid scavenging capacity, under pH and concentration conditions similar to those found in vivo, is proposed. As the pH found in physiological conditions (7.4) and the pH required for the chemiluminescence detection reaction (>10) are different, the multisyringe flow injection analysis features were exploited to perform the in-line reaction of HOCl and the scavenger molecule at physiological pH prior to reaction of the remaining HOCl with luminol at alkaline conditions. These two reactions were carried out in about 3 s, allowing the determination of fast reacting antioxidants, in a time frame closer to in vivo generation of HOCl when compared to previously described methods. The developed method was applied to nonsteroidal antiinflammatory drugs of different chemical families, and positive controls (cysteine, gallic acid, lipoic acid). The HOCl scavenging capacity was evaluated at pH 7.4 and 10.0; different results were found for oxicam derivatives, providing evidence that the pH of in vitro methods should be carefully selected to allow assumptions about putative in vivo effects.
在本研究中，提出了一种化学发光自动流动方法，用于在类似于体内发现的pH和浓度条件下体外测定次氯酸清除能力。由于生理条件下的pH值（7.4）与化学发光检测反应所需的pH值（>10）不同，因此利用多注射器流动注射分析功能，使次氯酸（HOCl）与清除剂分子在生理pH下进行在线反应，然后剩余的HOCl在碱性条件下与鲁米诺反应。这两个反应在约3秒内完成，与先前描述的方法相比，能够在更接近体内HOCl生成的时间范围内测定快速反应的抗氧化剂。所开发的方法应用于不同化学家族的非甾体抗炎药以及阳性对照（半胱氨酸、没食子酸、硫辛酸）。在pH 7.4和10.0下评估了HOCl清除能力；发现昔康衍生物有不同结果，这表明体外方法的pH值应仔细选择，以便对假定的体内效应进行推测。
