Burkitt M J, Gilbert B C
Department of Chemistry, University of York, UK.
Free Radic Res Commun. 1990;10(4-5):265-80. doi: 10.3109/10715769009149895.
Complementary hydroxylation assays and stopped-flow e.s.r. techniques have been employed in the investigation of the effect of various iron chelators (of chemical, biological and clinical importance) on hydroxyl-radical generation via the Haber-Weiss cycle and the ascorbate-driven Fenton reaction. Chelators have been identified which selectively promote or inhibit various reactions involved in hydroxyl-radical generation (for example, NTA and EDTA promote all the reactions of both the Haber-Weiss cycle and the ascorbate-driven Fenton reaction, whereas DTPA and phytate inhibit the recycling of iron in these reactions). The biological chelators succinate and citrate are shown to be relatively poor catalysts of the Haber-Weiss cycle, whereas they are found to be effective catalysts of .OH generation in the ascorbate-driven Fenton reaction. It is also suggested that continuous redox-cycling reactions between iron, oxygen and ascorbate may represent an important mechanism of cell death in biological systems.
互补羟基化测定法和停流电子自旋共振技术已被用于研究各种具有化学、生物学和临床重要性的铁螯合剂对通过哈伯-维希循环和抗坏血酸驱动的芬顿反应产生羟基自由基的影响。已鉴定出能选择性促进或抑制参与羟基自由基产生的各种反应的螯合剂（例如，NTA和EDTA促进哈伯-维希循环和抗坏血酸驱动的芬顿反应的所有反应，而DTPA和植酸抑制这些反应中铁的循环利用）。生物螯合剂琥珀酸盐和柠檬酸盐被证明是哈伯-维希循环相对较差的催化剂，而它们被发现是抗坏血酸驱动的芬顿反应中羟基自由基产生的有效催化剂。还表明铁、氧和抗坏血酸之间的连续氧化还原循环反应可能是生物系统中细胞死亡的重要机制。
