Gutteridge J M, Hou Y Y
Division of Antibiotics and Chemistry, National Institute for Biological Standards and Control, Holly Hill, Hampstead, London.
Free Radic Res Commun. 1986;2(3):143-51. doi: 10.3109/10715768609088066.
The sensitivity of the bleomycin assay for loosely-bound iron depends on the concentration of bleomycin and ascorbic acid and the pH of the reaction. The non-haem-iron proteins transferrin, conalbumin and ferritin release iron at an acid pH value, whereas the haem-iron proteins release iron more readily at an alkaline pH. In addition, haem proteins are liable to release iron when peroxides are present. Organic peroxides and hydrogen peroxide can be produced during the bleomycin reaction leading to iron release from haem proteins. However, this can be prevented from reacting with bleomycin by adding zinc ions to the reaction following addition of the sample. Iron already bound to bleomycin is not displaced by zinc whereas zinc bound to bleomycin is not displaced by iron allowing 'free' and 'released' iron to be discriminated.
博来霉素检测法对松散结合铁的灵敏度取决于博来霉素和抗坏血酸的浓度以及反应的pH值。非血红素铁蛋白转铁蛋白、伴清蛋白和铁蛋白在酸性pH值下释放铁，而血红素铁蛋白在碱性pH值下更容易释放铁。此外，当存在过氧化物时，血红素蛋白容易释放铁。在博来霉素反应过程中会产生有机过氧化物和过氧化氢，导致血红素蛋白释放铁。然而，在加入样品后向反应中加入锌离子可以防止这种情况与博来霉素发生反应。已经与博来霉素结合的铁不会被锌取代，而与博来霉素结合的锌不会被铁取代，从而可以区分“游离”铁和“释放”铁。
