Sharov V S, Dremina E S, Vladimirov Iu A
Biofizika. 1995 Mar-Apr;40(2):428-33.
The effect of the fluorescent dye 2,3,5,6-1H,4H-tetrahydro-9-(2'- benzoimidazolyl)-quinolizin-(9,9a,1-gh)coumarin (C-525) on the chemiluminescence (CL) flash kinetics accompanying Fe(2+)-induced free radical lipid hydroperoxide decomposition in low density lipoproteins (LDL) have been studied. C-525 was found to increase CL flash intensity by a factor of more than 2000 at the concentration of 4 mkM without any influence on the CL kinetics. The mechanism of the CL amplification is apparently energy transfer from the primary excited product of lipid peroxyl radical recombination to fluorescent level of the C-525. A concentration dependencies of CL amplification degree by C-525 on the LDL concentration were revealed to be bell-shaped, so that for 0.01 mg/ml of LDL protein the maximum amplification degree was observed at 4 mkM of C-525, whereas for 0.02 mg/ml of LDL--at 8 mkM. For the elucidation of these effects the properties of C-525 as hydrophobic fluorescent probe have been used. The concentration dependencies of C-525 fluorescence in the LDL suspension were found to be similar to that of CL amplification by C-525. These data pointed to the fact that concentration dependencies of the CL amplification by C-525 was conditioned by its accumulation in a hydrophobic phase of lipoproteins, so that the effective dye concentration was determined by both the amount of C-525 added to the suspension and the concentration of LDL.
研究了荧光染料2,3,5,6-1H,4H-四氢-9-(2'-苯并咪唑基)-喹嗪-(9,9a,1-gh)香豆素（C-525）对低密度脂蛋白（LDL）中Fe(2+)诱导的自由基脂质氢过氧化物分解伴随的化学发光（CL）闪光动力学的影响。发现C-525在4μM浓度下可使CL闪光强度增加2000多倍，且对CL动力学无任何影响。CL放大的机制显然是脂质过氧自由基重组的初级激发产物向C-525荧光能级的能量转移。C-525对CL的放大程度与LDL浓度的浓度依赖性呈钟形，因此对于0.01mg/ml的LDL蛋白，在4μM的C-525时观察到最大放大程度，而对于0.02mg/ml的LDL蛋白，在8μM时观察到最大放大程度。为了阐明这些影响，使用了C-525作为疏水荧光探针的特性。发现LDL悬浮液中C-525荧光的浓度依赖性与C-525对CL的放大相似。这些数据表明，C-525对CL的放大程度的浓度依赖性是由其在脂蛋白疏水相中的积累决定的，因此有效染料浓度由添加到悬浮液中的C-525量和LDL浓度共同决定。
