Bilińska Barbara, Pilawa B, Zawada Z, Wylegała E, Wilczok T, Dontsov A E, Sakina N L, Ostrovsky M A, Ilyasova V B
Department of Physical Pharmacy, Medical University of Silesia, Sosnowiec, Poland.
Spectrochim Acta A Mol Biomol Spectrosc. 2002 Aug;58(10):2257-64. doi: 10.1016/s1386-1425(01)00695-3.
Electron spin resonance (ESR) examinations of human retinal pigment epithelium melanosomes isolated from eyes of young and old donors were carried out. The examined ESR signal was a single line, which is characteristic for free radicals of eumelanin o-semiquinones. The content of free radicals related to melanosomes dry weight for samples from older donors (ages over 45 years) were higher than for sample from younger donors (between 14 and 22 years). Simultaneously, the content of free radicals calculated for one melanosome is constant and does not depend on age. The homogeneous broadening of the recorded ESR lines shows that there are no isolated spin packets in all investigated melanin samples. Slow spin-lattice (T1 approximately 10(-5) s) and fast spin-spin (T2 approximately 10(-8) s) relaxation processes occur in these samples. Saturation of the ESR lines at low microwave power was measured. High concentration of free radicals in melanosome samples was responsible for the fast spin-spin relaxation process.
对从年轻和老年供体眼中分离出的人视网膜色素上皮黑素小体进行了电子自旋共振（ESR）检查。所检测的ESR信号为单线，这是真黑素邻苯二酚半醌自由基的特征。老年供体（年龄超过45岁）样本中与黑素小体干重相关的自由基含量高于年轻供体（14至22岁）样本。同时，计算得出的单个黑素小体中的自由基含量是恒定的，且不依赖于年龄。记录的ESR谱线的均匀展宽表明，在所有研究的黑色素样本中均不存在孤立的自旋包。这些样本中发生了缓慢的自旋晶格（T1约为10^(-5) s）和快速的自旋 - 自旋（T2约为10^(-8) s）弛豫过程。测量了低微波功率下ESR谱线的饱和情况。黑素小体样本中高浓度的自由基导致了快速的自旋 - 自旋弛豫过程。
