人体血清中胆红素荧光光谱初步分析

The Preliminary Analysis on the Fluorescence Spectra of Bilirubin in Human Serum

利用分子荧光和紫外-可见吸收光谱仪分别测定了在模拟生理条件下的胆红素、胆红素和牛血清白蛋白混合溶液的荧光光谱和吸收光谱,同时也测定了一些体检者血清样品的荧光发射光谱。实验结果表明:不同情况下的胆红素溶液具有不同的荧光光谱和吸收光谱;血清白蛋白对胆红素荧光具有增敏效应。此外,初步认为所测得的人体血清样品位于约524 nm处的荧光不是主要来自于人体血清中白蛋白结合形式的胆红素组分贡献。

Bilirubin is one of important endogenous fluorophores in human serums. Bilirubin, excited by some wavelengths of light, can emit fluorescence in the range of 500 to 600 nm. There are four forms of bilirubin in human serum; different bilirubin fractions have different physiological meaning and different fluorescent spectra. Investigation of bilirubin fluorescence in human serum will provide some theoretic basis and references for diagnosing some diseases by the autofluorescence of human serum. The fluorescence and absorption spectra of bilirubin solutions and mixed solutions of bilirubin and bovine serum albumin under normal physiological conditions, and the fluorescence spectra of nmrnal human serum samples were measured and analyzed. The experimental results showed that different bilirubin solutions had different fluorescence and absorption spectra; serum albumin has a fluorescent enhancement effect on the fluorescence of bilirubin. BR ＋ BSA mixed solutions aging for two days have different absorption and fluorescence spectra compared with BR ＋ BSA mixed solutions. Moreover, it was educed that the fluorescent peaks located about 525 nm did not mainly derive from the contribution of bilirubin-albumin complex in human serum sampies. In other words, the concentration of Bs fraction in normal human serum may be very low. Human serum compositions are very complex. There are many endogenous fluorophores that can emit fluorescence in the range of 500 nm to 600 nm. In this experiment, the measured fluorescent peaks of serum samples may come from the contributions of other bilirubin fractions or β-carotene and riboflavin derivatives. The above conclusion was drawn based on some healthy serum samples. But in other cases, such as diseases of jaundice and hepatitis, Bs fraction may demonstrate stronger fluorescence. As a result, its fluorescence should be observed.