【作者】 王乐新；

【导师】 赵志敏；

【作者基本信息】 南京航空航天大学 ， 精密仪器及机械， 2009， 博士

【摘要】 光谱技术应用于生物组织的特性研究是生物医学光子学的一个热点课题,通过分析光诱导产生的光谱及其特性,研究生物大分子的结构或诊断生物组织病变,其目的是借助内源或外源性的荧光分析辅助阐明溶液状态下生物大分子的构象。本文探索研究了人体典型血样的光谱特征,对正常人体血清、高血糖血清及高甘油三脂血清的光谱学特性进行了实验研究和理论分析。主要研究成果如下:1.系统研究了温度、浓度、波长对血清荧光光谱的影响,从实验角度探讨了血清荧光强度随温度的变化规律;由于激发荧光、浓度淬灭和吸收作用的共同效果,导致血清的荧光光谱强度随血清浓度变化;血清的荧光光谱线型及峰值位置与激发光波长无关,荧光峰强度与激发光波长紧密相关,光谱有两个较强的发射区,中心波长在330nm和452nm处。此研究对光诱导荧光光谱诊断技术中血清样品温度、血清浓度、激发光波长的选择具有一定参考价值。从理论上给出了血清微弱发光的微观模型,探讨了发光强度随血清中血糖和甘油三脂浓度变化的规律。分析了正常血清和异常血清吸收光谱之间的差异,利用血清的吸光度来判断血清中甘油三脂是否异常。2.探索研究了不同浓度血清同步荧光光谱的变化规律和不同生化指标血清同步荧光光谱的特点。同波长差不同生化指标的血清,同步荧光出现了不同于正常血清的光谱特征,光谱的形状也不同。不同波长差血清同步荧光谱线的形状、精细结构不同,能很好地区分血清样品是正常还是发生了病变,为进一步的临床诊断研究提供了参考依据。3.探索研究了正常和异常血清的散射光谱和同一生化指标不同浓度血清散射光谱的规律。正常血清散射光谱与高血脂和高血糖血清散射光谱特征峰差异明显,峰值强度随血脂、血糖浓度增大而增大。峰值强度I446/I464和I615/I628比值随血糖浓度增加近似线性变化,高血脂血清散射光谱无此现象,可凭此区分高血糖和高血脂血清。4.研究了正常和异常血清荧光偏振光谱偏振度,进一步探索了偏振度随血清中血糖和甘油三脂浓度的变化规律,分析了不同荧光区域,血清中各荧光团之间能量转换机制及偏振度的变化现象。5.提出了基于分形理论的光谱分形特征分析方法,应用分形理论计算光谱曲线的分形维数,利用分形维数的差模识别不同血清光谱,为分形理论在光谱识别上应用作了初步探索。本文研究结果对研究光与血液相互作用的机理,借助血液的内源或外源性的发光特性进行临床诊断和治疗,以及研究血液中生物大分子的构象特点及变化规律提供理论和实验依据。更多还原

【Abstract】 Spectroscopy technology applied to research the characteristics of biological tissue is one of the hot subjects in the fields of biomedicine and photons. The structures of biomacromolecules are researched by the characteristics of spectrums excitated by ray. The purpose is to illustrate the structures of biomacromolecules in solution by the endogenetic or exogenous fluorescence analysis. And this could be used to diagnose the pathological changes of biological tissue. The spectral characteristics of typical human blood samples are studied detailedly in this paper and the main research contents and innovations are as follows:1. The influences of temperature, concentration and wavelength on fluorescence spectra of serums are investigated systematically. The change law of fluorescence intensity of the serums along with the temperature is discussed by experiments. The fluorescence intensity of the serums changes with the concentration because of excitation fluorescence, concentration quenching and absorption.The line type and peak position of the fluorescence spectrum of the serums are irrelevant to the excitation wavelength and the fluorescence intensity is closely related to the excitation wavelength. The spectrum has two relatively strong emitter regions, and the central wavelengths are 330nm and 452nm separately. The research result has important reference value to the selection of serum temperature, serum concentration and excitation wavelength in the diagnosis technology for induced fluorescence spectrum.The microcosmic model for ultra weak chemiluminescence of serum is theoretically analyzed. The change laws of the luminescence intensity along with the blood sugar and the three acids glyceride are investigated in detail. The differences between the absorption spectra of abnormal serum and that of normal serum are analyzed carefully. The normal or abnormal concentration of three acids glyceride in serum can be estimated by the absorbency of the serum.2. The synchronous fluorescence spectrums of serums respectively with different concentration and different biochemical parameters are researched. To the serums with same wavelength difference and different biochemical parameters, the synchronous fluorescence spectrums of these serums present differences from that of normal serums. To the serums with different wavelength difference, the figures and the fine structures of the synchronous fluorescence spectrums show obvious differences. By using these differences, the abnormal serums can be distinguished from the normal serums. Therefore, it provides reference for clinical diagnosis. 3. The scattering spectrums of normal serums and abnormal serums are researched, and the scattering spectrums of serums with same biochemical parameters and different concentrations are also studied. The scattering spectrums of abnormal serums, such as the serums with hyperlipidemia and the serums with hyperglycemia, have obvious differences from the spectrums of normal serums on the characteristic peaks. The peak values augment along with the increase of the blood lipids concentration and the blood sugar concentration. Moreover, the relationship between I446/I464 and blood sugar concentration, and the relationship between I615/I628 and blood sugar concentration are nearly linear. However, there is no similar phenomenon in the scattering spectrums of serums with hyperlipidemia. Hence, it can be used to distinguish between the serums with hyperglycemia and the serums with hyperlipidemia.4. The fluorescence polarization spectrums of normal serums and abnormal serums are also studied in this paper. When the concentrations of the blood sugar and the blood lipids in the serums are changed, the degree of polarization in the spectrums will vary. In different fluorescence areas, the energy transformation mechanism between fluorophores and the variety of polarization degrees are analyzed detailed.5. The fractal theory used to calculate the fractal dimensions of the spectrums is put forward. The differential modes of the fractal dimensions of spectrums of different serums are compared to distinguish. It provides some references for the fractal theory being applied in spectral recognition.The research results of this paper are in favor of studying the interaction mechanism between light and blood. It provides experimental and academic references for disease diagnosis and cure by dint of the blood endogenetic or exogenous radiation characteristics, and it is also helpful to research the structure and the changing rule of biomacromolecules in blood.更多还原