Laser Wavelength Dependence of Background Fluorescence in Raman Spectroscopic Analysis of Synovial Fluid from Symptomatic Joints.
Laser Wavelength Dependence of Background Fluorescence in Raman Spectroscopic Analysis of Synovial Fluid from Symptomatic Joints.
复制标题
有症状关节滑液拉曼光谱分析中背景荧光的激光波长依赖性。
DOI：
10.1002/jrs.4338
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Akkus,Ozan
中科院分区：
文献类型：
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作者：
Yang,Shan;Li,Bolan;Slipchenko,MikhailN;Akkus,Anna;Singer,NoraG;Yeni,YenerN;Akkus,Ozan
痛风是一种疾病过程，关节滑液中晶体的成核和生长会引起疼痛的关节炎样症状。拉曼光谱正在发展成为识别这类晶体的潜在诊断工具；然而，在克服背景荧光的同时获得足够的拉曼信号仍然是一个主要的挑战。目前的研究重点是评估在532-700 nm范围内的激发是否会提供比标准785 nm更强的信号强度，同时不受背景荧光的阻碍。我们对出现痛风样症状的患者(有症状)和对照组(无症状)的滑液的荧光光谱、吸收光谱和拉曼光谱进行了表征。建立了一种从滑液中分离晶体的消化和过滤方法，同时降低了有机负荷。在532~785 nm的激发波长范围内，观察了拉曼光谱的光谱分布和光漂白动力学。吸光度和荧光图谱表明，消化和过滤可以有效地从有症状的滑液中提取晶体，而不会引入额外的荧光。在532 nm、660 nm、690 nm和785 nm处的拉曼光谱分析表明，无症状和有症状的样品在700 nm以下的激发波长都有明显的荧光，这要么阻碍了拉曼信号的收集，要么需要延长光漂白的时间。在不使用光漂白的情况下，基于拉曼光谱的诊断在最长激发波长为785 nm时更可行。这项研究进一步证明，在785 nm激发下，基于近红外(NIR)OEM的低成本拉曼系统具有足够的灵敏度来识别从滑液中分离出来的晶体。总而言之，虽然较低的激发波长提供了更大的信号，但荧光需要近红外波长来对滑膜吸出物中观察到的晶体进行拉曼分析。版权所有©2013 John Wiley&Sons，Ltd.
Gout is a disease process where the nucleation and growth of crystals in the synovial fluid of joints elicit painful arthritis‐like symptoms. Raman spectroscopy is evolving as a potential diagnostic tool in identifying such crystals; however, attainment of sufficient Raman signal while overcoming the background fluorescence remains as a major challenge. The current study focused on assessing whether excitation in 532–700 nm range will provide greater signal intensity than the standard 785 nm while not being impeded by background fluorescence. We characterized the fluorescence spectra, absorption spectra and Raman spectra of synovial fluid from patients who presented ‘gout‐like symptoms’ (symptomatic) and controls (asymptomatic). A digestion and filtration method was developed to isolate crystals from synovial fluid while reducing the organic burden. Spectral profile and photobleaching dynamics during Raman spectroscopy were observed under an excitation wavelength range spanning 532 to 785 nm. Absorbance and fluorescence profiles indicated the digestion and filtration worked effectively to extract crystals from symptomatic synovial fluid without introducing additional fluorescence. Raman spectral analyses at 532 nm, 660 nm, 690 nm and 785 nm indicated that both asymptomatic and symptomatic samples had significant levels of fluorescence at excitation wavelengths below 700 nm, which either hindered the collection of Raman signal or necessitated prolonged durations of photobleaching. Raman‐based diagnostics were more feasible at the longest excitation wavelength of 785 nm without employing photobleaching. This study further demonstrated that a near‐infrared (NIR) OEM‐based lower‐cost Raman system at 785 nm excitation has sufficient sensitivity to identify crystals isolated from the synovial fluid. In conclusion, while lower excitation wavelengths provide greater signal, the fluorescence necessitates NIR wavelengths for Raman analysis of crystal species observed in synovial aspirates. Copyright © 2013 John Wiley & Sons, Ltd.