Helmenstine A, Uziel M, Vo-Dinh T
Health and Safety Research Division, Oak Ridge National Laboratory, TN 37831-6101.
J Toxicol Environ Health. 1993 Oct-Nov;40(2-3):195-202. doi: 10.1080/15287399309531787.
Hazardous pollutants emitted from energy-related technologies, chemical industries, or waste materials are of increasing public concern because of their potential adverse health effects. Many pollutants have chemical groups of toxicological importance that can be characterized and detected by Raman spectroscopy. Raman spectroscopy, however, has not been widely used in trace organic detection, even though the information contained in a Raman spectrum is valuable for chemical identification. One limitation of conventional Raman spectroscopy is its low sensitivity, which often necessitates the use of powerful and costly laser sources for sample excitation. Raman spectroscopists have recently been able to analyze dilute biological samples as a result of enhancements in the Raman scattering cross section by factors up to 10(10) when a compound is adsorbed on or near a special electron-conducting surface. These spectacular enhancement factors of the normally weak Raman scattering process help overcome the low sensitivity of Raman spectroscopy through a combination of electromagnetic and chemical interactions between the analyte molecule and the surface. The technique associated with this phenomenon is known as surface-enhanced Raman scattering spectroscopy (SERS). The special conductive surface responsible for the scattering enhancement is referred to as a SERS substrate. For the past few years we have developed the SERS technique, using practical SERS-active substrate materials based on silver-coated microspheres deposited on glass. A wide variety of biomarkers have been investigated, including benzo[a]pyrene, dibenz[a,h]anthracene epoxides, 1,N9-ethenoadenine, 3,N4-ethenocytosine, and other substances. These biomarkers were measured at nanogram and subnanogram levels. The experimental results are of great analytical interest, since these chemicals are difficult to detect by other techniques, such as luminescence spectroscopy, because of the weak luminescence quantum yields of these DNA adducts. In this paper the potential usefulness of the SERS technique for assessing environmental and health effects from human exposure to toxic pollutants is demonstrated.
能源相关技术、化学工业或废料排放的有害污染物因其潜在的健康危害而日益受到公众关注。许多污染物具有毒理学重要性的化学基团，可通过拉曼光谱进行表征和检测。然而，尽管拉曼光谱中包含的信息对化学鉴定很有价值，但它尚未广泛用于痕量有机检测。传统拉曼光谱的一个局限性是其灵敏度较低，这通常需要使用强大且昂贵的激光源来激发样品。由于当化合物吸附在特殊的导电表面上或其附近时，拉曼散射截面可增强高达10(10)倍，拉曼光谱学家最近已能够分析稀释的生物样品。这些通常较弱的拉曼散射过程的显著增强因子通过分析物分子与表面之间的电磁和化学相互作用相结合，有助于克服拉曼光谱的低灵敏度。与这种现象相关的技术被称为表面增强拉曼散射光谱（SERS）。负责散射增强的特殊导电表面被称为SERS基底。在过去几年中，我们开发了SERS技术，使用基于沉积在玻璃上的涂银微球的实用SERS活性基底材料。已经研究了多种生物标志物，包括苯并[a]芘、二苯并[a,h]蒽环氧化物、1,N9-乙撑腺嘌呤、3,N4-乙撑胞嘧啶和其他物质。这些生物标志物在纳克和亚纳克水平进行了测量。实验结果具有很大的分析价值，因为由于这些DNA加合物的发光量子产率较低，这些化学物质很难通过其他技术（如发光光谱）检测到。本文展示了SERS技术在评估人类接触有毒污染物对环境和健康影响方面的潜在用途。
