Rapid detection of an anthrax biomarker by surface-enhanced Raman spectroscopy
Rapid detection of an anthrax biomarker by surface-enhanced Raman spectroscopy
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DOI：
10.1021/ja043623b
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发表时间：
2005-03-30
影响因子：
15
通讯作者：
Van Duyne, RP
中科院分区：
文献类型：
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作者：
Zhang, XY;Young, MA;Van Duyne, RP
一种适用于第一反应者使用低成本、电池供电的便携式拉曼光谱仪检测炭疽孢子的快速检测方案已经开发出来。利用表面增强拉曼光谱（SERS）在纳米球（AgFON）衬底上的银膜上研究了无害的炭疽芽孢杆菌模拟物枯草芽孢杆菌孢子。二吡啶酸钙（CaDPA）是芽孢杆菌孢子的生物标志物，在硝酸中超声有效提取，SERS快速检测。制备了适合750 nm激光激发的AgFON表面，并用紫外-可见漫反射光谱和SERS对其进行了表征。提取的CaDPA在10(-14)-10(-12)M的孢子浓度范围内测量SERS信号，确定AgFON表面的饱和结合能力并计算吸附常数（k -孢子= 1.7 × 10(13) M-1）。目前，11分钟的程序能够达到-2.6 × 10(3)个孢子的检测限（LOD），低于10(4)个孢子的炭疽感染剂量。本文提供的数据还表明，预制AgFON基板在使用前的保质期可以长达40天。最后，这些传感能力已成功地从实验室光谱仪过渡到现场便携式仪器。利用该技术，在放置1个月的AgFON底物上检测到10(4)个芽孢杆菌孢子，数据采集周期为5 s。这种SERS传感器的速度和灵敏度表明，该技术可以作为潜在有害环境样品的现场分析的可行选择。
A rapid detection protocol suitable for use by first-responders to detect anthrax spores using a low-cost, battery-powered, portable Raman spectrometer has been developed. Bacillus subtilis spores, harmless simulants for Bacillus anthracis, were studied using surface-enhanced Raman spectroscopy (SERS) on silver film over nanosphere (AgFON) substrates. Calcium dipicolinate (CaDPA), a biomarker for bacillus spores, was efficiently extracted by sonication in nitric acid and rapidly detected by SERS. AgFON surfaces optimized for 750 nm laser excitation have been fabricated and characterized by UV-vis diffuse reflectance spectroscopy and SERS. The SERS signal from extracted CaDPA was measured over the spore concentration range of 10(-14)-10(-12) M to determine the saturation binding capacity of the AgFON surface and to calculate the adsorption constant (K-spore = 1.7 x 10(13) M-1). At present, an 11 min procedure is capable of achieving a limit of detection (LOD) of -2.6 x 10(3) spores, below the anthrax infectious dose of 10(4) spores. The data presented herein also demonstrate that the shelf life of prefabricated AgFON substrates can be as long as 40 days prior to use. Finally, these sensing capabilities have been successfully transitioned from a laboratory spectrometer to a field-portable instrument. Using this technology, 10(4) bacillus spores were detected with a 5 s data acquisition period on a 1 month old AgFON substrate. The speed and sensitivity of this SERS sensor indicate that this technology can be used as a viable option for the field analysis of potentially harmful environmental samples.