Yang Clayton S C, Jin Feng, Swaminathan Siva R, Patel Sita, Ramer Evan D, Trivedi Sudhir B, Brown Ei E, Hommerich Uwe, Samuels Alan C
Opt Express. 2017 Oct 30;25(22):26885-26897. doi: 10.1364/OE.25.026885.
This is the first report of a simultaneous ultraviolet/visible/NIR and longwave infrared laser-induced breakdown spectroscopy (UVN + LWIR LIBS) measurement. In our attempt to study the feasibility of combining the newly developed rapid LWIR LIBS linear array detection system to existing rapid analytical techniques for a wide range of chemical analysis applications, two different solid pharmaceutical tablets, Tylenol arthritis pain and Bufferin, were studied using both a recently designed simultaneous UVN + LWIR LIBS detection system and a fast AOTF NIR (1200 to 2200 nm) spectrometer. Every simultaneous UVN + LWIR LIBS emission spectrum in this work was initiated by one single laser pulse-induced micro-plasma in the ambient air atmosphere. Distinct atomic and molecular LIBS emission signatures of the target compounds measured simultaneously in UVN (200 to 1100 nm) and LWIR (5.6 to 10 µm) spectral regions are readily detected and identified without the need to employ complex data processing. In depth profiling studies of these two pharmaceutical tablets without any sample preparation, one can easily monitor the transition of the dominant LWIR emission signatures from coating ingredients gradually to the pharmaceutical ingredients underneath the coating. The observed LWIR LIBS emission signatures provide complementary molecular information to the UVN LIBS signatures, thus adding robustness to identification procedures. LIBS techniques are more surface specific while NIR spectroscopy has the capability to probe more bulk materials with its greater penetration depth. Both UVN + LWIR LIBS and NIR absorption spectroscopy have shown the capabilities of acquiring useful target analyte spectral signatures in comparable short time scales. The addition of a rapid LWIR spectroscopic probe to these widely used optical analytical methods, such as NIR spectroscopy and UVN LIBS, may greatly enhance the capability and accuracy of the combined system for a comprehensive analysis.
这是首次关于同时进行紫外/可见/近红外和长波红外激光诱导击穿光谱（UVN + LWIR LIBS）测量的报告。在我们尝试研究将新开发的快速LWIR LIBS线性阵列检测系统与现有的快速分析技术相结合以用于广泛化学分析应用的可行性时，使用最近设计的同时UVN + LWIR LIBS检测系统和快速声光可调滤光器近红外（1200至2200 nm）光谱仪对两种不同的固体药片片剂（泰诺关节炎止痛片和百服宁）进行了研究。本工作中的每一个同时UVN + LWIR LIBS发射光谱都是由环境空气气氛中的单个激光脉冲诱导的微等离子体引发的。在UVN（200至1100 nm）和LWIR（5.6至10 µm）光谱区域中同时测量的目标化合物的独特原子和分子LIBS发射特征很容易被检测和识别，无需采用复杂的数据处理。在对这两种药片片剂进行无需任何样品制备的深度剖析研究中，可以轻松监测主导的LWIR发射特征从包衣成分逐渐过渡到包衣下方药物成分的过程。观察到的LWIR LIBS发射特征为UVN LIBS特征提供了互补的分子信息，从而增强了识别程序的稳健性。LIBS技术更具表面特异性，而近红外光谱能够以更大的穿透深度探测更多的块状材料。UVN + LWIR LIBS和近红外吸收光谱都已显示出在相当短的时间尺度内获取有用的目标分析物光谱特征的能力。在这些广泛使用的光学分析方法（如近红外光谱和UVN LIBS）中添加快速LWIR光谱探头，可能会大大提高组合系统进行综合分析的能力和准确性。
