Real-time analysis of carbon monoxide isotopologues in biogenic gas samples via infrared laser spectroscopy

我们建议探索一种激光光谱方法，用于定量实时检测生物源一氧化碳（CO）。CO在许多生物系统的代谢过程中以低浓度产生和释放;例如，它是人类呼出气体的组成部分。除了主要丰富的同位素12 C16 O，我们计划将分析扩展到稀有的CO同位素，如13 C16 O。为此目的，腔泄漏光谱（CALOS）-一种使用连续波激光器的衰荡光谱的变体-似乎非常有前途; CALOS是最灵敏的高分辨率红外光谱技术之一。目前最小可检测吸收率已降至10-10/cm。CALOS方法对于所有需要最高灵敏度、特异性和快速响应时间的分析任务都非常有吸引力。拟议的工作将设置阶段，使这种方法适用于同位素选择性在线分析复杂的生物成因气体样品中的CO气体馏分。这些结果与生物医学和药理学研究相关，其中使用稳定同位素（如13 C）作为“示踪剂”实验的标记是一个关键问题。

We propose to explore a laser spectroscopic approach for quantitative real-time detection of biogenic carbon monoxide (CO). CO is generated and released in low concentrations during the metabolism of many biological systems; for example, it is a constituent of exhaled human breath. Next to the main abundant isotopic species 12C16O, we plan to extend the analysis to rare CO isotopologues, like 13C16O. For this purpose, cavity leak-out spectroscopy (CALOS) - a variant of ring-down spectroscopy with continuous-wave lasers - appears very promising; CALOS is one of the most sensitive high-resolution infrared spectroscopy techniques. The minimum detectable absorption is currently down to 10-10/cm. The CALOS approach is very attractive for all analytical tasks which require highest sensitivity, specificity, and fast response time. The proposed work shall set the stage for making this methodology applicable for the isotope-selective online analysis of CO gas fractions in complex biogenic gas samples. The results are of relevance for biomedical and pharmacological studies, where the use of stable isotopes, like 13C, as labels for "tracer" experiments is a key issue.