Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is used for the first time to characterize Cinchona alkaloids in natural Cinchona bark and commercial Cinchona extracts. ToF-SIMS analysis of quinine (Qn), a major Cinchona alkaloid, provides significant molecular fragments, which can be used in the fast qualitative screening of Qn and related compounds in small amounts of Cinchona bark and extract. Conventional approaches for natural product analysis such as bark are time-consuming and typically require large amounts of samples and significant amounts of organic solvents for extensive liquid extraction as well as liquid chromatography for analyte separation from the matrix before detection. In this study, it is demonstrated that ToF-SIMS can be used for the direct analysis and fast qualitative screening (less than 10 minute analysis time) of Cinchona alkaloids. It is also a greener approach than chromatography-based approaches because it uses less sample material and no organic solvents. Before ToF-SIMS analysis, the bark surface topography and roughness were analyzed using 3D laser microscopy. ToF-SIMS results in this study were validated by complementary high performance liquid chromatography-MS results. This work shows the potential of ToF-SIMS in the screening of pharmaceutically relevant compounds that are present in natural samples such as bark and extracts.

中文翻译：

---

使用飞行时间二次离子质谱法 直接分析天然金鸡纳树皮和商业提取物中的生物碱†

飞行时间二次离子质谱（ToF-SIMS）首次用于表征天然金鸡纳树皮和市售金鸡纳提取物中的金鸡纳生物碱。奎宁（Qn）是一种主要的金鸡纳生物碱的ToF-SIMS分析提供了重要的分子片段，可用于快速定性筛选少量金鸡纳中的Qn和相关化合物树皮和提取物。用于天然产物分析（例如树皮）的常规方法非常耗时，并且通常需要大量样品和大量有机溶剂才能进行广泛的液体萃取，以及在检测前从基质中分离分析物的液相色谱法。在这项研究中，证明了ToF-SIMS可用于Cinchona的直接分析和快速定性筛选（不到10分钟的分析时间）生物碱。与基于色谱的方法相比，它也是一种更环保的方法，因为它使用的样品材料更少，并且没有有机溶剂。在进行ToF-SIMS分析之前，使用3D激光显微镜对树皮的表面形貌和粗糙度进行了分析。补充高效液相色谱-MS结果验证了本研究中的ToF-SIMS结果。这项工作显示了ToF-SIMS在筛选天然样品（例如树皮和提取物中）中存在的药物相关化合物方面的潜力。