Takeda Sen, Yoshimura Kentaro, Tanihata Hiroshi
Department of Anatomy and Cell Biology, University of Yamanashi School of Medicine;
Department of Anatomy and Cell Biology, University of Yamanashi School of Medicine.
J Vis Exp. 2020 Feb 19(156). doi: 10.3791/59942.
Mass spectrometry (MS) is a powerful tool in analytical chemistry because it provides very accurate information about molecules, such as mass-to-charge ratios (m/z), which are useful to deduce molecular weights and structures. While it is essentially a destructive analytical method, recent advancements in the ambient ionization technique have enabled us to acquire data while leaving tissue in a relatively intact state in terms of integrity. Probe electrospray ionization (PESI) is a so-called direct method because it does not require complex and time-consuming pretreatment of samples. A fine needle serves as a sample picker, as well as an ionization emitter. Based on the very sharp and fine property of the probe tip, destruction of the samples is minimal, allowing us to acquire the real-time molecular information from living things in situ. Herein, we introduce three applications of PESI-MS technique that will be useful for biomedical research and development. One involves the application to solid tissue, which is the basic application of this technique for the medical diagnosis. As this technique requires only 10 mg of the sample, it may be very useful in the routine clinical settings. The second application is for in vitro medical diagnostics where human blood serum is measured. The ability to measure fluid samples is also valuable in various biological experiments where a sufficient volume of sample for conventional analytical techniques cannot be provided. The third application leans toward the direct application of probe needles in living animals, where we can obtain real-time dynamics of metabolites or drugs in specific organs. In each application, we can infer the molecules that have been detected by MS or use artificial intelligence to obtain a medical diagnosis.
质谱分析法（MS）是分析化学中的一种强大工具，因为它能提供有关分子的非常准确的信息，比如质荷比（m/z），这对于推断分子量和分子结构很有用。虽然它本质上是一种破坏性分析方法，但常压电离技术的最新进展使我们能够在组织完整性方面保持相对完整的状态下获取数据。探针电喷雾电离（PESI）是一种所谓的直接方法，因为它不需要对样品进行复杂且耗时的预处理。一根细针既作为样品采集器，又作为电离发射器。基于探针尖端非常尖锐和精细的特性，对样品的破坏最小，这使我们能够原位从生物活体中获取实时分子信息。在此，我们介绍PESI-MS技术的三种应用，这些应用将对生物医学研究与开发有用。一种应用涉及对固体组织的分析，这是该技术在医学诊断方面的基本应用。由于该技术仅需要10毫克样品，所以在常规临床环境中可能非常有用。第二种应用是用于体外医学诊断，即测量人血清。在各种生物学实验中，当无法提供足够体积的样品用于传统分析技术时，测量液体样品的能力也很有价值。第三种应用倾向于将探针针直接应用于活体动物，在这种情况下我们可以获得特定器官中代谢物或药物的实时动态信息。在每种应用中，我们都可以推断通过质谱分析法检测到的分子，或者使用人工智能来获得医学诊断。
