簡介生物檢體細胞之完整蛋白分子質譜技術

Introduction of the Biological Intact Protein Analysis by Mass Spectrometry

隨著蛋白體學成熟還有精準醫學進展，近年來在臨床檢測上針對疾病相關的蛋白質診斷需求也越來越多。傳統上利用蛋白質生化電泳的檢測方式，操作時間長且解析度較低，若選擇抗體抗原結合的檢測方式針對標的蛋白分析，亦有檢測抗體成本高的問題。質譜儀提供質荷比的分析資訊，近年來質譜儀也蓬勃應用於大分子質譜的檢測，本文亦將討論質譜相關技術，涵蓋儀器設計以及質量分析器中帶電粒子的運動情形，從物理學角度帶領讀者深入討論質譜技術的發展，並從現有大分子質譜分析方式，說明其中所涉及的技術與偵測極限。生物質譜檢體種類多元，包含臨床檢體、微生物樣本以及食品藥物等，整體生物質譜檢測質量範圍寬。然而，由於生物樣本在結構上複雜不易游離，使得蛋白質這類大質量分子仍有檢測上困難。目前在蛋白質質譜量測上可以分成兩種手段，一種是直接量測完整蛋白質，而另外一種則是將大分子蛋白質進行水解後再進行質譜分析。本篇研究將利用基質輔助雷射脫附游離法結合新型離子阱質譜儀，說明如何處理生物樣本，並在質譜儀上機後透過訊號後處理方式，提供了一種針對大分子完整蛋白的質譜量測方式。

With the development of proteomics and precision medicine, it is increasingly using protein targets for disease diagnosis and prediction. Two often-in-use methods are electrophoresis, which is time-consuming and with lower accuracy, and conjugation of antigen and antibody, which can identify specific proteins, yet, is a bit expensive for each detection. Alternatively, a mass spectrometer (MS) can provide the information of mass to charge ratio (m/z), such that recent MS techniques have been accordingly applied in clinical, microbes, food safety, and drug development. Here, we will introduce a MS method for the detection of large, and intact biological molecules. Over the variety of mass spectrometers, we will discuss all its instrumentation via the motion of in-trap charged particles. Usually, it is not easy to ionize the intact protein, for its large mass and complicated structure. Thus, protein research indirectly uses enzyme digestion to cut protein into peptide pieces for traditional MS analysis. Here, for the direct detection of intact proteins, the method of matrix-assisted laser desorption ionization (MALDI) is tactically arranged nearby the inside of the ion trap. Together with one innovative charge detector, phase-modulated spectrometry can be introduced for intact molecular ion analysis.