Mass spectrometry imaging (MSI) is an emerging high-tech "photography" method combining mass spectrometry and image visualization technologies, which can simultaneously monitor the spatial distribution of multiple molecules in biological samples. In recent years, the characteristics of this technology have been used to visually study the distribution of drugs in hair, among which matrix-assisted laser desorption ionization-mass spectrometry imaging(MALDI-MSI) technology has been most widely applied in hair analysis. Based on the principle of MALDI-MSI technology, this paper discusses the key technical elements of MALDI-MSI technology applied to hair analysis and reviews the research achievements of MSI in hair analysis. It concludes that improving the ionization efficiency, resolution, sensitivity and stability of MALDI-MSI technology remains the future exploration direction, and simplifying data analysis and establishing databases will help promote MALDI-MSI as a routine analytical technique for hair analysis.
质谱成像（mass spectrometry imaging，MSI）是一种结合质谱技术和影像可视化技术的新兴高科技“拍照”手段，可以同时监测生物样品中多种分子的空间分布情况。近年来，利用该技术特性对毛发中药物的分布情况进行可视化研究，其中以基质辅助激光解吸电离-质谱成像（matrix-assisted laser desorption ionization-mass spectrometry imaging，MALDI-MSI）技术在毛发分析中的应用最为广泛。本文基于MALDI-MSI技术的原理，探讨其应用于毛发分析的关键技术要素，梳理毛发MSI分析的研究成果，认为提高MALDI-MSI技术的电离效率、分辨率、灵敏度和稳定性依旧是未来的探索方向，简化数据分析和建立数据库将有助于推动MALDI-MSI成为毛发中毒（药）物分析的常规分析技术。.
Keywords: data processing; forensic medicine; hair; key technology; matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI); review; toxicological analysis; visualization.