未知物结构鉴定、背景离子干扰和空间分辨率是目前制约高分辨质谱化学成像的重要因素。本项目旨在摆脱基质辅助激光解吸离解软电离方法的局限，重点研究纳秒脉冲激光场和静电场中，量子点半导体纳米晶体的光电离（多光子电离和隧道电离）过程及其与电子受体分子的多层次相互作用，包括结合型电子俘获、离解型电子俘获和电子脱离等基本科学问题，揭示不同材料性质、颗粒大小和形状对量子点纳米晶体光电离过程的影响，研究量子点表面修饰方法及光催化偶联自由基反应。通过特异性电子俘获离解，提高未知物结构鉴定能力、质谱图像分辨率和选择性电离能力,筛选靶向重要受体蛋白的光电子俘获质谱探针。利用所建立的高分辨质谱化学成像方法，探索乳腺癌的分子病理分级和分型，发现正常细胞向癌细胞发展过程中的早期生物分子标志物。

Currently, mass spectrometric imaging of tissue slices is mainly limited by the capability of structural identification, background interferences and spatial resolution. This work is aimed to develop a new technique that can overcome the limit of the soft ionization technique based on matrix assisted laser desorption ionization . Research efforts will be focused on fundamental sciences in photo-ionization of semiconductor nano-crystals of quantum dots (including multi-photon ionization and electron tunnel ionization) as well as their interactions with electron acceptors through associative electron capture, dissociative electron capture and electron detachment. Effects of different materials, sizes and shapes of semiconductor nano-crystals of quantum dots on photo-ionization will be investigated. In this work, the capability of structural identification, spatial resolution and selectivity of mass spectrometric imaging are expected to establish through chemical modifications on surfaces of quantum dots and photo-catalyzed coupling reactions as well as radical reactions. The proposed approach provides a new avenue for screening of lead compounds targeted to major receptor proteins that can also function as electron acceptors for electron-directed ionization and dissociation. It is expected to achieve high resolution mass spectrometric imaging of breast tissues and pathological classification of cancer cells in molecular levels. Early molecular biomarkers during disease progression from normal cells to cancerous cells and changes in micro-structural domains of tissues will be investigated.