中文摘要：

液体辅助表面解吸常压化学电离源（LA-DAPCI）通过电晕放电产生的初级离子和高密度带电液滴能够对样品表面的中性待测物进行解吸电离,该离子源具有较高的离子化效率,适合复杂基体样品的质谱成像研究。为了满足质谱成像对空间分辨率的要求,本实验通过优化离子源结构、萃取剂组成、萃取剂流量、载气流速、离子源的几何位置参数等实验条件,有效提高了LA-DAPCI源的空间分辨率（从（441±14）μm提高到（58±7）μm）。应用LA-DAPCI-MS/MS方法对罗丹明6G进行测定舱测限为0.01 ng/cm^2,实验结果令人满意,为其应用于复杂基体样品的质谱成像研究提供科学依据。

英文摘要：

Liquid-assisted surface desorption atmospheric pressure chemical ionization source（LA-DAPCI）technique shows good potential in complex matrix mass spectrometry imaging.Due to primary ions and high density charged droplets of solvent generated by corona discharge,analytes on sample surface are extracted and ionized efficiently.However,direct application of the DAPCI ionization for mass spectrometry imaging of complex matrix analytes usually tends to be challenging because of low spatial resolution.To resolve this problem,several ion source parameters and experiment conditions were optimized in the present work,including ion source configuration,chemical composition of the extraction solvent,geometry parameters,solvent flow rate and pressure of nebulizing gas.The results presented here confirmed that the spatial resolution of LA-DAPCI was improved（from（441±14） μm to（58±7） μm）.The proposed LA-DAPCI-MS/MS method was then successfully used to profile the distribution of Rhodamine 6G with a limit of detection of0.01 ng/cm^2.