Ozonolysis of alkene functional groups is a type of highly specific and effective chemical reaction, which has found increasing applications in structural analysis of unsaturated lipids via coupling with mass spectrometry (MS). In this work, we utilized a low-pressure mercury lamp (6 W) to initiate ozonolysis inside electrospray ionization (ESI) sources. By placing the lamp near a nanoESI emitter that partially transmits 185 nm ultraviolet (UV) emission from the lamp, dissolved dioxygen in the spray solution was converted into ozone, which subsequently cleaved the double bonds within fatty acyls of lipids. Solvent conditions, such as presence of water and acid solution pH, were found to be critical in optimizing ozonolysis yields. Fast (on seconds time scale) and efficient (50%–100% yield) ozonolysis was achieved for model unsaturated phospholipids and fatty acids with UV lamp-induced ozonolysis incorporated on a static and an infusion nanoESI source. The method was able to differentiate double bond location isomers and identify the geometry of the double bond based on yield. The analytical utility of UV lamp-induced ozonolysis was further demonstrated by implementation on a liquid chromatography (LC)-MS platform. Ozonolysis was effected in a flow microreactor that was made from ozone permeable tubing, so that ambient ozone produced by the lamp irradiation could diffuse into the reactor and induce online ozonolysis post-LC separation and before ESI-MS.

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烯烃官能团的臭氧分解是一种高度特异性和有效的化学反应，通过与质谱联用（MS）已发现其在不饱和脂质的结构分析中的应用越来越广泛。在这项工作中，我们利用低压汞灯（6 W）在电喷雾电离（ESI）源内部引发臭氧分解。通过将灯放置在nanoESI发射器附近，该发射器会部分透射灯的185 nm紫外线（UV）发射，喷涂溶液中溶解的双氧会转化为臭氧，随后会裂解脂质的脂肪酰基中的双键。发现溶剂条件，例如水和酸溶液pH的存在，对于优化臭氧分解产率至关重要。通过在静态和注入nanoESI光源上结合UV灯诱导的臭氧分解，可对模型不饱和磷脂和脂肪酸进行快速（以秒为单位的时间）和有效（50％–100％的产率）的臭氧分解。该方法能够区分双键位置异构体，并基于产率鉴定双键的几何形状。通过在液相色谱（LC）-MS平台上的实施进一步证明了UV灯诱导的臭氧分解的分析效用。臭氧分解是在由臭氧可渗透管制成的流动微反应器中进行的，因此，灯照射产生的环境臭氧可扩散到反应器中，并在LC分离后和ESI-MS之前引起在线臭氧分解。该方法能够区分双键位置异构体，并基于产率鉴定双键的几何形状。通过在液相色谱（LC）-MS平台上的实施进一步证明了UV灯诱导的臭氧分解的分析效用。臭氧分解是在由臭氧可渗透管制成的流动微反应器中进行的，因此，灯照射产生的环境臭氧可扩散到反应器中，并在LC分离后和ESI-MS之前引起在线臭氧分解。该方法能够区分双键位置异构体，并基于产率鉴定双键的几何形状。通过在液相色谱（LC）-MS平台上的实施进一步证明了UV灯诱导的臭氧分解的分析效用。臭氧分解是在由臭氧可渗透管制成的流动微反应器中进行的，因此，灯照射产生的环境臭氧可扩散到反应器中，并在LC分离后和ESI-MS之前引起在线臭氧分解。

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