The formation mechanisms of singly and multiply charged organophosphate metabolites by electrospray ionization (ESI) and their gas phase stabilities were investigated. Metabolites containing multiple phosphate groups, such as adenosine 5'-diphosphate (ADP), adenosine 5'-triphosphate (ATP), and D-myo-inositol-1,4,5-triphosphate (IP₃) were observed as doubly deprotonated ions by negative-ion ESI mass spectrometry. Organophosphates with multiple negative charges were found to be unstable and often underwent loss of PO₃ ^–, although singly deprotonated analytes were stable. The presence of fragments due to the loss of PO₃ ^– in the negative-ion ESI mass spectra could result in the misinterpretation of analytical results. In contrast to ESI, matrix-assisted laser desorption ionization (MALDI) produced singly charged organophosphate metabolites with no associated fragmentation, since the singly charged anions are stable. The stability of an organophosphate metabolite in the gas phase strongly depends on its charge state. The fragmentations of multiply charged organophosphates were also investigated in detail through density functional theory calculations.

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研究了电喷雾电离（ESI）形成的单电荷和多电荷有机磷酸酯代谢物的形成机理及其气相稳定性。观察到含有多个磷酸基团的代谢物，例如腺苷5'-二磷酸（ADP），腺苷5'-三磷酸（ATP）和D-肌醇-1,4,5-三磷酸（IP ₃）为双去质子化离子。通过负离子ESI质谱分析。与多个负电荷有机磷被认为是PO的不稳定，经常例行损失₃ ^- ，虽然单独去质子分析物是稳定的。由于丢失了PO ₃ 而导致碎片的存在^–负离子ESI质谱图中的质谱图可能会导致对分析结果的误解。与ESI相比，基质辅助激光解吸电离（MALDI）可以产生单电荷的有机磷酸酯代谢物，而没有相关的碎片，因为单电荷的阴离子是稳定的。气相中有机磷酸酯代谢物的稳定性强烈取决于其电荷状态。还通过密度泛函理论计算详细研究了多电荷有机磷酸酯的碎片。

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