Identification and quantification of myo-inositol hexakisphosphate in complex environmental matrices using ion chromatography and high-resolution mass spectrometry in comparison to 31P NMR spectroscopy
Identification and quantification of myo-inositol hexakisphosphate in complex environmental matrices using ion chromatography and high-resolution mass spectrometry in comparison to 31P NMR spectroscopy
复制标题
使用离子色谱法和高分辨率质谱法与 31P NMR 光谱法进行比较，对复杂环境基质中的肌醇六磷酸进行鉴定和定量
DOI：
10.1016/j.talanta.2019.120188
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发表时间：
2020
期刊：
影响因子：
6.1
通讯作者：
McIntyre C
中科院分区：
文献类型：
--
作者：
McIntyre C
肌醇六磷酸(myo-ip6，myo-ip6)是土壤和粪便中重要的有机磷化合物。土壤和粪便提取物中myo-IP6的测定通常用31P核磁共振波谱进行。这种方法在样品制备和仪器时间方面都很耗时，而且由于潜在地干扰共提取的P物种的共振，在鉴定和定量的准确性方面存在不确定性。相比之下，离子色谱(IC)与高分辨率质谱仪(HRMS)负离子、电喷雾电离(ESI)相结合，已被证明能够高度特异地鉴定从复杂混合物中分离出来的myo-IP6。本文应用离子对映体和电喷雾质谱(ESI-HRMS)对NaOH-EDTA萃取法从土壤和粪便中分离的myo-IP6进行了鉴定和定量，并基于离子对映体离子对其进行了定量。对IC淋洗液的ESI-HRMS分析明确证实了从土壤提取物中鉴定出myo-IP6。IC仪器的离子抑制池提供了分离的分析物，不含干扰ESI的离子成分。通过比较在提取前添加和不添加正品myo-IP6的土壤萃取物的光谱，在核磁共振中鉴定了Themyo-IP6。IC分析和核磁共振分析中标准加入法的定量结果具有很好的相关性(r = 0.955)。31P核磁共振仪检测Myo-IP6的检测下限为0.70 mg kg−1，定量下限为2.1 mg kg−1，与 和GT比较， 10 mg kg−1LOD更灵敏、快速、可靠。
Myo-inositol hexakisphosphate, or phytic acid, (myo-IP6) is a key organic phosphorus (P) compound in soils and manures. Determinations ofmyo-IP6 in soils and manure extracts are frequently performed by31P NMR spectroscopy. This approach is time-consuming in terms of both sample preparation and instrument time, with uncertainties existing in relation to accuracy of identification and quantification due to potentially interfering resonances from co-extracted P species. In contrast, ion chromatography (IC) in combination with high-resolution mass spectrometry (HRMS) negative ion, electrospray ionisation (ESI) has been shown to enable highly specific identifications ofmyo-IP6 isolated from complex mixtures. In this paper, IC and ESI-HRMS were applied to the identification and the quantification ofmyo-IP6 isolated from soils and manures using NaOH-EDTA extraction, and quantifications based on IC. ESI-HRMS analysis of eluate trapped from IC unequivocally confirmed identification ofmyo-IP6 from a soil extract. The ion suppression cell of the IC instrument provides isolates of the analyte free of ionic components that would interfere with ESI. Themyo-IP6 was identified in the NMR by comparing spectra of extracts of soils with and without authenticmyo-IP6 “spiked” prior to extraction. Comparison of quantificationviastandard addition in IC and NMR analysis gave good correlation (r = 0.955). IC with ESI-HRMS was found to be more sensitive, rapid and reliable for the identification and quantification ofmyo-IP6 with a limit of detection (LOD) of 0.7 mg kg−1and limit of quantification (LOQ) of 2.1 mg kg−1using IC versus > 10 mg kg−1LOD using31P NMR.