Electron paramagnetic resonance (EPR) spectroscopy has emerged as a fast, reliable, non-invasive and sensitive method to determine the distribution, localization and reactivity of labelled ingredients in micro-heterogeneous systems. However, the commercially available probe molecules are very limited. In the present work, five new nitroxide [(4-hydroxy-2, 2, 6, 6-tetramethylpiperidin-1-oxyl (TEMPOL)] derivatives (1b–5b) of diacetyl tartaric acid esters of monoglycerides (DATEM) (1a–5a), a widely used food emulsifier, were synthesized under Steglich conditions and characterized by MS (mass-spectrometry), FT-IR (Fourier-transform infrared spectroscopy), EPR, NMR (nuclear magnetic resonance spectroscopy), fluorescence spectroscopy, and DSC (differential scanning calorimetry) analysis. Phase partitioning studies proved that the new spin labels are adequately capable of describing the localizations and partitioning of the corresponding DATEM in multi-phase systems. Findings disclosed in this work will provide new knowledge on ingredient reactivity and localization in multi-phase systems; which is vital to aid the design of more efficient delivery systems for bioactive compounds.

电子顺磁共振（EPR）光谱学已成为一种快速，可靠，非侵入性和灵敏的方法，可用于确定微异构系统中标记成分的分布，定位和反应性。但是，可商购的探针分子非常有限。另外，在本工作中，五个新氮氧化物[（4-羟基-2，2，6,6四甲基哌啶1-氧基（TEMPOL）]衍生物（1B - 5B单甘油酯（DATEM）（的二乙酰酒石酸酯的）1A - 5a），一种广泛使用的食品乳化剂，在Steglich条件下合成，并通过MS（质谱），FT-IR（傅立叶变换红外光谱），EPR，NMR（核磁共振光谱），荧光光谱和DSC（差示扫描量热法）分析。相分配研究证明，新的自旋标记物足以描述多相系统中相应DATEM的定位和分配。这项工作中揭示的发现将提供有关多相系统中成分反应性和定位的新知识；这对于帮助设计更高效的生物活性化合物输送系统至关重要。