Spin traps, like 5,5-dimethyl-1-pyrroline N-oxide (DMPO), are commonly used to identify radicals formed in numerous chemical and biological systems, many of which contain metal-ion complexes. In this study, continuous wave electron paramagnetic resonance and hyperfine spectroscopy are used to prove the equatorial ligation of DMPO(-derived) molecules to Cu(II), even in the presence of competing nitrogen bases. The experimental data are corroborated with density functional theory calculations. It is shown that ¹⁴N HYSCORE can be used as a fingerprint method to reveal the coordination of DMPO(-derived) molecules to Cu(II), an interaction that might influence the outcome of spin-trapping experiments and consequently the conclusion drawn on the mechanism under study.

自旋阱，例如5,5-二甲基-1-吡咯啉N-氧化物（DMPO），通常用于鉴定在许多化学和生物系统中形成的自由基，其中许多含有金属离子络合物。在这项研究中，连续波电子顺磁共振和超精细光谱被用来证明DMPO（派生）分子与Cu（II）的赤道连接，即使在存在竞争性氮碱基的情况下。实验数据得到密度泛函理论计算的证实。结果表明，¹⁴ N HYSCORE可以用作指纹法揭示DMPO（衍生）分子与Cu（II）的配位作用，这种相互作用可能会影响自旋俘获实验的结果，并因此得出结论。机制正在研究中。