Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
Rapid Commun Mass Spectrom. 2011 Apr 30;25(8):1043-50. doi: 10.1002/rcm.4954. Epub 2011 Mar 29.
A procedure to prepare and purify adducts of formaldehyde (FA) to the N-terminus of peptides was developed. FA-VHLTPEEK and FA-VLSPADK were produced with purities >95% upon incubation of the peptides with FA in phosphate-buffered saline (PBS) at a pH level of 7.4. The peptides were purified by preparative liquid chromatography and were characterized by their retention times in liquid chromatography, their fragmentation patterns obtained by tandem mass spectrometry, and their accurate mass and nuclear magnetic resonance measurements. This is the first time an imidazolidone-type structure has been reported for FA adducts. The same peptides were identified in tryptic digests of human hemoglobin incubated with FA at physiological conditions and in human hemoglobin specimens. These peptides are suitable for use as calibrators for the quantitative assessment of internal exposure to FA.
开发了一种在肽的 N 末端制备和纯化甲醛（FA）加合物的方法。在 pH 值为 7.4 的磷酸盐缓冲盐水（PBS）中，将 FA 与肽孵育，可得到纯度>95%的 FA-VHLTPEEK 和 FA-VLSPADK。通过制备液相色谱法对肽进行纯化，并通过液相色谱的保留时间、串联质谱获得的碎片模式以及精确质量和核磁共振测量对其进行表征。这是首次报道 FA 加合物的亚氨二唑酮型结构。在生理条件下 FA 与人血红蛋白孵育的胰蛋白酶消化物以及人血红蛋白标本中均鉴定出相同的肽。这些肽适合用作定量评估内暴露于 FA 的校准物。
