Zhou P, Watson D G, Midgley J M
Department of Pharmaceutical Science, University of Strathclyde, Glasgow, UK.
J Chromatogr. 1993 Jul 23;617(1):11-8. doi: 10.1016/0378-4347(93)80415-z.
The gamma-glutamyl conjugates of p-octopamine and dopamine were identified unambiguously for the first time and quantified in a single cerebral ganglion or pleural plus pedal ganglia of the snail, Helix aspersa, by gas chromatography-negative-ion chemical ionisation mass spectrometry. A new method was used for synthesis of gamma-glutamylamine standards. The concentration of gamma-glutamyltyramine was found to be low in the tissues, therefore it was used as an internal standard. The gamma-glutamylamines were extracted with water and derivatised with pentafluoropropionic anhydride and trifluoroethanol. Under negative-ion chemical ionisation conditions, the trifluoroethyl and pentafluoropropionyl derivatives produced significant ions which were sufficiently abundant to be suitable for selective ion monitoring. The method had a limit of detection of ca. 80 pg of gamma-glutamyl conjugate per tissue and calibration curves were linear over the range examined.
首次明确鉴定出对章鱼胺和多巴胺的γ-谷氨酰共轭物，并通过气相色谱-负离子化学电离质谱法对蜗牛（Helix aspersa）的单个脑神经节或胸膜加足神经节中的这些共轭物进行了定量分析。采用一种新方法合成γ-谷氨酰胺标准品。发现组织中γ-谷氨酰酪胺的浓度较低，因此将其用作内标。γ-谷氨酰胺用水萃取，并用五氟丙酸酐和三氟乙醇进行衍生化。在负离子化学电离条件下，三氟乙基和五氟丙酰衍生物产生显著的离子，其丰度足以适用于选择性离子监测。该方法的检测限约为每个组织80 pg的γ-谷氨酰共轭物，在所研究的范围内校准曲线呈线性。
