title: Determination of dopamine, serotonin, biosynthesis precursors and metabolites in rat brain microdialysates by ultrasonic-assisted in situ derivatization-dispersive liquid-liquid microextraction coupled with UHPLC-MS/MS.
abstract: This paper, for the first time, reported a simple, rapid, sensitive and environmental friendly ultrasonic-assisted in situ derivatization-dispersive liquid-liquid microextraction (in situ UAD-DLLME) method followed by ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for the simultaneous determination of dopamine (DA), serotonin (5-HT) and their biosynthesis precursors and metabolites in rat brain microdialysates. In this work, a commercial reagent, Lissamine rhodamine B sulfonylchloride (LRSC), was proposed as a derivatization reagent. The ionization efficiency of neurotransmitters was greatly enhanced through the introduction of a permanent charged moiety of LRSC into their derivatives during electrospray ionization MS (ESI-MS) analysis. Parameters of in situ UAD-DLLME and UHPLC-MS/MS conditions were all optimized in detail. The optimum conditions of in situ UAD-DLLME were found to be as follows: a mixture of 150μL of acetonitrile (dispersant) containing LRSC (derivatization reagents) and 50μL of low toxic bromobenzene (extractant) was rapidly injected into an aqueous sample containing 30μL of microdialysate and 800μL of NaHCO3-Na2CO3buffer solution (pH 10.5) at 37°C. After ultrasonication for 3min and centrifuging for 2min, the sedimented phase was conveniently injected for UHPLC-MS/MS analysis. Under the optimized conditions, good linearity was observed with the limits of detection (LODs, S/N>3) and limits of quantification (LOQs, S/N>10) in the range of 0.002-0.008 and 0.015-0.040nmol/L, respectively. Meanwhile, it also brought good results of precision (3.2-13.0%, peak area RSDs %), accuracy (86.4-112%), recovery (73.9-105%), matrix effect (86.2-105%), and stability (3.1-8.8%, peak area RSDs %). The developed method was successfully applied for the simultaneous determination of multiple neurotransmitters, their precursors and metabolites in brain microdialysates of normal and L-DOPA induced dyskinesias (LID) rats.
authors: Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165 PR China.
authors: Na
authors: N
authors: Wei
authors: Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165 PR China. Electronic address: xianenzhao@163.com.
authors: Xian-En
authors: XE
authors: Zhao
authors: Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165 PR China.
authors: Shuyun
authors: S
authors: Zhu
authors: Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165 PR China.
authors: Yongrui
authors: Y
authors: He
authors: Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165 PR China.
authors: Longfang
authors: L
authors: Zheng
authors: Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165 PR China.
authors: Guang
authors: G
authors: Chen
authors: Shandong Provincial Key Laboratory of Life-Organic Analysis & Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165 PR China. Electronic address: jmyou6304@163.com.
authors: Jinmao
authors: J
authors: You
authors: National Center for Mass Spectrometry in Changchun & Key Laboratory for Traditional Chinese Medicine Chemistry and Mass Spectrometry of Jilin Province, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin, 130022 PR China.
authors: Shu
authors: S
authors: Liu
authors: National Center for Mass Spectrometry in Changchun & Key Laboratory for Traditional Chinese Medicine Chemistry and Mass Spectrometry of Jilin Province, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin, 130022 PR China. Electronic address: liuzq@ciac.ac.cn.
authors: Zhiqiang
authors: Z
authors: Liu
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis; D000818:Animals; D001921:Brain / Q000378:metabolism; D001923:Brain Chemistry; D002851:Chromatography, High Pressure Liquid; D004298:Dopamine / Q000032:analysis*; D020820:Dyskinesias / Q000378:metabolism; D004837:Epinephrine / Q000032:analysis; D006897:Hydroxyindoleacetic Acid / Q000032:analysis; D007980:Levodopa / Q000032:analysis; D059627:Liquid Phase Microextraction; D008297:Male; D009638:Norepinephrine / Q000032:analysis; D017207:Rats, Sprague-Dawley; D012235:Rhodamines / Q000737:chemistry; D012701:Serotonin / Q000032:analysis*; D053719:Tandem Mass Spectrometry; D014364:Tryptophan / Q000032:analysis; D014465:Ultrasonics
chemical_list: D012235:Rhodamines; D015102:3,4-Dihydroxyphenylacetic Acid; D012701:Serotonin; D007980:Levodopa; D006897:Hydroxyindoleacetic Acid; C027305:Lissamine Rhodamine B sulfonyl chloride; D014364:Tryptophan; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine
keywords: Dispersive liquid–liquid microextraction; In situ derivatization; In vivo microdialysis; Neurotransmitter; Parkinson's disease; Ultra high performance liquid chromatography-tandem mass spectrometry