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Ding X, Liu C, Yu W, Liu Z. Magnetic ionic liquid-based liquid-liquid microextraction followed by ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry for simultaneous determination of neurotransmitters in human cerebrospinal fluid and plasma. Talanta 2023; 262:124690. [PMID: 37229812 DOI: 10.1016/j.talanta.2023.124690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 05/04/2023] [Accepted: 05/17/2023] [Indexed: 05/27/2023]
Abstract
A green, efficient and easy sample pretreatment method of magnetic ionic liquid-based liquid-liquid microextraction (MIL-based LLME) combined with a sensitive, rapid and precise analytical method of ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-QqQ/MS2) was developed to simultaneously - determining of neurotransmitters (NTs) in biosamples. Two magnetic ionic liquids (MILs), [P6,6,6,14]3[GdCl6] and [P6,6,6,14]2[CoCl4] tested, and the latter was selected as the extraction solvent due to its advantages of visual recognition, paramagnetic behavior and higher extraction efficiency. Facile magnetic separation of MIL containing analytes from matrix was realized by applying external magnetic field without rather than centrifugation. Experimental parameters that would influence the extraction efficiency, including type and amount of MIL, extraction time, speed of the vortex process, salt concentration, and environmental pH, were optimized obtained. The proposed method was successfully applied to the simultaneous extraction and determination of 20 NTs in human cerebrospinal fluid and plasma samples. Excellent analytical performance indicates the broad potential of this method for clinical diagnosis and therapy of neurological diseases.
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Affiliation(s)
- Xiangdong Ding
- Department of Plastic and reconstructive Microsurgery, China-Japan Union Hospital, Jilin University, Xiantai Street 126, Changchun, 130033, PR China
| | - Chao Liu
- Department of Medical Cosmetology, South China Hospital, Medical School, Shenzhen University, Shenzhen, 518116, PR China
| | - Wei Yu
- Department of Plastic and reconstructive Microsurgery, China-Japan Union Hospital, Jilin University, Xiantai Street 126, Changchun, 130033, PR China.
| | - Zhongling Liu
- China-Japan Union Hospital, Jilin University, Xiantai Street 126, Changchun, 130033, PR China.
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2
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Yao J, Lu H, Wang Z, Wang T, Fang F, Wang J, Yu J, Gao R. A sensitive method for the determination of the gender difference of neuroactive metabolites in tryptophan and dopamine pathways in mouse serum and brain by UHPLC-MS/MS. J Chromatogr B Analyt Technol Biomed Life Sci 2018; 1093-1094:91-99. [PMID: 30005419 DOI: 10.1016/j.jchromb.2018.06.054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 06/20/2018] [Accepted: 06/24/2018] [Indexed: 12/21/2022]
Abstract
Tryptophan (TRP) and dopamine (DA) pathways are of great importance for their related pathology and physiology. In the present study, a new reliable and sensitive analytical method was developed and validated for 12 neuroactive metabolites in TRP and DA pathways in mouse serum and brain by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method exhibited good sensitivity as the lower limit of detections ranged from 0.10 to 0.50 ng/ml and the lower limit of quantifications ranged from 0.20 to 2.00 ng/ml by derivatization with dansyl chloride (DNS-Cl) following solid phase extraction (SPE) on C18 cartridges. Good linearity (R2 > 0.99), intra-day precision (<9.8% in serum and <8.8% in brain), inter-day precision (<8.9% in serum and <8.5% in brain) and accuracy (90.3%-110.3% in serum and 86.5%-114.0% in brain) were obtained. The method was successfully applied in measuring 12 neuroactive metabolites in TRP and DA pathways in serum and brain samples of male and female mice to explore the differences between genders. As a result, DA and the turnover of DA to 3,4-dihydroxyphenylacetic acid (DOPAC), 5-hydroxtryptamine (5-HT) to TRP and 5-hydroxyindole acetic acid (5-HIAA) to 5-HT in the serum and norepinephrine (NE) in the brain were significantly different between genders.
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Affiliation(s)
- Jiaxi Yao
- Department of Hygienic Analysis and Detection, The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China
| | - Haihua Lu
- Department of Hygienic Analysis and Detection, The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China
| | - Zhonghe Wang
- Department of Hygienic Analysis and Detection, The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China
| | - Tingwei Wang
- Department of Toxicology, Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China
| | - Fangfang Fang
- Department of Toxicology, Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China
| | - Jun Wang
- Department of Toxicology, Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China
| | - Jing Yu
- Department of Hygienic Analysis and Detection, The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China.
| | - Rong Gao
- Department of Hygienic Analysis and Detection, The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, No. 101 Longmian Avenue, Nanjing 211166, China.
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Megha K, Deshmukh PS, Ravi AK, Tripathi AK, Abegaonkar MP, Banerjee BD. Effect of Low-Intensity Microwave Radiation on Monoamine Neurotransmitters and Their Key Regulating Enzymes in Rat Brain. Cell Biochem Biophys 2017; 73:93-100. [PMID: 25672490 DOI: 10.1007/s12013-015-0576-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The increasing use of wireless communication devices has raised major concerns towards deleterious effects of microwave radiation on human health. The aim of the study was to demonstrate the effect of low-intensity microwave radiation on levels of monoamine neurotransmitters and gene expression of their key regulating enzymes in brain of Fischer rats. Animals were exposed to 900 MHz and 1800 MHz microwave radiation for 30 days (2 h/day, 5 days/week) with respective specific absorption rates as 5.953 × 10(-4) and 5.835 × 10(-4) W/kg. The levels of monoamine neurotransmitters viz. dopamine (DA), norepinephrine (NE), epinephrine (E) and serotonin (5-HT) were detected using LC-MS/MS in hippocampus of all experimental animals. In addition, mRNA expression of key regulating enzymes for these neurotransmitters viz. tyrosine hydroxylase (TH) (for DA, NE and E) and tryptophan hydroxylase (TPH1 and TPH2) (for serotonin) was also estimated. Results showed significant reduction in levels of DA, NE, E and 5-HT in hippocampus of microwave-exposed animals in comparison with sham-exposed (control) animals. In addition, significant downregulation in mRNA expression of TH, TPH1 and TPH2 was also observed in microwave-exposed animals (p < 0.05). In conclusion, the results indicate that low-intensity microwave radiation may cause learning and memory disturbances by altering levels of brain monoamine neurotransmitters at mRNA and protein levels.
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Affiliation(s)
- Kanu Megha
- Environmental Biochemistry and Molecular Biology Laboratory, Department of Biochemistry, University College of Medical Sciences & G.T.B. Hospital (University of Delhi), Dilshad Garden, New Delhi, 110095, India
| | - Pravin S Deshmukh
- Environmental Biochemistry and Molecular Biology Laboratory, Department of Biochemistry, University College of Medical Sciences & G.T.B. Hospital (University of Delhi), Dilshad Garden, New Delhi, 110095, India
| | - Alok K Ravi
- Dr. R. P. Centre for Ophthalmic Sciences, Department of Ocular Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | - Ashok K Tripathi
- Environmental Biochemistry and Molecular Biology Laboratory, Department of Biochemistry, University College of Medical Sciences & G.T.B. Hospital (University of Delhi), Dilshad Garden, New Delhi, 110095, India
| | - Mahesh P Abegaonkar
- Centre for Applied Research in Electronics (CARE), Indian Institute of Technology, Hauz Khas, New Delhi, 110016, India
| | - Basu D Banerjee
- Environmental Biochemistry and Molecular Biology Laboratory, Department of Biochemistry, University College of Medical Sciences & G.T.B. Hospital (University of Delhi), Dilshad Garden, New Delhi, 110095, India.
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Shahbazi-Gahrouei D, Shiri L, Alaei H, Naghdi N. The effect of continuous ELF-MFs on the level of 5-HIAA in the raphe nucleus of the rat. JOURNAL OF RADIATION RESEARCH 2016; 57:127-32. [PMID: 26811259 PMCID: PMC4795953 DOI: 10.1093/jrr/rrv093] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 10/03/2015] [Accepted: 10/19/2015] [Indexed: 06/05/2023]
Abstract
The aim of this study was to investigate the effect of continuous extremely low frequency magnetic fields (ELF-MFs) with a frequency of 10 Hz and an intensity of 690-720 μT on the level of 5-hydroxyindolacetic acid (5-HIAA) in adult male Wistar rats. A total of 24 adult Wistar male rats were used, and after exposure with an ELF-MF for 15 successive days, all rats in each test were anesthetized with chloral hydrate. Then, they were placed in a stereotaxic frame for surgery and a microdialysis process. Dialysate samples were analyzed to measure the amount of 5-HIAA by high performance liquid chromatography (HPLC) using electrochemical detection. Results showed that ELF-MF exposure for 15 days, 1 h daily, was not effective in altering the level of 5-HIAA. However, ELF-MF exposure for 15 days, 3 h daily, decreased the level of the 5-HIAA in the raphe nucleus. It can be concluded that ELF-MFs affect the serotonergic system and may be used to treat nervous system diseases. This study is an initial step towards helping cure depression using ELF-MFs.
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Affiliation(s)
- Daryoush Shahbazi-Gahrouei
- Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Leila Shiri
- Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hojjatollah Alaei
- Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Naser Naghdi
- Department of Physiology, Pasteur Institute, Tehran, Iran
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He B, Bi K, Jia Y, Wang J, Lv C, Liu R, Zhao L, Xu H, Chen X, Li Q. Rapid analysis of neurotransmitters in rat brain using ultra-fast liquid chromatography and tandem mass spectrometry: application to a comparative study in normal and insomnic rats. JOURNAL OF MASS SPECTROMETRY : JMS 2013; 48:969-78. [PMID: 23893645 DOI: 10.1002/jms.3243] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 05/22/2013] [Accepted: 06/03/2013] [Indexed: 05/24/2023]
Abstract
Neurotransmitters and their metabolites in central nervous system were known to play a significant role in sedation and hypnosis. A rapid and sensitive UFLC-MS/MS method for simultaneous determination of serotonin, 5-hydroxyindole acetic acid (5-HIAA), tryptophan (Try), dopamine (DA), norepinephrine (NE), γ-aminobutyric acid (GABA), glutamic acid (Glu) and acetylcholine (Ach) in rat brain without derivatization, ion-pairing reagent or pre-concentration was developed. Analytes and IS were separated on a Inertsil ODS-EP column (150 mm × 4.6 mm, 5 µm particles) and analyzed in a single chromatographic run in less than 9.0 min, using gradient elution with the mobile phase consisting of methanol and 0.01% acetic acid in water at a flow rate of 1.2 ml min(-1) . The detection of the analytes was performed on 4000Q UFLC-MS/MS system with turbo ion spray source in positive ion and multiple reaction monitoring mode. The developed method provided excellent linear calibration curves for the assay of analytes (R(2) ≥ 0.9915). Limits of quantification were in the range of 1.0 ng ml(-1) to 1.0 µg ml(-1) for the analytes in rat brain. Intra- and inter-day precision and accuracy of analytes were well within acceptance criteria (15%). Mean extraction recoveries of analytes and IS from rat brain were all more than 80.0%. Furthermore, the validated method was successfully applied to comparing profiles of analytes in normal and insomnic rat brains. Results indicated that there were statistically significant differences for serotonin, 5-HIAA, DA, NE, Glu and Ach, but no significant difference for Try and GABA between two groups.
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Affiliation(s)
- Bosai He
- Laboratory co-established by the province and the state, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, 110016, China
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Greco S, Danysz W, Zivkovic A, Gross R, Stark H. Microdialysate analysis of monoamine neurotransmitters—A versatile and sensitive LC–MS/MS method. Anal Chim Acta 2013; 771:65-72. [DOI: 10.1016/j.aca.2013.02.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 01/24/2013] [Accepted: 02/02/2013] [Indexed: 02/03/2023]
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González RR, Fernández RF, Vidal JLM, Frenich AG, Pérez MLG. Development and validation of an ultra-high performance liquid chromatography-tandem mass-spectrometry (UHPLC-MS/MS) method for the simultaneous determination of neurotransmitters in rat brain samples. J Neurosci Methods 2011; 198:187-94. [PMID: 21459108 DOI: 10.1016/j.jneumeth.2011.03.023] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 03/25/2011] [Accepted: 03/26/2011] [Indexed: 10/18/2022]
Abstract
A simple method for the simultaneous determination of glutamate, γ-aminobutyric acid (GABA), choline, acetylcholine, dopamine, 5-hydroxyindole-3-acetic (5-HIAA), serotonin, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) was developed by using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). These compounds are analysed in a single chromatographic run in less than 8 min, adding heptafluorobutyric acid (HFBA) in the mobile phase to improve the separation of the selected neurotransmitters. The analytes were detected using electrospray ionization (ESI)-MS/MS in positive mode with multiple reaction monitoring (MRM). Good linearity was obtained (R² > 0.98) and the intra and inter-day precision of the method (expressed as relative standard deviation) were lower than 26%. Limits of quantification were lower than 2.440 μg/g of brain in all the cases, allowing the sensitive determination of these compounds in rat brain extracts. Therefore, the method was successfully applied for the quantitative determination of neurotransmitters in several rat brain regions (prefrontal cortex, striatum, nucleus accumbens and amygdala), detecting glutamate, GABA and choline at concentrations higher than 1000 μg/g, 30 μg/g and 100 μg/g respectively, whereas the other compounds were found at lower concentrations.
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Affiliation(s)
- Roberto Romero González
- Research Group "Analytical Chemistry of Contaminants", Department of Analytical Chemistry, Almeria University, 04071 Almeria, Spain
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Antidepressant-like effects of echo-planar magnetic resonance imaging in mice determined using the forced swimming test. Brain Res 2008; 1236:194-9. [PMID: 18755160 DOI: 10.1016/j.brainres.2008.08.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Revised: 08/06/2008] [Accepted: 08/08/2008] [Indexed: 02/06/2023]
Abstract
Echo-planar magnetic resonance imaging (EP-MRI), which is novel variant of MRI, is thought to have antidepressant properties in humans and animal models. Using the forced swimming test (FST), we investigated which monoaminergic system in mice is affected by EP-MRI. The short- and long-term effects of EP-MRI on immobility time in the FST and motor activity within a locomotor activity cage were examined. Two groups of mice underwent 20 min of EP-MRI in an MR scanner (Siemens, 1.5 T Symphony) either 23.5 or 1 h before the start of the second session of the FST. In both groups, the immobility duration in the FST was reduced, similar to effective antidepressant drug treatments. Climbing behavior in the 1-h group and swimming behavior in the 23.5-h group increased significantly, similar to that seen after the administration of desipramine (a noradrenaline reuptake inhibitor) and sertraline (a selective serotonin reuptake inhibitor), respectively. The findings support the hypothesis that EP-MRI has an antidepressant-like effect. We suggest that the antidepressant-like effect begins in the early period with noradrenaline systems and is maintained in the late period with serotonin systems.
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Sasaki T, Fukushima T, Ohishi M, Toyo'oka T. Development of a 6-hydroxychroman-based derivatization reagent: application to the analysis of 5-hydroxytryptamine and catecholamines by using high-performance liquid chromatography with electrochemical detection. Biomed Chromatogr 2008; 22:888-99. [DOI: 10.1002/bmc.1007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Zhang X, Rauch A, Lee H, Xiao H, Rainer G, Logothetis NK. Capillary hydrophilic interaction chromatography/mass spectrometry for simultaneous determination of multiple neurotransmitters in primate cerebral cortex. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:3621-3628. [PMID: 17939159 DOI: 10.1002/rcm.3251] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A diverse array of neurotransmitters and neuromodulators control and affect brain function. A profound understanding of the signaling pathways and the neural circuits underlying behavior is therefore likely to require the tracking of concentration changes of active neurochemicals. In the present study, we demonstrate the feasibility of a method allowing the simultaneous determination of the concentrations of six neurotransmitters: acetylcholine, serotonin, dopamine, gamma-aminobutyric acid (GABA), glutamate and aspartate, in the extracellular brain fluid (EBF). We used hydrophilic interaction chromatography (HILIC) coupled to tandem mass spectrometry (MS/MS) to analyze the EBF from the monkey brain. A push-pull sampling method was used to collect EBF from the prefrontal cortex (PFC) of conscious monkeys at flow rates in the range of low nL/min. The detection limits of acetylcholine, serotonin, dopamine, GABA, glutamate and aspartate were 0.015, 0.15, 0.3, 1.2, 6 and 15 femtomoles, respectively, allowing us to quantitatively determine the concentrations of these six neurotransmitters simultaneously from 500 nL in vivo samples. We conclude that HILIC/MS/MS combined with the push-pull sampling method represents a sensitive technique for simultaneous monitoring of neurotransmitters from EBF samples.
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Affiliation(s)
- Xiaozhe Zhang
- Max Plank Institute for Biological Cybernetics, 72076 Tubingen, Germany.
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Yoshitake T, Kehr J, Yoshitake S, Fujino K, Nohta H, Yamaguchi M. Determination of serotonin, noradrenaline, dopamine and their metabolites in rat brain extracts and microdialysis samples by column liquid chromatography with fluorescence detection following derivatization with benzylamine and 1,2-diphenylethylenediamine. J Chromatogr B Analyt Technol Biomed Life Sci 2004; 807:177-83. [PMID: 15203027 DOI: 10.1016/j.jchromb.2004.03.069] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2004] [Revised: 03/24/2004] [Accepted: 03/25/2004] [Indexed: 11/24/2022]
Abstract
A highly selective and sensitive column liquid chromatographic method for fluorescence determination of serotonin (5-HT), dopamine (DA), noradrenaline (NA) and their related metabolites 5-hydroxyindole-3-acetic acid (5-HIAA) and 3,4-dihydroxyphenylacetic acid (DOPAC) following derivatization with benzylamine and 1,2-diphenylethylenediamine (DPE) is described. The monoamines and the metabolites (20 microl samples) were derivatized in a two-step reaction, initiated with 20 microl of 0.3M benzylamine in 0.3M 3-cyclohexylaminopropanesulfonic acid (CAPS) buffer (pH 10.0), (for 5-HT, 5-HIAA, 2 min, 24 degrees C) and followed by 20 microl of 0.1M DPE in 0.3M glycine buffer (pH 10.0), (for DA, NA, DOPAC, 20 min, 50 degrees C). Both reagents contained 0.02 M potassium hexacyanoferrate(III) and 50% (v/v) methanol. The resulting highly fluorescent and stable benzoxazole derivatives were isocratically separated on a reversed-phase column (150 mm x 1.5 mm i.d., packed with C18 silica, 5 microm) within 45 min. Using fluorescence detection at ex. and em. wavelengths of 345 and 480 nm, respectively, the detection limit (signal-to-noise ratio of 3) for 5-HT, DA, NA, 5-HIAA, L-DOPA and DOPAC ranged between 0.08 and 5.65 fmol per 20-microl injection (12-847.5 pM in standard solution). The concentrations of monoamines (expressed in microg/g wet weight, mean +/- S.E.M., n=5) in tissue extracts from the rat striatum were: 0.45+/-0.05 (5-HT), 4.27+/-0.08 (DA), 0.27+/-0.04 (NA), 0.55+/-0.06 (5-HIAA), 1.26+/-0.16 (L-DOPA) and 1.62+/-0.11 (DOPAC). Microdialysis samples were collected in 20 min intervals from the probes implanted in the striatum of awake rats. The basal monoamine levels (in fmol/20 microl, mean +/- S.E.M., n=5) in the dialysates were: 4.0+/-0.7 (5-HT), 78.4+/-9.1 (DA), 6.4+/-0.8 (NA), 785.5+/-64.5 (5-HIAA) and 5504.5+/-136.5 (DOPAC). It is concluded that the new fluorescence derivatization protocol provides an excellent means for simultaneous determination of all three monoamines both in the complex samples (e.g. brain homogenates) and also at trace levels, such as those found in the microdialysis samples.
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Affiliation(s)
- Takashi Yoshitake
- Department of Neuroscience, Karolinska Institutet, S-171 77 Stockholm, Sweden
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Cao XN, Lin L, Zhou YY, Zhang W, Shi GY, Yamamoto K, Jin LT. Study of the interaction of 6-mercaptopurine with protein by microdialysis coupled with LC and electrochemical detection based on functionalized multi-wall carbon nanotubes modified electrode. J Pharm Biomed Anal 2003; 32:505-12. [PMID: 14565555 DOI: 10.1016/s0731-7085(03)00158-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Microdialysis sampling coupled with liquid chromatography and electrochemical detection (LC-ECD) was developed and applied to study the interaction of 6-Mercaptopurine (6-MP) with bovine serum albumin (BSA). In the LC-ECD, the multi-wall carbon nanotubes fuctionalized with carboxylic groups modified electrode (MWNT-COOH CME) was used as the working electrode for the determination of 6-MP. The results indicated that this chemically modified electrode (CME) exhibited efficiently electrocatalytic oxidation for 6-MP with relatively high sensitivity, stability and long-life. The peak currents of 6-MP were linear to its concentrations ranging from 4.0 x 10(-7) to 1.0 x 10(-4) mol l(-1) with the calculated detection limit (S/N = 3) of 2.0 x 10(-7) mol l(-1). The method had been successfully applied to assess the association constant (K) and the number of the binding sites (n) on a BSA molecular, which calculated by Scatchard equation, were 3.97 x 10(3) mol(-1) l and 1.51, respectively. This method provided a fast, sensible and simple technique for the study of drug-protein interactions.
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Affiliation(s)
- Xu-Ni Cao
- Department of Chemistry, East China, Normal University, Shanghai 200062, China
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