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Hoxie N, Qiu Y, Kales SC, Schneider R, Hu X, Dalal A, Ford-Scheimer SL, Wiseman R, Tsukamoto T, Wei H, Slusher BS, Janiszewski JS, Hall MD. Development of a high-throughput dual-stream liquid chromatography-tandem mass spectrometry method to screen for inhibitors of glutamate carboxypeptidase II. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2024:e9772. [PMID: 38867136 DOI: 10.1002/rcm.9772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/25/2024] [Accepted: 05/01/2024] [Indexed: 06/14/2024]
Abstract
RATIONALE Glutamate carboxypeptidase II (GCPII) catalyzes the hydrolysis of N-acetylaspartylglutamate (NAAG) to yield glutamate (Glu) and N-acetylaspartate (NAA). Inhibition of GCPII has been shown to remediate the neurotoxicity of excess Glu in a variety of cell and animal disease models. A robust high-throughput liquid chromatography-tandem mass spectrometry (LC/MS/MS) method was needed to quantify GCPII enzymatic activity in a biochemical high-throughput screening assay. METHODS A dual-stream LC/MS/MS method was developed. Two parallel eluent streams ran identical HILIC gradient methods on BEH-Amide (2 × 30 mm) columns. Each LC channel was run independently, and the cycle time was 2 min per channel. Overall throughput was 1 min per sample for the dual-channel integrated system. Multiply injected acquisition files were split during data review, and batch metadata were automatically paired with raw data during the review process. RESULTS Two LC sorbents, BEH-Amide and Penta-HILIC, were tested to separate the NAAG cleavage product Glu from isobaric interference and ion suppressants in the bioassay matrix. Early elution of NAAG and NAA on BEH-Amide allowed interfering species to be diverted to waste. The limit of quantification was 0.1 pmol for Glu. The Z-factor of this assay averaged 0.85. Over 36 000 compounds were screened using this method. CONCLUSIONS A fast gradient dual-stream LC/MS/MS method for Glu quantification in GCPII biochemical screening assay samples was developed and validated. HILIC separation chemistry offers robust performance and unique selectivity for targeted positive mode quantification of Glu, NAA, and NAAG.
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Affiliation(s)
- Nate Hoxie
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Yixuan Qiu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Stephen C Kales
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Rick Schneider
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Xin Hu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Anu Dalal
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Stephanie L Ford-Scheimer
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Robyn Wiseman
- Johns Hopkins Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Johns Hopkins Drug Discovery and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Takashi Tsukamoto
- Johns Hopkins Drug Discovery and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Huijun Wei
- Johns Hopkins Drug Discovery and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Barbara S Slusher
- Johns Hopkins Drug Discovery and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - John S Janiszewski
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Matthew D Hall
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
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Zhou W, Lv X, Zhang S, Gao Z, Li B, Wang X. A new approach towards highly sensitive detection of endogenous N-acetylaspartic acid, N-acetylglutamic acid, and N-acetylaspartylglutamic acid in brain tissues based on strong anion exchange monolith microextraction coupled with UHPLC-MS/MS. Mikrochim Acta 2024; 191:360. [PMID: 38819644 DOI: 10.1007/s00604-024-06431-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 05/12/2024] [Indexed: 06/01/2024]
Abstract
A novel in-tube solid-phase microextraction coupled with an ultra-high performance liquid chromatography-mass spectrometry method has been established for simultaneous quantification of three crucial brain biomarkers N-acetylaspartic acid (NAA), N-acetylglutamic acid (NAG), and N-acetylaspartylglutamic acid (NAAG). A polymer monolith with quaternary ammonium as the functional group was designed and exhibited efficient enrichment of target analytes through strong anion exchange interaction. Under the optimized conditions, the proposed method displayed wide linear ranges (0.1-80 nM for NAA and NAG, 0.2-160 nM for NAAG) with good precision (RSDs were lower than 15%) and low limits of detection (0.019-0.052 nM), which is by far the most sensitive approach for NAA, NAG, and NAAG determination. Furthermore, this approach has been applied to measure the target analytes in mouse brain samples, and endogenous NAA, NAG, and NAAG were successfully detected and quantified from only around 5 mg of cerebral cortex, cerebellum, and hippocampus. Compared with existing methods, the newly developed method in the current study provides highest sensitivity and lowest sample consumption for NAA, NAG, and NAAG measurements, which would potentially be utilized in determining and tracking these meaningful brain biomarkers in diseases or treatment processes, benefiting the investigations of pathophysiology and treatment of brain disorders.
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Affiliation(s)
- Wenxiu Zhou
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell & Therapeutic Antibody, National Key Laboratory of Innovative Immunotherapy, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Xiaoyuan Lv
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell & Therapeutic Antibody, National Key Laboratory of Innovative Immunotherapy, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Shengman Zhang
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell & Therapeutic Antibody, National Key Laboratory of Innovative Immunotherapy, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Zhenye Gao
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell & Therapeutic Antibody, National Key Laboratory of Innovative Immunotherapy, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Bingjie Li
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell & Therapeutic Antibody, National Key Laboratory of Innovative Immunotherapy, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Xin Wang
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell & Therapeutic Antibody, National Key Laboratory of Innovative Immunotherapy, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China.
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Grønbæk-Thygesen M, Hartmann-Petersen R. Cellular and molecular mechanisms of aspartoacylase and its role in Canavan disease. Cell Biosci 2024; 14:45. [PMID: 38582917 PMCID: PMC10998430 DOI: 10.1186/s13578-024-01224-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 03/24/2024] [Indexed: 04/08/2024] Open
Abstract
Canavan disease is an autosomal recessive and lethal neurological disorder, characterized by the spongy degeneration of the white matter in the brain. The disease is caused by a deficiency of the cytosolic aspartoacylase (ASPA) enzyme, which catalyzes the hydrolysis of N-acetyl-aspartate (NAA), an abundant brain metabolite, into aspartate and acetate. On the physiological level, the mechanism of pathogenicity remains somewhat obscure, with multiple, not mutually exclusive, suggested hypotheses. At the molecular level, recent studies have shown that most disease linked ASPA gene variants lead to a structural destabilization and subsequent proteasomal degradation of the ASPA protein variants, and accordingly Canavan disease should in general be considered a protein misfolding disorder. Here, we comprehensively summarize the molecular and cell biology of ASPA, with a particular focus on disease-linked gene variants and the pathophysiology of Canavan disease. We highlight the importance of high-throughput technologies and computational prediction tools for making genotype-phenotype predictions as we await the results of ongoing trials with gene therapy for Canavan disease.
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Affiliation(s)
- Martin Grønbæk-Thygesen
- The Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, 2200N, Copenhagen, Denmark.
| | - Rasmus Hartmann-Petersen
- The Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, 2200N, Copenhagen, Denmark.
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Yu H, Yu J, Li L, Zhang Y, Xin S, Ni X, Sun Y, Song K. Recent Progress of the Practical Applications of the Platinum Nanoparticle-Based Electrochemistry Biosensors. Front Chem 2021; 9:677876. [PMID: 34012952 PMCID: PMC8128108 DOI: 10.3389/fchem.2021.677876] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 04/07/2021] [Indexed: 11/28/2022] Open
Abstract
The detection of biomolecules using various biosensors with excellent sensitivity, selectivity, stability, and reproducibility, is of great significance in the analytical and biomedical fields toward achieving their practical applications. Noble metal nanoparticles are favorable candidates due to their unique optical, surface electrical effect, and catalytic properties. Among these noble metal nanoparticles, platinum nanoparticles (Pt NPs) have been widely employed for the detection of bioactive substances such as glucose, glutamic acid, and hormones. However, there is still a long way to go before the potential challenges in the practical applications of biomolecules are fully overcome. Bearing this in mind, combined with our research experience, we summarized the recent progress of the Pt NP-based biosensors and highlighted the current problems that exist in their practical applications. The current review would provide fundamental guidance for future applications using the Pt NP-based biosensors in food, agricultural, and medical fields.
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Affiliation(s)
- Han Yu
- School of Life Sciences, Changchun Normal University, Changchun, China
| | - Jingbo Yu
- School of Life Sciences, Changchun Normal University, Changchun, China
| | - Linlin Li
- School of Life Sciences, Changchun Normal University, Changchun, China
| | - Yujia Zhang
- School of Life Sciences, Changchun Normal University, Changchun, China
| | - Shuquan Xin
- School of Life Sciences, Changchun Normal University, Changchun, China
| | - Xiuzhen Ni
- School of Life Sciences, Changchun Normal University, Changchun, China
| | - Yuan Sun
- Center of Pharmaceutical Engineering and Technology, Harbin University of Commerce, Harbin, China
| | - Kai Song
- School of Life Sciences, Changchun Normal University, Changchun, China
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A Highly Sensitive Amperometric Glutamate Oxidase Microbiosensor Based on a Reduced Graphene Oxide/Prussian Blue Nanocube/Gold Nanoparticle Composite Film-Modified Pt Electrode. SENSORS 2020; 20:s20102924. [PMID: 32455706 PMCID: PMC7284453 DOI: 10.3390/s20102924] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 01/17/2023]
Abstract
A simple method that relies only on an electrochemical workstation has been investigated to fabricate a highly sensitive glutamate microbiosensor for potential neuroscience applications. In this study, in order to develop the highly sensitive glutamate electrode, a 100 µm platinum wire was modified by the electrochemical deposition of gold nanoparticles, Prussian blue nanocubes, and reduced graphene oxide sheets, which increased the electroactive surface area; and the chitosan layer, which provided a suitable environment to bond the glutamate oxidase. The optimization of the fabrication procedure and analytical conditions is described. The modified electrode was characterized using field emission scanning electron microscopy, impedance spectroscopy, and cyclic voltammetry. The results exhibited its excellent sensitivity for glutamate detection (LOD = 41.33 nM), adequate linearity (50 nM-40 µM), ascendant reproducibility (RSD = 4.44%), and prolonged stability (more than 30 repetitive potential sweeps, two-week lifespan). Because of the important role of glutamate in neurotransmission and brain function, this small-dimension, high-sensitivity glutamate electrode is a promising tool in neuroscience research.
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A multi-matrix HILIC-MS/MS method for the quantitation of endogenous small molecule neurological biomarker N- acetyl aspartic acid (NAA). J Pharm Biomed Anal 2017; 140:11-19. [DOI: 10.1016/j.jpba.2017.03.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/10/2017] [Accepted: 03/11/2017] [Indexed: 11/21/2022]
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7
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Jurdáková H, Górová R, Addová G, Behúlová D, Ostrovský I. The state of treatment approach and diagnostics in Canavan disease with focus on the determination of N-acetylasparic acid. CHEMICAL PAPERS 2017. [DOI: 10.1007/s11696-016-0033-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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8
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Baslow MH, Cain CK, Sears R, Wilson DA, Bachman A, Gerum S, Guilfoyle DN. Stimulation-induced transient changes in neuronal activity, blood flow and N-acetylaspartate content in rat prefrontal cortex: a chemogenetic fMRS-BOLD study. NMR IN BIOMEDICINE 2016; 29:1678-1687. [PMID: 27696530 PMCID: PMC5123928 DOI: 10.1002/nbm.3629] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 08/11/2016] [Accepted: 08/29/2016] [Indexed: 06/01/2023]
Abstract
Brain activation studies in humans have shown the dynamic nature of neuronal N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) based on changes in their MRS signals in response to stimulation. These studies demonstrated that upon visual stimulation there was a focal increase in cerebral blood flow (CBF) and a decrease in NAA or in the total of NAA and NAAG signals in the visual cortex, and that these changes were reversed upon cessation of stimulation. In the present study we have developed an animal model in order to explore the relationships between brain stimulation, neuronal activity, CBF and NAA. We use "designer receptor exclusively activated by designer drugs" (DREADDs) technology for site-specific neural activation, a local field potential electrophysiological method for measurement of changes in the rate of neuronal activity, functional MRS for measurement of changes in NAA and a blood oxygenation level-dependent (BOLD) MR technique for evaluating changes in CBF. We show that stimulation of the rat prefrontal cortex using DREADDs results in the following: (i) an increase in level of neuronal activity; (ii) an increase in BOLD and (iii) a decrease in the NAA signal. These findings show for the first time the tightly coupled relationships between stimulation, neuron activity, CBF and NAA dynamics in brain, and also provide the first demonstration of the novel inverse stimulation-NAA phenomenon in an animal model.
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Affiliation(s)
- Morris H. Baslow
- Center for Biomedical Imaging and Neuromodulation, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, 10962, USA
| | - Christopher K. Cain
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, 10962, USA
- Department of Child & Adolescent Psychiatry, New York University Langone School of Medicine, 560 1 Avenue, New York, NY, 10016, USA
| | - Robert Sears
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, 10962, USA
- Department of Child & Adolescent Psychiatry, New York University Langone School of Medicine, 560 1 Avenue, New York, NY, 10016, USA
- Department of Neuroscience & Physiology, New York University Langone School of Medicine, 560 1 Avenue, New York, NY, 10016, USA
| | - Donald A. Wilson
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, 10962, USA
- Department of Child & Adolescent Psychiatry, New York University Langone School of Medicine, 560 1 Avenue, New York, NY, 10016, USA
- Department of Neuroscience & Physiology, New York University Langone School of Medicine, 560 1 Avenue, New York, NY, 10016, USA
| | - Alvin Bachman
- Center for Biomedical Imaging and Neuromodulation, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, 10962, USA
| | - Scott Gerum
- Center for Biomedical Imaging and Neuromodulation, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, 10962, USA
| | - David N. Guilfoyle
- Center for Biomedical Imaging and Neuromodulation, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, 10962, USA
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l-Glutamate biosensor based on l-glutamate oxidase immobilized onto ZnO nanorods/polypyrrole modified pencil graphite electrode. Biochem Eng J 2016. [DOI: 10.1016/j.bej.2015.10.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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10
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Kinoshita K, Arai K, Kawaura K, Hiyoshi T, Yamaguchi JI. Development, validation, and application of a surrogate analyte method for determining N-acetyl-l-aspartyl-l-glutamic acid levels in rat brain, plasma, and cerebrospinal fluid. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 1003:1-11. [DOI: 10.1016/j.jchromb.2015.09.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 09/04/2015] [Accepted: 09/05/2015] [Indexed: 01/10/2023]
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11
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Song J, Liang B, Han D, Tang X, Lang Q, Feng R, Han L, Liu A. Bacterial cell-surface displaying of thermo-tolerant glutamate dehydrogenase and its application in L-glutamate assay. Enzyme Microb Technol 2014; 70:72-8. [PMID: 25659635 DOI: 10.1016/j.enzmictec.2014.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Revised: 12/01/2014] [Accepted: 12/02/2014] [Indexed: 12/17/2022]
Abstract
In this paper, glutamate dehydrogenase (Gldh) is reported to efficiently display on Escherichia coli cell surface by using N-terminal region of ice the nucleation protein as an anchoring motif. The presence of Gldh was confirmed by SDS-PAGE and enzyme activity assay. Gldh was detected mainly in the outer membrane fraction, suggesting that the Gldh was displayed on the bacterial cell surface. The optimal temperature and pH for the bacteria cell-surface displayed Gldh (bacteria-Gldh) were 70°C and 9.0, respectively. Additionally, the fusion protein retained almost 100% of its initial enzymatic activity after 1 month incubation at 4°C. Transition metal ions could inhibit the enzyme activity to different extents, while common anions had little adverse effect on enzyme activity. Importantly, the displayed Gldh is most specific to l-glutamate reported so far. The bacterial Gldh was enabled to catalyze oxidization of l-glutamate with NADP(+) as cofactor, and the resultant NADPH can be detected spectrometrically at 340nm. The bacterial-Gldh based l-glutamate assay was established, where the absorbance at 340nm increased linearly with the increasing l-glutamate concentration within the range of 10-400μM. Further, the proposed approach was successfully applied to measure l-glutamate in real samples.
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Affiliation(s)
- Jianxia Song
- Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, 238 Songling Road, Qingdao 266100, China; Laboratory for Biosensing, and Key Laboratory of Biofuels, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
| | - Bo Liang
- Laboratory for Biosensing, and Key Laboratory of Biofuels, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
| | - Dongfei Han
- Laboratory for Biosensing, and Key Laboratory of Biofuels, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
| | - Xiangjiang Tang
- Laboratory for Biosensing, and Key Laboratory of Biofuels, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
| | - Qiaolin Lang
- Laboratory for Biosensing, and Key Laboratory of Biofuels, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China
| | - Ruirui Feng
- Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, 238 Songling Road, Qingdao 266100, China
| | - Lihui Han
- Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education, and College of Chemistry and Chemical Engineering, Ocean University of China, 238 Songling Road, Qingdao 266100, China.
| | - Aihua Liu
- Laboratory for Biosensing, and Key Laboratory of Biofuels, Qingdao Institute of Bioenergy & Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, China.
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Batra B, Kumari S, Pundir CS. Construction of glutamate biosensor based on covalent immobilization of glutamate oxidase on polypyrrole nanoparticles/polyaniline modified gold electrode. Enzyme Microb Technol 2014; 57:69-77. [PMID: 24629270 DOI: 10.1016/j.enzmictec.2014.02.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 01/23/2014] [Accepted: 02/01/2014] [Indexed: 11/25/2022]
Abstract
A method is described for construction of a highly sensitive electrochemical biosensor for detection of glutamate. The biosensor is based on covalent immobilization of glutamate oxidase (GluOx) onto polypyrrole nanoparticles and polyaniline composite film (PPyNPs/PANI) electrodeposited onto Au electrode. The enzyme electrode was characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infra-red spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). The biosensor showed optimum response within 3s at pH 7.5 (0.1 M sodium phosphate) and 35 °C, when operated at 50 mV s⁻¹. It exhibited excellent sensitivity (detection limit as 0.1 nM), fast response time and wider linear range (from 0.02 to 400 μM). Analytical recovery of added glutamate (5 mM and 10 mM) was 95.56 and 97%, while within batch and between batch coefficients of variation were 3.2% and 3.35% respectively. The enzyme electrode was used 100 times over a period of 60 days, when stored at 4 °C. The biosensor measured glutamate level in food stuff, which correlated well with a standard colorimetric method (r=0.99).
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Affiliation(s)
- Bhawna Batra
- Department of Biochemistry, M D University, Rohtak 124001, India
| | - Seema Kumari
- Department of Biochemistry, M D University, Rohtak 124001, India
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Wang ZH, Xia JF, Han Q, Shi HN, Guo XM, Wang H, Ding MY. Multi-walled carbon nanotube as a solid phase extraction adsorbent for analysis of indole-3-butyric acid and 1-naphthylacetic acid in plant samples. CHINESE CHEM LETT 2013. [DOI: 10.1016/j.cclet.2013.04.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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14
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Batra B, Pundir CS. An amperometric glutamate biosensor based on immobilization of glutamate oxidase onto carboxylated multiwalled carbon nanotubes/gold nanoparticles/chitosan composite film modified Au electrode. Biosens Bioelectron 2013; 47:496-501. [PMID: 23628843 DOI: 10.1016/j.bios.2013.03.063] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 03/24/2013] [Indexed: 11/29/2022]
Abstract
A method is described for the construction of a novel amperometric glutamate biosensor based on covalent immobilization of glutamate oxidase (GluOx) onto, carboxylated multi walled carbon nanotubes (cMWCNT), gold nanoparticles (AuNPs) and chitosan (CHIT) composite film electrodeposited on the surface of a Au electrode. The GluOx/cMWCNT/AuNP/CHIT modified Au electrode was characterized by scanning electron microscopy (SEM), fourier transform infra-red (FTIR) spectroscopy, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The biosensor measured current due to electrons generated at 0.135V against Ag/AgCl from H2O2, which is produced from glutamate by immobilized GluOx. The biosensor showed optimum response within 2s at pH 7.5 and 35°C. A linear relationship was obtained between a wide glutamate concentration range (5-500μM) and current (μA) under optimum conditions. The biosensor showed high sensitivity (155nA/μM/cm(2)), low detection limit (1.6μM) and good storage stability. The biosensor was unaffected by a number of serum substances at their physiological concentrations. The biosensor was evaluated and employed for determination of glutamate in sera from apparently healthy subjects and persons suffering from epilepsy.
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Affiliation(s)
- Bhawna Batra
- Department of Biochemistry, M.D. University, Rohtak 124001, India
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Baslow MH, Guilfoyle DN. Are Astrocytes the Missing Link Between Lack of Brain Aspartoacylase Activity and the Spongiform Leukodystrophy in Canavan Disease? Neurochem Res 2009; 34:1523-34. [DOI: 10.1007/s11064-009-9958-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Accepted: 03/09/2009] [Indexed: 10/21/2022]
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16
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A novel key–lock mechanism for inactivating amino acid neurotransmitters during transit across extracellular space. Amino Acids 2009; 38:51-5. [DOI: 10.1007/s00726-009-0232-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Accepted: 01/05/2009] [Indexed: 10/21/2022]
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