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Fejfarová V, Jarošíková R, Antalová S, Husáková J, Wosková V, Beca P, Mrázek J, Tůma P, Polák J, Dubský M, Sojáková D, Lánská V, Petrlík M. Does PAD and microcirculation status impact the tissue availability of intravenously administered antibiotics in patients with infected diabetic foot? Results of the DFIATIM substudy. Front Endocrinol (Lausanne) 2024; 15:1326179. [PMID: 38774229 PMCID: PMC11106387 DOI: 10.3389/fendo.2024.1326179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 04/16/2024] [Indexed: 05/24/2024] Open
Abstract
Aims/hypothesis The aim of this substudy (Eudra CT No:2019-001997-27)was to assess ATB availability in patients with infected diabetic foot ulcers(IDFUs)in the context of microcirculation and macrocirculation status. Methods For this substudy, we enrolled 23 patients with IDFU. Patients were treated with boluses of amoxicillin/clavulanic acid(AMC)(12patients) or ceftazidime(CTZ)(11patients). After induction of a steady ATB state, microdialysis was performed near the IDFU. Tissue fluid samples from the foot and blood samples from peripheral blood were taken within 6 hours. ATB potential efficacy was assessed by evaluating the maximum serum and tissue ATB concentrations(Cmax and Cmax-tissue)and the percentage of time the unbound drug tissue concentration exceeds the minimum inhibitory concentration (MIC)(≥100% tissue and ≥50%/60% tissue fT>MIC). Vascular status was assessed by triplex ultrasound, ankle-brachial and toe-brachial index tests, occlusive plethysmography comprising two arterial flow phases, and transcutaneous oxygen pressure(TcPO2). Results Following bolus administration, the Cmax of AMC was 91.8 ± 52.5 μgmL-1 and the Cmax-tissue of AMC was 7.25 ± 4.5 μgmL-1(P<0.001). The Cmax for CTZ was 186.8 ± 44.1 μgmL-1 and the Cmax-tissue of CTZ was 18.6 ± 7.4 μgmL-1(P<0.0001). Additionally, 67% of patients treated with AMC and 55% of those treated with CTZ achieved tissue fT>MIC levels exceeding 50% and 60%, respectively. We observed positive correlations between both Cmax-tissue and AUCtissue and arterial flow. Specifically, the correlation coefficient for the first phase was r=0.42; (P=0.045), and for the second phase, it was r=0.55(P=0.01)and r=0.5(P=0.021). Conclusions Bactericidal activity proved satisfactory in only half to two-thirds of patients with IDFUs, an outcome that appears to correlate primarily with arterial flow.
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Affiliation(s)
- Vladimíra Fejfarová
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
- Department of Internal Medicine, Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Radka Jarošíková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
- Department of Internal Medicine, Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Simona Antalová
- Department of Clinical Pharmacy and Drug Information Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Jitka Husáková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Veronika Wosková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Pavol Beca
- Department of Clinical Pharmacy and Drug Information Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Jakub Mrázek
- Laboratory of Anaerobic Microbiology, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Prague, Czechia
| | - Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague, Czechia
| | - Jan Polák
- Department of Pathophysiology, Third Faculty of Medicine, Charles University, Prague, Czechia
| | - Michal Dubský
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Dominika Sojáková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Věra Lánská
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Martin Petrlík
- Vascular and Internal Medicine Outpatient Clinic, Prague, Czechia
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Xu X, Zuo Y, Chen S, Hatami A, Gu H. Advancements in Brain Research: The In Vivo/In Vitro Electrochemical Detection of Neurochemicals. BIOSENSORS 2024; 14:125. [PMID: 38534232 DOI: 10.3390/bios14030125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/12/2024] [Accepted: 02/20/2024] [Indexed: 03/28/2024]
Abstract
Neurochemicals, crucial for nervous system function, influence vital bodily processes and their fluctuations are linked to neurodegenerative diseases and mental health conditions. Monitoring these compounds is pivotal, yet the intricate nature of the central nervous system poses challenges. Researchers have devised methods, notably electrochemical sensing with micro-nanoscale electrodes, offering high-resolution monitoring despite low concentrations and rapid changes. Implantable sensors enable precise detection in brain tissues with minimal damage, while microdialysis-coupled platforms allow in vivo sampling and subsequent in vitro analysis, addressing the selectivity issues seen in other methods. While lacking temporal resolution, techniques like HPLC and CE complement electrochemical sensing's selectivity, particularly for structurally similar neurochemicals. This review covers essential neurochemicals and explores miniaturized electrochemical sensors for brain analysis, emphasizing microdialysis integration. It discusses the pros and cons of these techniques, forecasting electrochemical sensing's future in neuroscience research. Overall, this comprehensive review outlines the evolution, strengths, and potential applications of electrochemical sensing in the study of neurochemicals, offering insights into future advancements in the field.
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Affiliation(s)
- Xiaoxuan Xu
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Yimei Zuo
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Shu Chen
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Amir Hatami
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Prof. Sobouti Boulevard, P.O. Box 45195-1159, Zanjan 45137-66731, Iran
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Hui Gu
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30 Gothenburg, Sweden
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Tůma P. Steady state microdialysis of microliter volumes of body fluids for monitoring of amino acids by capillary electrophoresis with contactless conductivity detection. Anal Chim Acta 2024; 1287:342113. [PMID: 38182349 DOI: 10.1016/j.aca.2023.342113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 12/03/2023] [Accepted: 12/04/2023] [Indexed: 01/07/2024]
Abstract
BACKGROUND The availability of dialysis membranes in the form of hollow fibres with diameters compatible with the fused silica capillaries used in capillary electrophoresis is very limited. However, haemodialysis bicarbonate cartridges commonly used in human medicine containing polysulfone hollow fibres are available on the market and are used for the fabrication of coaxial microdialysis probes. The miniature probe design ensures that steady-state conditions are achieved during microdialysis of minimal volumes of body fluids. RESULTS A coaxial microdialysis probe with a length of 5 cm and an inner diameter of 200 μm is used for microdialysis of 10 μL of body fluid collected into a sampling fused silica capillary with an inner diameter 430 μm. Microdialysis is performed into 0.01 M HCl as a perfusate at stopped flow and 2 μL of the resulting microdialysate are subjected to analysis by capillary electrophoresis with contactless conductivity detection. Microdialysis pre-treatment is verified by analysis of 11 common amino acids at a 100 μM concentration level, resulting in recoveries of 98.3-102.5%. The electrophoretic separation of amino acids is performed in 8.5 M acetic acid at pH 1.37 as a background electrolyte with analysis time up to 4.5 min and LOD in the range of 0.12-0.28 μM. The reproducibility of the developed technique determined for the peak area ranges from 1.2 to 4.5%. Applicability is tested in the quantification of valine and leucine in plasma during fasting and subsequent reconvalescence. SIGNIFICANCE The fabrication of a coaxial microdialysis probe for the laboratory preparation of microliter volumes of various types of clinical samples is described, which is coupled off-line with capillary electrophoretic monitoring of amino acids in 2 μL volumes of microdialysate. The developed methodology is suitable for quantification of 20 amino acids in whole human blood, plasma, tears and has potential for analysis of dry blood spots captured on hollow fibre.
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Affiliation(s)
- Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Ruská 87, 100 00, Prague, 10, Czechia.
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Fukushima T, Kansaku A, Umino M, Sakamoto T, Onozato M. Evaluation of D-amino acid oxidase activity in rat kidney using a D-kynurenine derivative, 6-methylthio-D-kynurenine: An in vivo microdialysis study. Drug Discov Ther 2024; 17:434-439. [PMID: 38044118 DOI: 10.5582/ddt.2023.01083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
D-Amino acid oxidase (DAO), a D-amino acid metabolizing enzyme, is reportedly associated with the psychiatric disease schizophrenia, suggesting a role for DAO inhibitors in its treatment. We have previously reported that DAO catalyzes the conversion of nonfluorescent 6-methylthio-D-kynurenine (MeS-D-KYN) to fluorescent 5-methylthiokynurenic acid (MeS-KYNA) in vitro. The present study aimed to determine the potential of MeS-D-KYN in evaluating DAO activity in vivo using renal microdialysis technique in rats. Male Sprague-Dawley rats were subjected to linear microdialysis probe implantation in the left kidney. Continuous perfusion of MeS-D-KYN was maintained, and DAO activity in the kidney cortex was evaluated by measuring the MeS-KYNA content in the microdialysate. The microdialysate was collected every 30 min and analyzed by high-performance liquid chromatography with fluorescence detection, monitored at 450 nm with an excitation wavelength of 364 nm. A significant production of MeS-KYNA was observed during, but not before, infusion of MeS-D-KYN, indicating that this compound is not endogenous. MeS-KYNA production was suppressed by the co-infusion of DAO inhibitor, 5-chlorobenzo[d]isoxazol-3-ol (CBIO), suggesting that MeS-D-KYN was converted to MeS-KYNA by renal DAO. Moreover, oral administration of CBIO effectively suppressed DAO activity in a dose-dependent manner. DAO converted MeS-D-KYN to MeS-KYNA in vivo, suggesting the potential of this compound in evaluating DAO activity. The use of the renal microdialysis technique developed in this study facilitates the monitoring of DAO activity in live experimental animals.
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Affiliation(s)
- Takeshi Fukushima
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Ayano Kansaku
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Maho Umino
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Tatsuya Sakamoto
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Mayu Onozato
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
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Nestor L, De Bundel D, Vander Heyden Y, Smolders I, Van Eeckhaut A. Unravelling the brain metabolome: A review of liquid chromatography - mass spectrometry strategies for extracellular brain metabolomics. J Chromatogr A 2023; 1712:464479. [PMID: 37952387 DOI: 10.1016/j.chroma.2023.464479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/27/2023] [Accepted: 10/29/2023] [Indexed: 11/14/2023]
Abstract
The analysis of the brain extracellular metabolome is of interest for numerous subdomains within neuroscience. Not only does it provide information about normal physiological functions, it is even more of interest for biomarker discovery and target discovery in disease. The extracellular analysis of the brain is particularly interesting as it provides information about the release of mediators in the brain extracellular fluid to look at cellular signaling and metabolic pathways through the release, diffusion and re-uptake of neurochemicals. In vivo samples are obtained through microdialysis, cerebral open-flow microperfusion or solid-phase microextraction. The analytes of potential interest are typically low in concentration and can have a wide range of physicochemical properties. Liquid chromatography coupled to mass spectrometry has proven its usefulness in brain metabolomics. It allows sensitive and specific analysis of low sample volumes, obtained through different approaches. Several strategies for the analysis of the extracellular fluid have been proposed. The most widely used approaches apply sample derivatization, specific stationary phases and/or hydrophilic interaction liquid chromatography. Miniaturization of these methods allows an even higher sensitivity. The development of chiral metabolomics is indispensable, as it allows to compare the enantiomeric ratio of compounds and provides even more challenges. Some limitations continue to exist for the previously developed methods and the development of new, more sensitive methods remains needed. This review provides an overview of the methods developed for sampling and liquid chromatography-mass spectrometry analysis of the extracellular metabolome.
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Affiliation(s)
- Liam Nestor
- Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Dimitri De Bundel
- Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Yvan Vander Heyden
- Department of Analytical Chemistry, Applied Chemometrics and Molecular Modelling (FABI), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Ilse Smolders
- Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Ann Van Eeckhaut
- Research group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium.
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Guo L, Mao J, Zhang Q, Fan W, Wang D, Li Z, Huang J, Xie J. Pharmacokinetic and pharmacodynamic studies of nicotine in rat brain: a simultaneous investigation of nicotine metabolites and the release of neurotransmitters in vivo. Front Chem 2023; 11:1275478. [PMID: 37937208 PMCID: PMC10626537 DOI: 10.3389/fchem.2023.1275478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 10/09/2023] [Indexed: 11/09/2023] Open
Abstract
Introduction: The body's ability to metabolize nicotine and the disposition of nicotine in the brain are important determinants of its exposure. Limited knowledge about the near real-time changes of neurochemicals during the brain nicotine metabolic process hinders the recognition of its multiple neuropharmacological effects. Methods: An online microdialysis coupled with UHPLC-HRMS/MS method for the in vivo multi-analysis of nicotine metabolites and several neurotransmitters in rat brain was developed. Whether the systemic modulation of metabolic enzyme CYP2B would modulate nicotine pharmacokinetics and local neurochemical effects was further investigated. Results: The dynamic profiles of over 10 nicotine metabolites and neurotransmitters were simultaneously obtained after a single injection of nicotine (2 mg·kg-1, i.p.) using the new method. Proadifen pretreatment (50 mg·kg-1·d-1, i.p., 4 days) caused significant inhibition of brain CYP2B1 activity. When exposed to nicotine, the brain C max of nicotine was 1.26 times higher and the levels of nicotine metabolites, nornicotine, and nicotine-N-oxide, were decreased by 85.3% and 34.4% in proadifen-pretreated rats. The higher level of brain nicotine induced a greater release of dopamine, serotonin, glutamate, and γ-amino-butyric acid in the nucleus accumbens. The concentrations of nicotine and dopamine were positively correlated, and the average levels of γ-amino-butyric acid and serotonin were 2.7 and 1.2 times higher, respectively, under the inhibition of nicotine metabolism. Discussion: These results demonstrated that inhibiting nicotine metabolism in rats can enhance the residence of brain nicotine and its local neurotransmitter effects. The metabolic activity of nicotine under different physiological conditions could regulate nicotine's bioavailability and its resulting pharmacology.
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Affiliation(s)
- Lulu Guo
- Department of Nutrition and Health, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing, China
- Beijing Life Science Academy, Beijing, China
- Food Laboratory of Zhongyuan, Zhengzhou University, Zhengzhou, China
| | - Jian Mao
- Beijing Life Science Academy, Beijing, China
- Food Laboratory of Zhongyuan, Zhengzhou University, Zhengzhou, China
| | | | - Wu Fan
- Beijing Life Science Academy, Beijing, China
| | | | - Zhonghao Li
- Beijing Life Science Academy, Beijing, China
| | - Jiaqiang Huang
- Department of Nutrition and Health, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing, China
| | - Jianping Xie
- Department of Nutrition and Health, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing, China
- Beijing Life Science Academy, Beijing, China
- Food Laboratory of Zhongyuan, Zhengzhou University, Zhengzhou, China
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Kang S, Jeong Y, Choi JW. Simultaneous Estimation of Tonic Dopamine and Serotonin with High Temporal Resolution In Vitro Using Deep Learning. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2023; 2023:1-4. [PMID: 38083281 DOI: 10.1109/embc40787.2023.10341045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Quantitative measurement of the phasic (changes in several seconds) and tonic (changes in minutes to hours) level changes of neurotransmitters is an essential technique for understanding brain functions and brain diseases regulated by the neurotransmitters. However, monitoring phasic and tonic levels of multiple neurotransmitters is still a challenging technology. Microdialysis can measure the tonic levels of multiple neurotransmitters simultaneously but has a low temporal resolution (minute) to analyze precisely. Fast-scan cyclic voltammetry (FSCV) has high temporal resolution and high sensitivity, but it was not able to simultaneously measure the tonic level of multiple neurotransmitters. The recently proposed deep learning-based FSCV method was still only capable of phasic concentration estimation of neurotransmitters. In this study, we estimate the tonic levels of dopamine and serotonin simultaneously by training a deep-learning network with the extracted tonic information from the FSCV. The proposed deep learning model was validated in vitro to simultaneously estimate tonic concentrations of two neurotransmitters with statistically significantly higher accuracy than previously proposed background subtraction-based models (p<0.001). In particular, in the case of serotonin concentration estimation error, the proposed model showed higher prediction performance than the background subtraction-based model (48 nM and 73 nM, respectively). We expect that the proposed technique will help simultaneous measurement of the phasic and tonic levels of numerous neurotransmitters in vivo soon.Clinical Relevance- This study proposes a method to simultaneously measure tonic dopamine and tonic serotonin with high temporal resolution with a single electrode in the brain.
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Tůma P. Progress in on-line, at-line, and in-line coupling of sample treatment with capillary and microchip electrophoresis over the past 10 years: A review. Anal Chim Acta 2023; 1261:341249. [PMID: 37147053 DOI: 10.1016/j.aca.2023.341249] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 05/07/2023]
Abstract
The review presents an evaluation of the development of on-line, at-line and in-line sample treatment coupled with capillary and microchip electrophoresis over the last 10 years. In the first part, it describes different types of flow-gating interfaces (FGI) such as cross-FGI, coaxial-FGI, sheet-flow-FGI, and air-assisted-FGI and their fabrication using molding into polydimethylsiloxane and commercially available fittings. The second part deals with the coupling of capillary and microchip electrophoresis with microdialysis, solid-phase, liquid-phase, and membrane based extraction techniques. It mainly focuses on modern techniques such as extraction across supported liquid membrane, electroextraction, single drop microextraction, head space microextraction, and microdialysis with high spatial and temporal resolution. Finally, the design of sequential electrophoretic analysers and fabrication of SPE microcartridges with monolithic and molecularly imprinted polymeric sorbents are discussed. Applications include the monitoring of metabolites, neurotransmitters, peptides and proteins in body fluids and tissues to study processes in living organisms, as well as the monitoring of nutrients, minerals and waste compounds in food, natural and wastewater.
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Affiliation(s)
- Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Ruská 87, 100 00, Prague 10, Czech Republic.
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A new electromembrane extraction probe for on-line connection with capillary electrophoresis for determination of substances in biological matrices. Talanta 2023; 254:124149. [PMID: 36463806 DOI: 10.1016/j.talanta.2022.124149] [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: 09/06/2022] [Revised: 11/20/2022] [Accepted: 11/26/2022] [Indexed: 11/30/2022]
Abstract
A miniature probe for electromembrane extraction is developed and constructed. The tubular probe with an internal volume of 1.1 μL is made of polypropylene hollow fiber with a supported liquid membrane of 85% nitrophenyloctyl ether (NPOE) with 15% bis(2-ethylhexyl)phosphonic acid (DEHP). The probe is connected on-line to the electrophoresis with short separation capillary via an air assisted flow gating interface cast from poly (dimethylsiloxane). The compact instrument is computer controlled via LabView. The probe parameters are tested for extraction of creatinine and basic amino acids from artificial solution and human urine. The sensitivity of the electrophoretic determination after 300 s extraction at 150 V compared to the sensitivity without extraction is 4.9-fold and 2.6-fold higher for creatinine and arginine, respectively. The RSDs for peak area measured from 5 repeated extractions of 50 μM solutions are 7.5%, 7.2%, 8.6% and 9.2% for Crea, Lys, Arg and His, respectively. The probe can be used for all-day measurements. The preparation of the probe is simple and requires no special tool.
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Fejfarová V, Jarošíková R, Polák J, Sommerová B, Husáková J, Wosková V, Dubský M, Tůma P. Microdialysis as a tool for antibiotic assessment in patients with diabetic foot: a review. Front Endocrinol (Lausanne) 2023; 14:1141086. [PMID: 37139338 PMCID: PMC10150051 DOI: 10.3389/fendo.2023.1141086] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/17/2023] [Indexed: 05/05/2023] Open
Abstract
Diabetic foot is a serious late complication frequently caused by infection and ischaemia. Both require prompt and aggressive treatment to avoid lower limb amputation. The effectiveness of peripheral arterial disease therapy can be easily verified using triplex ultrasound, ankle-brachial/toe-brachial index examination, or transcutaneous oxygen pressure. However, the success of infection treatment is difficult to establish in patients with diabetic foot. Intravenous systemic antibiotics are recommended for the treatment of infectious complications in patients with moderate or serious stages of infection. Antibiotic therapy should be initiated promptly and aggressively to achieve sufficient serum and peripheral antibiotic concentrations. Antibiotic serum levels are easily evaluated by pharmacokinetic assessment. However, antibiotic concentrations in peripheral tissues, especially in diabetic foot, are not routinely detectable. This review describes microdialysis techniques that have shown promise in determining antibiotic levels in the surroundings of diabetic foot lesions.
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Affiliation(s)
- Vladimíra Fejfarová
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
- Second Faculty of Medicine, Charles University, Prague, Czechia
- *Correspondence: Vladimíra Fejfarová,
| | - Radka Jarošíková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
- Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Jan Polák
- Department of Pathophysiology, Third Faculty of Medicine, Charles University, Prague, Czechia
| | - Blanka Sommerová
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague, Czechia
| | - Jitka Husáková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Veronika Wosková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Michal Dubský
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague, Czechia
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Tůma P. Monitoring of biologically active substances in clinical samples by capillary and microchip electrophoresis with contactless conductivity detection: A review. Anal Chim Acta 2022; 1225:340161. [DOI: 10.1016/j.aca.2022.340161] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 07/08/2022] [Accepted: 07/08/2022] [Indexed: 12/11/2022]
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12
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Tůma P, Jaček M, Sommerová B, Dlouhý P, Jarošíková R, Husáková J, Wosková V, Fejfarová V. Monitoring of amoxicilline and ceftazidime in the microdialysate of diabetic foot and serum by capillary electrophoresis with contactless conductivity detection. Electrophoresis 2022; 43:1129-1139. [PMID: 35072285 DOI: 10.1002/elps.202100366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/17/2021] [Accepted: 12/23/2021] [Indexed: 11/11/2022]
Abstract
Determination of the broad-spectrum antibiotics amoxicilline (AMX) and ceftazidime (CTZ) in blood serum and microdialysates of the subcutaneous tissue of the lower limbs is performed using CE with contactless conductivity detection (C4 D). Baseline separation of AMX is achieved in 0.5 M acetic acid as the background electrolyte and separation of CTZ in 3.2 M acetic acid with addition of 13% v/v methanol. The CE-C4 D determination is performed in a 25 µm capillary with suppression of the EOF using INST-coating on an effective length of 18 cm and the attained migration time is 4.2 min for AMX and 4.4 min for CTZ. The analysis was performed using 20 µl of serum and 15 µl of microdialysate, treated by the addition of acetonitrile in a ratio of 1/3 v/v and the sample is injected into the capillary using the large volume sample stacking technique. The LOQ attained in the microdialysate is 148 ng/ml for AMX and 339 ng/ml for CTZ, and in serum 143 ng/ml for AMX and 318 ng/ml for CTZ. The CE-C4 D method is employed for monitoring the passage of AMX and CTZ from the blood circulatory system into the subcutaneous tissue at the sites of diabetic ulceration in patients suffering from diabetic foot syndrome and also for measuring the pharmacokinetics following intravenous application of bolus antibiotic doses.
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Affiliation(s)
- Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague 10, Czech Republic
| | - Martin Jaček
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague 10, Czech Republic
| | - Blanka Sommerová
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague 10, Czech Republic
| | - Pavel Dlouhý
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague 10, Czech Republic
| | - Radka Jarošíková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague 4, Czech Republic
| | - Jitka Husáková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague 4, Czech Republic
| | - Veronika Wosková
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague 4, Czech Republic
| | - Vladimíra Fejfarová
- Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague 4, Czech Republic
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Tjahjono N, Jin Y, Hsu A, Roukes M, Tian L. Letting the little light of mind shine: Advances and future directions in neurochemical detection. Neurosci Res 2022; 179:65-78. [PMID: 34861294 PMCID: PMC9508992 DOI: 10.1016/j.neures.2021.11.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 12/12/2022]
Abstract
Synaptic transmission via neurochemical release is the fundamental process that integrates and relays encoded information in the brain to regulate physiological function, cognition, and emotion. To unravel the biochemical, biophysical, and computational mechanisms of signal processing, one needs to precisely measure the neurochemical release dynamics with molecular and cell-type specificity and high resolution. Here we reviewed the development of analytical, electrochemical, and fluorescence imaging approaches to detect neurotransmitter and neuromodulator release. We discussed the advantages and practicality in implementation of each technology for ease-of-use, flexibility for multimodal studies, and challenges for future optimization. We hope this review will provide a versatile guide for tool engineering and applications for recording neurochemical release.
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Affiliation(s)
- Nikki Tjahjono
- Biomedical Engineering Graduate Group, University of California, Davis, Davis, CA, 95616, USA
| | - Yihan Jin
- Neuroscience Graduate Group, University of California, Davis, Davis, CA, 95618, USA
| | - Alice Hsu
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Michael Roukes
- Department of Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Lin Tian
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Davis, CA, 95616, USA.
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14
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Lubken RM, de Jong AM, Prins MWJ. Real-Time Monitoring of Biomolecules: Dynamic Response Limits of Affinity-Based Sensors. ACS Sens 2022; 7:286-295. [PMID: 34978190 PMCID: PMC8805115 DOI: 10.1021/acssensors.1c02307] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
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Sensors for monitoring
biomolecular dynamics in biological systems
and biotechnological processes in real time, need to accurately and
precisely reconstruct concentration–time profiles. This requirement
becomes challenging when transport processes and biochemical kinetics
are important, as is typically the case for biomarkers at low concentrations.
Here, we present a comprehensive methodology to study the concentration–time
profiles generated by affinity-based sensors that continuously interact
with a biological system of interest. Simulations are performed for
sensors with diffusion-based sampling (e.g., a sensor
patch on the skin) and advection-based sampling (e.g., a sensor connected to a catheter). The simulations clarify how
transport processes and molecular binding kinetics result in concentration
gradients and time delays in the sensor system. Using these simulations,
measured and true concentration–time profiles of insulin were
compared as a function of sensor design parameters. The results lead
to guidelines on how biomolecular monitoring sensors can be designed
for optimal bioanalytical performance in terms of concentration and
time properties.
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Affiliation(s)
- Rafiq M. Lubken
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven 5612 AZ, the Netherlands
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Eindhoven 5612 AZ, the Netherlands
| | - Arthur M. de Jong
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven 5612 AZ, the Netherlands
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Eindhoven 5612 AZ, the Netherlands
| | - Menno W. J. Prins
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven 5612 AZ, the Netherlands
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven 5612 AZ, the Netherlands
- Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Eindhoven 5612 AZ, the Netherlands
- Helia Biomonitoring, Eindhoven 5612 AZ, the Netherlands
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15
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Zeimaran E, Pourshahrestani S, Fathi A, Razak NABA, Kadri NA, Sheikhi A, Baino F. Advances in bioactive glass-containing injectable hydrogel biomaterials for tissue regeneration. Acta Biomater 2021; 136:1-36. [PMID: 34562661 DOI: 10.1016/j.actbio.2021.09.034] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 02/07/2023]
Abstract
Successful tissue regeneration requires a scaffold with tailorable biodegradability, tissue-like mechanical properties, structural similarity to extracellular matrix (ECM), relevant bioactivity, and cytocompatibility. In recent years, injectable hydrogels have spurred increasing attention in translational medicine as a result of their tunable physicochemical properties in response to the surrounding environment. Furthermore, they have the potential to be implanted via minimally invasive procedures while enabling deep penetration, which is considered a feasible alternative to traditional open surgical procedures. However, polymeric hydrogels may lack sufficient stability and bioactivity in physiological environments. Composite hydrogels containing bioactive glass (BG) particulates, synergistically combining the advantages of their constituents, have emerged as multifunctional biomaterials with tailored mechanical properties and biological functionalities. This review paper highlights the recent advances in injectable composite hydrogel systems based on biodegradable polymers and BGs. The influence of BG particle geometry, composition, and concentration on gel formation, rheological and mechanical behavior as well as hydration and biodegradation of injectable hydrogels have been discussed. The applications of these composite hydrogels in tissue engineering are additionally described, with particular attention to bone and skin. Finally, the prospects and current challenges in the development of desirable injectable bioactive hydrogels for tissue regeneration are discussed to outline a roadmap for future research. STATEMENT OF SIGNIFICANCE: Developing a biomaterial that can be readily available for surgery, implantable via minimally invasive procedures, and be able to effectively stimulate tissue regeneration is one of the grand challenges in modern biomedicine. This review summarizes the state-of-the-art of injectable bioactive glass-polymer composite hydrogels to address several challenges in bone and soft tissue repair. The current limitations and the latest evolutions of these composite biomaterials are critically examined, and the roles of design parameters, such as composition, concentration, and size of the bioactive phase, and polymer-glass interactions on the rheological, mechanical, biological, and overall functional performance of hydrogels are detailed. Existing results and new horizons are discussed to provide a state-of-the-art review that may be useful for both experienced and early-stage researchers in the biomaterials community.
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16
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Twenty years of amino acid determination using capillary electrophoresis: A review. Anal Chim Acta 2021; 1174:338233. [DOI: 10.1016/j.aca.2021.338233] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 12/28/2022]
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17
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Experimental Methods for Investigating Uptake 2 Processes In Vivo. Handb Exp Pharmacol 2021; 266:101-117. [PMID: 34196807 DOI: 10.1007/164_2021_452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Neuromodulators are critical regulators of the brain's signaling processes, and thus they are popular pharmacological targets for psychoactive therapies. It is clear that monoamine uptake mechanisms are complicated and subject to multiple uptake mechanisms. Uptake 1 describes uptake of the monoamine via its designated transporter (SERT for serotonin, NET for norepinephrine, and DAT for dopamine), whereas Uptake 2 details multiple transporter types on neurons and glia taking up different types of modulators, not necessarily specific to the monoamine. While Uptake 1 processes have been well-studied over the past few decades, Uptake 2 mechanisms have remained more difficult to study because of the limitations in methods that have the sensitivity and spatiotemporal resolution to look at the subtleties in uptake profiles. In this chapter we review the different experimental approaches that have yielded important information about Uptake 2 mechanisms in vivo. The techniques (scintillation microspectrophotometry, microdialysis, chronoamperometry, and voltammetry) are described in detail, and pivotal studies associated with each method are highlighted. It is clear from these reviewed works that Uptake 2 processes are critical to consider to advance our understanding of the brain and develop effective neuropsychiatric therapies.
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18
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Lu Z, Xu S, Wang H, He E, Liu J, Dai Y, Xie J, Song Y, Wang Y, Wang Y, Qu L, Cai X. PtNPt/MWCNT-PEDOT:PSS-Modified Microelectrode Arrays for the Synchronous Dopamine and Neural Spike Detection in Rat Models of Sleep Deprivation. ACS APPLIED BIO MATERIALS 2021; 4:4872-4884. [PMID: 35007036 DOI: 10.1021/acsabm.1c00172] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In this study, a biosensor assembly based on microelectrode arrays (MEAs) modified with PtNPt/MWCNT-PEDOT:PSS nanocomposites is presented to synchronously detect the dopamine (DA) and electrophysiological activities in rat brains. Different morphological and electrochemical characterizations were conducted to show the excellent mechanical and electrical properties of the as-prepared probes. The developed biosensors realized the sensitive and selective detection of DA with the existence of significant interferences such as uric acid (UA), ascorbic acid (AA), glutamate (Glu), and 3,4-dihydroxyphenylacetic acid (DOPAC). Calibration curve for the DA response was linear with the concentration from 0.05 μM to 79 μM (R = 0.999), with a sensitivity of 30.561 pA/μM and detection limit as low as 50 nM. Finally, the proposed microelectrode was applied to be implanted into the cortex and caudate putamen (CPU) of rats, which was demonstrated to stably measure the synchronous neurochemical and neurophysiological changes caused by 72 h sleep deprivation. The in vivo measuring results showed that the sleep deprivation increased the DA release and neural spike activity in both cortex and CPU. The local field potential (LFP) power in the delta and theta band was significantly increased as well. These changes in brain may reflect the brain's adaptive reaction toward the side effects induced by sleep deprivation and may partially explain the mechanism of forced wakefulness in the presence of accumulated sleep pressure.
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Affiliation(s)
- Zeying Lu
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Shengwei Xu
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Hao Wang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Enhui He
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Juntao Liu
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Yuchuan Dai
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Jingyu Xie
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Yilin Song
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Yun Wang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Yiding Wang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
| | - Lina Qu
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing 100094, China
| | - Xinxia Cai
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100120, China
- University of Chinese Academy of Sciences, Beijing 100042, China
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19
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Valenta AC, D'Amico CI, Dugan CE, Grinias JP, Kennedy RT. A microfluidic chip for on-line derivatization and application to in vivo neurochemical monitoring. Analyst 2021; 146:825-834. [PMID: 33346258 DOI: 10.1039/d0an01729a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Microfluidic chips can perform a broad range of automated fluid manipulation operations for chemical analysis including on-line reactions. Derivatization reactions carried out on-chip reduce manual sample preparation and improve experimental throughput. In this work we develop a chip for on-line benzoyl chloride derivatization coupled to microdialysis, an in vivo sampling technique. Benzoyl chloride derivatization is useful for the analysis of small molecule neurochemicals in complex biological matrices using HPLC-MS/MS. The addition of one or more benzoyl groups to small, polar compounds containing amines, phenols, thiols, and certain alcohols improves reversed phase chromatographic retention, electrospray ionization efficiency, and analyte stability. The current derivatization protocol requires a three-step manual sample preparation, which ultimately limits the utility of this method for rapid sample collection and large sample sets. A glass microfluidic chip was developed for derivatizing microdialysis fractions on-line as they exit the probe for collection and off-line analysis with HPLC-MS/MS. Calibration curves for 21 neurochemicals prepared using the on-chip method showed linearity (R2 > 0.99), limits of detection (0.1-500 nM), and peak area RSDs (4-14%) comparable to manual derivatization. Method temporal resolution was investigated both in vitro and in vivo showing rapid rise times for all analytes, which was limited by fraction length (3 min) rather than the device. The platform was applied to basal measurements in the striatum of awake rats where 19 of 21 neurochemicals were above the limit of detection. For a typical 2 h study, a minimum of 120 pipetting steps are eliminated per animal. Such a device provides a useful tool for the analysis of small molecules in biological matrices which may extend beyond microdialysis to other sampling techniques.
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Affiliation(s)
- Alec C Valenta
- Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan 48109, USA.
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20
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Weber S, Tombelli S, Giannetti A, Trono C, O'Connell M, Wen M, Descalzo AB, Bittersohl H, Bietenbeck A, Marquet P, Renders L, Orellana G, Baldini F, Luppa PB. Immunosuppressant quantification in intravenous microdialysate - towards novel quasi-continuous therapeutic drug monitoring in transplanted patients. Clin Chem Lab Med 2020; 59:935-945. [PMID: 33554521 DOI: 10.1515/cclm-2020-1542] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/06/2020] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Therapeutic drug monitoring (TDM) plays a crucial role in personalized medicine. It helps clinicians to tailor drug dosage for optimized therapy through understanding the underlying complex pharmacokinetics and pharmacodynamics. Conventional, non-continuous TDM fails to provide real-time information, which is particularly important for the initial phase of immunosuppressant therapy, e.g., with cyclosporine (CsA) and mycophenolic acid (MPA). METHODS We analyzed the time course over 8 h of total and free of immunosuppressive drug (CsA and MPA) concentrations measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in 16 kidney transplant patients. Besides repeated blood sampling, intravenous microdialysis was used for continuous sampling. Free drug concentrations were determined from ultracentrifuged EDTA-plasma (UC) and compared with the drug concentrations in the respective microdialysate (µD). µDs were additionally analyzed for free CsA using a novel immunosensor chip integrated into a fluorescence detection platform. The potential of microdialysis coupled with an optical immunosensor for the TDM of immunosuppressants was assessed. RESULTS Using LC-MS/MS, the free concentrations of CsA (fCsA) and MPA (fMPA) were detectable and the time courses of total and free CsA comparable. fCsA and fMPA and area-under-the-curves (AUCs) in µDs correlated well with those determined in UCs (r≥0.79 and r≥0.88, respectively). Moreover, fCsA in µDs measured with the immunosensor correlated clearly with those determined by LC-MS/MS (r=0.82). CONCLUSIONS The new microdialysis-supported immunosensor allows real-time analysis of immunosuppressants and tailor-made dosing according to the AUC concept. It readily lends itself to future applications as minimally invasive and continuous near-patient TDM.
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Affiliation(s)
- Susanne Weber
- Institute of Clinical Chemistry and Pathobiochemistry, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Sara Tombelli
- Institute of Applied Physics "Nello Carrara", National Research Council, Sesto Fiorentino (FI), Italy
| | - Ambra Giannetti
- Institute of Applied Physics "Nello Carrara", National Research Council, Sesto Fiorentino (FI), Italy
| | - Cosimo Trono
- Institute of Applied Physics "Nello Carrara", National Research Council, Sesto Fiorentino (FI), Italy
| | | | - Ming Wen
- Department of Nephrology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Ana B Descalzo
- Department of Organic Chemistry, Universidad Complutense de Madrid, Madrid, Spain
| | - Heike Bittersohl
- Institute of Clinical Chemistry and Pathobiochemistry, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Andreas Bietenbeck
- Institute of Clinical Chemistry and Pathobiochemistry, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Pierre Marquet
- U1248 IPPRITT, INSERM, University of Limoges, Limoges, CHU Limoges, France
| | - Lutz Renders
- Department of Nephrology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,German Centre for Infection Research (DZIF), Munich, Germany
| | - Guillermo Orellana
- Department of Organic Chemistry, Universidad Complutense de Madrid, Madrid, Spain
| | - Francesco Baldini
- Institute of Applied Physics "Nello Carrara", National Research Council, Sesto Fiorentino (FI), Italy
| | - Peter B Luppa
- Institute of Clinical Chemistry and Pathobiochemistry, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
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21
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Tůma P. Determination of amino acids by capillary and microchip electrophoresis with contactless conductivity detection - Theory, instrumentation and applications. Talanta 2020; 224:121922. [PMID: 33379123 DOI: 10.1016/j.talanta.2020.121922] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/22/2020] [Accepted: 11/23/2020] [Indexed: 01/15/2023]
Abstract
This review article summarises aspects of the determination of amino acids using capillary and chip electrophoresis in combination with contactless conductivity detection from their historical beginnings to the present time. Discussion is included of the theory of conductivity detection in electromigration techniques, the design of contactless conductivity cells for detection in capillaries and on microchips, including the use of computer programs for simulation of the conductivity response and the process of the electrophoretic separation of amino acids. Emphasis is placed on optimisation of the background electrolyte composition, chiral separation, multidimensional separation, stacking techniques and the use of multidetection systems. There is also a description of clinical applications, the determination of amino acids in foodstuffs, waters, soils and composts with emphasis on modern techniques of sample treatment, such as microdialysis, liquid membrane extraction and many other techniques.
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Affiliation(s)
- Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Ruská 87, 100 00, Prague 10, Czech Republic.
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22
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Opekar F, Tůma P. Dialysis of one sample drop on-line connected with electrophoresis in short capillary. Talanta 2020; 219:121252. [DOI: 10.1016/j.talanta.2020.121252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 12/25/2022]
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23
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Nagase K, Kanazawa H. Temperature-responsive chromatography for bioseparations: A review. Anal Chim Acta 2020; 1138:191-212. [DOI: 10.1016/j.aca.2020.07.075] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 07/29/2020] [Accepted: 07/30/2020] [Indexed: 02/07/2023]
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24
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Gunawardhana SM, Bulgakova GA, Barybin AM, Thomas SR, Lunte SM. Progress toward the development of a microchip electrophoresis separation-based sensor with electrochemical detection for on-line in vivo monitoring of catecholamines. Analyst 2020; 145:1768-1776. [PMID: 31915763 PMCID: PMC7127871 DOI: 10.1039/c9an01980d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The development of a separation-based sensor for catecholamines based on microdialysis (MD) coupled to microchip electrophoresis (ME) with electrochemical (EC) detection is described. The device consists of a pyrolyzed photoresist film working electrode and a poly(dimethylsiloxane) microchip with a flow-gated sample injection interface. The chip was partially reversibly sealed to the glass substrate by selectively exposing only the top section of the chip to plasma. This partially reversible chip/electrode integration process not only allows the reuse of the working electrode but also greatly enhanced the reproducibility of electrode alignment with the separation channel. The developed MD-ME-EC system was then tested using l-DOPA, 3-O-MD, HVA, DOPAC, and dopamine standards, which were separated in less than 100 seconds using a background electrolyte consisting of 15 mM sodium phosphate (pH 7.4), 15 mM sodium dodecyl sulfate, and 2.5 mM boric acid. A potential of +1.0 V vs. Ag/AgCl was used for amperometric detection of the analytes. The device was evaluated for on-line monitoring of the conversion of l-DOPA to dopamine in vitro and for monitoring dopamine release in an anesthetized rat in vivo following high K+ stimulation. The system was able to detect stimulated dopamine release in vivo but not endogenous levels of dopamine.
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Affiliation(s)
- Shamal M Gunawardhana
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA. and Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Galina A Bulgakova
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA. and Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Anton M Barybin
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA. and Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Sara R Thomas
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA. and Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Susan M Lunte
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA. and Department of Chemistry, University of Kansas, Lawrence, KS, USA and Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
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25
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Tůma P, Sommerová B, Daněček V. On-line coupling of capillary electrophoresis with microdialysis for determining saccharides in dairy products and honey. Food Chem 2020; 316:126362. [PMID: 32050115 DOI: 10.1016/j.foodchem.2020.126362] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 10/24/2019] [Accepted: 02/04/2020] [Indexed: 12/19/2022]
Abstract
Free sucrose, lactose, galactose, glucose and fructose were determined in yoghurts, milk and honey using on-line coupling of capillary electrophoresis with microdialysis. The dairy products were diluted 50-fold with 10 mmol/L NaOH and sampled using laboratory-made microdialysis probes. The microdialysate was brought to the entrance of the electrophoretic capillary and the coupling consisted in a polydimethylsiloxane (PDMS) cross connector working in the flow-gating interface regime. The electrophoretic analysis was performed in 50 mmol/L NaOH (pH 12.6) background electrolyte, where baseline separation of the five saccharides was achieved in 3.5 min. The LOQs varied in the range 2.3-7.3 mg/L, the number of separation plates varied between 176,000 plates/m for glucose to 326,000 plates/m for galactose and the relative standard deviation (RSD) for ten consecutive analyses of fruit yoghurt was 0.2% for the migration time and 4.4-7.6% for the peak area.
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Affiliation(s)
- Petr Tůma
- Charles University, Third Faculty of Medicine, Department of Hygiene, Ruská 87, 100 00 Prague 10, Czech Republic.
| | - Blanka Sommerová
- Charles University, Third Faculty of Medicine, Department of Hygiene, Ruská 87, 100 00 Prague 10, Czech Republic
| | - Václav Daněček
- Charles University, Third Faculty of Medicine, Department of Biophysics, Ruská 87, 100 00 Prague 10, Czech Republic
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26
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Sung C, Jeon W, Nam KS, Kim Y, Butt H, Park S. Multimaterial and multifunctional neural interfaces: from surface-type and implantable electrodes to fiber-based devices. J Mater Chem B 2020; 8:6624-6666. [DOI: 10.1039/d0tb00872a] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Development of neural interfaces from surface electrodes to fibers with various type, functionality, and materials.
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Affiliation(s)
- Changhoon Sung
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Woojin Jeon
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Kum Seok Nam
- School of Electrical Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Yeji Kim
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Haider Butt
- Department of Mechanical Engineering
- Khalifa University
- Abu Dhabi 127788
- United Arab Emirates
| | - Seongjun Park
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
- KAIST Institute for Health Science and Technology (KIHST)
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27
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Ford R, Devereux SJ, Quinn SJ, O'Neill RD. Carbon nanohorn modified platinum electrodes for improved immobilisation of enzyme in the design of glutamate biosensors. Analyst 2019; 144:5299-5307. [PMID: 31373591 DOI: 10.1039/c9an01085h] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Electrochemical enzymatic biosensors are the subject of research due to their potential for in vivo monitoring of glutamate, which is a key neurotransmitter whose concentration is related to healthy brain function. This study reports the use of biocompatible oxidised carbon nanohorns (o-CNH) with a high surface area, to enhance the immobilization of glutamate oxidase (GluOx) for improved biosensor performance. Two families of biosensors were designed to interact with the anionic GluOx. Family-1 consists of covalently functionalised o-CNH possessing hydrazide (HYZ) and amine (PEG-NH2) terminated surfaces and Family-2 comprised non-covalently functionalised o-CNH with different loadings of polyethyleneimine (PEI) to form a cationic hybrid. Amperometric detection of H2O2 formed by enzymatic oxidation of glutamate revealed a good performance from all designs with the most improved performance by the PEI hybrid systems. The best response was from a o-CNH : PEI ratio of 1 : 10 mg mL-1, which yielded a glutamate calibration plateau, JMAX, of 55 ± 9 μA cm-2 and sensitivity of 111 ± 34 μA mM-1 cm-2. The low KM of 0.31 ± 0.05 mM indicated the retention of the enzyme function, and a limit of detection of 0.02 ± 0.004 μM and a response time of 0.88 ± 0.13 s was determined. The results demonstrate the high sensitivity of these biosensors and their potential for future use for the detection of glutamate in vivo.
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Affiliation(s)
- Rochelle Ford
- School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland.
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Samper IC, Gowers SAN, Booth MA, Wang C, Watts T, Phairatana T, Vallant N, Sandhu B, Papalois V, Boutelle MG. Portable Microfluidic Biosensing System for Real-Time Analysis of Microdialysate in Transplant Kidneys. Anal Chem 2019; 91:14631-14638. [PMID: 31647870 PMCID: PMC7110273 DOI: 10.1021/acs.analchem.9b03774] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Currently, there is a severe shortage of donor kidneys that are fit for transplantation, due in part to a lack of adequate viability assessment tools for transplant organs. This work presents the integration of a novel wireless two-channel amperometric potentiostat with microneedle-based glucose and lactate biosensors housed in a 3D printed chip to create a microfluidic biosensing system that is genuinely portable. The wireless potentiostat transmits data via Bluetooth to an Android app running on a tablet. The whole miniaturized system is fully enclosed and can be integrated with microdialysis to allow continuous monitoring of tissue metabolite levels in real time. We have also developed a wireless portable automated calibration platform so that biosensors can be calibrated away from the laboratory and in transit. As a proof of concept, we have demonstrated the use of this portable analysis system to monitor porcine kidneys for the first time from organ retrieval, through warm ischemia, transportation on ice, right through to cold preservation and reperfusion. The portable system is robust and reliable in the challenging conditions of the abattoir and during kidney transportation and can detect clear physiological changes in the organ associated with clinical interventions.
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Affiliation(s)
- Isabelle C Samper
- Department of Bioengineering , Imperial College London , London SW7 2AZ , U.K
| | - Sally A N Gowers
- Department of Bioengineering , Imperial College London , London SW7 2AZ , U.K
| | - Marsilea A Booth
- Department of Bioengineering , Imperial College London , London SW7 2AZ , U.K
| | - Chu Wang
- Department of Bioengineering , Imperial College London , London SW7 2AZ , U.K
| | - Thomas Watts
- Department of Bioengineering , Imperial College London , London SW7 2AZ , U.K
| | - Tonghathai Phairatana
- Department of Bioengineering , Imperial College London , London SW7 2AZ , U.K.,Institute of Biomedical Engineering, Faculty of Medicine , Prince of Songkla University , Hat Yai 90110 , Thailand
| | - Natalie Vallant
- Department of Surgery and Cancer , Imperial College London , London SW7 2AZ , U.K
| | - Bynvant Sandhu
- Department of Surgery and Cancer , Imperial College London , London SW7 2AZ , U.K
| | - Vassilios Papalois
- Department of Surgery and Cancer , Imperial College London , London SW7 2AZ , U.K
| | - Martyn G Boutelle
- Department of Bioengineering , Imperial College London , London SW7 2AZ , U.K
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Scida K, Plaxco KW, Jamieson BG. High frequency, real-time neurochemical and neuropharmacological measurements in situ in the living body. Transl Res 2019; 213:50-66. [PMID: 31361988 DOI: 10.1016/j.trsl.2019.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/20/2019] [Accepted: 07/11/2019] [Indexed: 12/18/2022]
Abstract
The beautiful and complex brain machinery is perfectly synchronized, and our bodies have evolved to protect it against a myriad of potential threats. Shielded physically by the skull and chemically by the blood brain barrier, the brain processes internal and external information so that we can efficiently relate to the world that surrounds us while simultaneously and unconsciously controlling our vital functions. When coupled with the brittle nature of its internal chemical and electric signals, the brain's "armor" render accessing it a challenging and delicate endeavor that has historically limited our understanding of its structural and neurochemical intricacies. In this review, we briefly summarize the advancements made over the past 10 years to decode the brain's neurochemistry and neuropharmacology in situ, at the site of interest in the brain, with special focus on what we consider game-changing emerging technologies (eg, genetically encoded indicators and electrochemical aptamer-based sensors) and the challenges these must overcome before chronic, in situ chemosensing measurements become routine.
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Affiliation(s)
- Karen Scida
- Diagnostic Biochips, Inc., Glen Burnie, Maryland
| | - Kevin W Plaxco
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California
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30
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Le J, Lin Z, Song L, Wang H, Hong Z. LC-MS/MS combined with in vivo microdialysis sampling from conscious rat striatum for simultaneous determination of active constituents of Yuanhu- Baizhi herb pair and endogenous neurotransmitters: Application to pharmacokinetic and pharmacodynamic study. J Pharm Biomed Anal 2019; 176:112807. [DOI: 10.1016/j.jpba.2019.112807] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 08/04/2019] [Accepted: 08/06/2019] [Indexed: 12/29/2022]
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31
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Öncü Kaya EM, Korkmaz OT, Yeniceli Uğur D, Şener E, Tunçel AN, Tunçel M. Determination of Ochratoxin-A in the brain microdialysates and plasma of awake, freely moving rats using ultra high performance liquid chromatography fluorescence detection method. J Chromatogr B Analyt Technol Biomed Life Sci 2019; 1125:121700. [DOI: 10.1016/j.jchromb.2019.06.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 06/21/2019] [Accepted: 06/22/2019] [Indexed: 12/18/2022]
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Doell A, Schmitz OJ, Hollmann M. Shedding Light into the Subcutis: A Mass Spectrometry Based Immunocapture Assay Enabling Full Characterization of Therapeutic Antibodies after Injection in Vivo. Anal Chem 2019; 91:9490-9499. [DOI: 10.1021/acs.analchem.9b00159] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Annika Doell
- NBE Analytical R&D, AbbVie GmbH & Co. KG, Knollstraße, Ludwigshafen 67061, Germany
| | | | - Markus Hollmann
- NBE Analytical R&D, AbbVie GmbH & Co. KG, Knollstraße, Ludwigshafen 67061, Germany
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Samper IC, Gowers SAN, Rogers ML, Murray DSRK, Jewell SL, Pahl C, Strong AJ, Boutelle MG. 3D printed microfluidic device for online detection of neurochemical changes with high temporal resolution in human brain microdialysate. LAB ON A CHIP 2019; 19:2038-2048. [PMID: 31094398 PMCID: PMC9209945 DOI: 10.1039/c9lc00044e] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This paper presents the design, optimisation and fabrication of a mechanically robust 3D printed microfluidic device for the high time resolution online analysis of biomarkers in a microdialysate stream at microlitre per minute flow rates. The device consists of a microfluidic channel with secure low volume connections that easily integrates electrochemical biosensors for biomarkers such as glutamate, glucose and lactate. The optimisation process of the microfluidic channel fabrication, including for different types of 3D printer, is explained and the resulting improvement in sensor response time is quantified. The time resolution of the device is characterised by recording short lactate concentration pulses. The device is employed to record simultaneous glutamate, glucose and lactate concentration changes simulating the physiological response to spreading depolarisation events in cerebrospinal fluid dialysate. As a proof-of-concept study, the device is then used in the intensive care unit for online monitoring of a brain injury patient, demonstrating its capabilities for clinical monitoring.
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Affiliation(s)
| | | | | | | | - Sharon L Jewell
- Department of Basic and Clinical Neuroscience, King's College, London, UK
| | - Clemens Pahl
- Department of Basic and Clinical Neuroscience, King's College, London, UK
| | - Anthony J Strong
- Department of Basic and Clinical Neuroscience, King's College, London, UK
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Messerli MA, Sarkar A. Advances in Electrochemistry for Monitoring Cellular Chemical Flux. Curr Med Chem 2019; 26:4984-5002. [PMID: 31057100 DOI: 10.2174/0929867326666190506111629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 03/06/2019] [Accepted: 03/12/2019] [Indexed: 11/22/2022]
Abstract
The transport of organic and inorganic molecules, along with inorganic ions across the plasma membrane results in chemical fluxes that reflect the cellular function in healthy and diseased states. Measurement of these chemical fluxes enables the characterization of protein function and transporter stoichiometry, characterization of a single cell and embryo viability prior to implantation, and screening of pharmaceutical agents. Electrochemical sensors emerge as sensitive and non-invasive tools for measuring chemical fluxes immediately outside the cells in the boundary layer, that are capable of monitoring a diverse range of transported analytes including inorganic ions, gases, neurotransmitters, hormones, and pharmaceutical agents. Used on their own or in combination with other methods, these sensors continue to expand our understanding of the function of rare cells and small tissues. Advances in sensor construction and detection strategies continue to improve sensitivity under physiological conditions, diversify analyte detection, and increase throughput. These advances will be discussed in the context of addressing technical challenges to measuring chemical flux in the boundary layer of cells and measuring the resultant changes to the chemical concentration in the bulk media.
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Affiliation(s)
- Mark A Messerli
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD. United States
| | - Anyesha Sarkar
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD. United States
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Tůma P. The Control of Glucose and Lactate Levels in Nutrient Medium After Cell Incubation and in Microdialysates of Human Adipose Tissue by Capillary Electrophoresis with Contactless Conductivity Detection. Methods Mol Biol 2019; 1972:95-108. [PMID: 30847786 DOI: 10.1007/978-1-4939-9213-3_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Two methods of capillary electrophoresis with contactless conductivity detection have been developed for monitoring the levels of glucose and lactate in clinical samples. The separations are performed in uncoated fused silica capillaries with inner diameter 10 or 20 μm, total length 31.5 cm, length to detector 18 cm, using an Agilent electrophoretic instrument with an integrated contactless conductivity detector. Glucose is determined in optimized background electrolyte, 50 mM NaOH with pH 12.6 and 2-deoxyglucose is used as an internal standard; the determination of lactate is performed in 40 mM CHES/NaOH with pH 9.4 and lithium cations as an internal standard. Both substances are determined in minimal volumes of (1) nutrient media after cell incubation, and (2) microdialysates of human adipose tissue; after dilution and filtration as the only treatment of the sample. The migration time of glucose is 2.5 min and that of lactate is 1.5 min with detection limits at the micromolar concentration level. The developed techniques are suitable for sequential monitoring of glucose and lactate over time during metabolic experiments.
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Affiliation(s)
- Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Prague, Czech Republic.
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36
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Zhao XE, He Y, Zhu S, Xu Y, You J, Bai Y, Liu H. Stable isotope labeling derivatization and magnetic dispersive solid phase extraction coupled with UHPLC-MS/MS for the measurement of brain neurotransmitters in post-stroke depression rats administrated with gastrodin. Anal Chim Acta 2019; 1051:73-81. [DOI: 10.1016/j.aca.2018.11.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/23/2018] [Accepted: 11/05/2018] [Indexed: 11/30/2022]
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Tomas A, Stilinović N, Sabo A, Tomić Z. Use of microdialysis for the assessment of fluoroquinolone pharmacokinetics in the clinical practice. Eur J Pharm Sci 2019; 131:230-242. [PMID: 30811969 DOI: 10.1016/j.ejps.2019.02.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 02/22/2019] [Accepted: 02/22/2019] [Indexed: 12/12/2022]
Abstract
Antibacterial drugs, including fluoroquinolones, can exert their therapeutic action only with adequate penetration at the infection site. Multiple factors, such as rate of protein binding, drug liposolubility and organ blood-flow all influence ability of antibiotics to penetrate target tissues. Microdialysis is an in vivo sampling technique that has been successfully applied to measure the distribution of fluoroquinolones in the interstitial fluid of different tissues both in animal studies and clinical setting. Tissue concentrations need to be interpreted within the context of the pathogenesis and causative agents implicated in infections. Integration of microdialysis -derived tissue pharmacokinetics with pharmacodynamic data offers crucial information for correlating exposure with antibacterial effect. This review explores these concepts and provides an overview of tissue concentrations of fluoroquinolones derived from microdialysis studies and explores the therapeutic implications of fluoroquinolone distribution at various target tissues.
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Affiliation(s)
- Ana Tomas
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia.
| | - Nebojša Stilinović
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia
| | - Ana Sabo
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia
| | - Zdenko Tomić
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia
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38
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Xu Y, Zhang Q, Li P, Hong G, Wang D, Liu J, Zhou H, Chai G, Lu B, He S, Zhang W, Sun S, Zhang J, Mao J. Nicotine Pharmacokinetics in Rat Brain and Blood by Simultaneous Microdialysis, Stable-Isotope Labeling, and UHPLC–HRMS: Determination of Nicotine Metabolites. Anal Chem 2019; 91:2916-2922. [DOI: 10.1021/acs.analchem.8b05078] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Yan Xu
- School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Qidong Zhang
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Peng Li
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Guangfeng Hong
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Dingzhong Wang
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Junhui Liu
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Hao Zhou
- Technology Center, China Tobacco Henan Industrial Co., Ltd., Zhengzhou 450000, China
| | - Guobi Chai
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Binbin Lu
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Shengbao He
- China National Tobacco Quality Supervision and Test Center, Zhengzhou 450001, China
| | - Wenjuan Zhang
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Shihao Sun
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Jianxun Zhang
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
| | - Jian Mao
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, China
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39
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Zhuang Z, Shen Z, Chen Y, Dai Z, Zhang X, Mao Y, Zhang B, Zeng H, Chen P, Wu R. Mapping the Changes of Glutamate Using Glutamate Chemical Exchange Saturation Transfer (GluCEST) Technique in a Traumatic Brain Injury Model: A Longitudinal Pilot Study. ACS Chem Neurosci 2019; 10:649-657. [PMID: 30346712 DOI: 10.1021/acschemneuro.8b00482] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Glutamate excitoxicity plays a crucial role in the pathophysiology of traumatic brain injury (TBI) through the initiation of secondary injuries. Glutamate chemical exchange saturation transfer (GluCEST) MRI is a newly developed technique to noninvasively image glutamate in vivo with high sensitivity and spatial resolution. The aim of the present study was to use a rat model of TBI to map changes in brain glutamate distribution and explore the capability of GluCEST imaging for detecting secondary injuries. Sequential GluCEST imaging scans were performed in adult male Sprague-Dawley rats before TBI and at 1, 3, 7, and 14 days after TBI. GluCEST% increased and peaked on day 1 after TBI in the core lesion of injured cortex and peaked on day 3 in the ipsilateral hippocampus, as compared to baseline and controls. GluCEST% gradually declined to baseline by day 14 after TBI. A negative correlation between the GluCEST% of the ipsilateral hippocampus on day 3 and the time in the correct quadrant was observed in injured rats. Immunolabeling for glial fibrillary acidic protein showed significant astrocyte activation in the ipsilateral hippocampus of TBI rats. IL-6 and TNF-α in the core lesion peaked on day 1 postinjury, while those in the ipsilateral hippocampus peaked on day 3. These subsequently gradually declined to sham levels by day 14. It was concluded that GluCEST imaging has potential to be a novel neuroimaging approach for predicting cognitive outcome and to better understand neuroinflammation following TBI.
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Affiliation(s)
- Zerui Zhuang
- Department of Neurosurgery, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Zhiwei Shen
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Yanzi Chen
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Zhuozhi Dai
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Xiaolei Zhang
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Yifei Mao
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Bingna Zhang
- Translational Medicine, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Haiyan Zeng
- Medical College of Shantou University, Shantou 515041, China
| | - Peidong Chen
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
| | - Renhua Wu
- Department of Radiology, The Second Affiliated Hospital, Medical College of Shantou University, Shantou 515041, China
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Gowers SAN, Hamaoui K, Vallant N, Hanna GB, Darzi A, Casanova D, Papalois V, Boutelle MG. An improved rapid sampling microdialysis system for human and porcine organ monitoring in a hospital setting. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2018; 10:5273-5281. [PMID: 31490460 PMCID: PMC6244488 DOI: 10.1039/c8ay01807c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 09/22/2018] [Indexed: 06/10/2023]
Abstract
Online organ monitoring could provide clinicians with critical information regarding organ health prior to transplantation and could aid clinical decision-making. This paper presents the methodology of online microdialysis for real-time monitoring of human organs ex vivo. We describe how rapid sampling microdialysis can be incorporated with organ perfusion machines to create a robust organ monitoring system and demonstrate its use in monitoring human and porcine kidneys as well as human and porcine pancreases. In this paper we also show the potential usefulness of this methodology for evaluating novel interventions in a research setting. The analysis system can be configured either to analyse two analytes in one organ, allowing for ratiometric analysis, or alternatively to monitor one analyte in two organs simultaneously, allowing direct comparison. It was found to be reliable over long monitoring periods in real clinical use. The results clearly show that the analysis system is sensitive to differences between organs and therefore has huge potential as an ex vivo organ monitoring tool.
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Affiliation(s)
| | - Karim Hamaoui
- Department of Surgery & Cancer , Imperial College London , UK
| | - Natalie Vallant
- Department of Surgery & Cancer , Imperial College London , UK
| | - George B Hanna
- Department of Surgery & Cancer , Imperial College London , UK
| | - Ara Darzi
- Department of Surgery & Cancer , Imperial College London , UK
| | - Daniel Casanova
- Department of Surgery , University of Cantabria , Santander , Spain
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Moßhammer M, Schrameyer V, Jensen PØ, Koren K, Kühl M. Extracellular hydrogen peroxide measurements using a flow injection system in combination with microdialysis probes - Potential and challenges. Free Radic Biol Med 2018; 128:111-123. [PMID: 29860128 DOI: 10.1016/j.freeradbiomed.2018.05.089] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 05/14/2018] [Accepted: 05/29/2018] [Indexed: 12/29/2022]
Abstract
There is a strong need for techniques that can quantify the important reactive oxygen species hydrogen peroxide (H2O2) in complex media and in vivo. We combined chemiluminescence-based H2O2 measurements on a commercially available flow injection analysis (FIA) system with sampling of the analyte using microdialysis probes (MDPs), typically used for measurements in tissue. This allows minimally invasive, quantitative measurements of extracellular H2O2 concentration and dynamics utilizing the chemiluminescent reaction of H2O2 with acridinium ester. By coupling MDPs to the FIA system, measurements are no longer limited to filtered, liquid samples with low viscosity, as sampling via a MDP is based on a dynamic exchange through a permeable membrane with a specific cut-off. This allows continuous monitoring of dynamic changes in H2O2 concentrations, alleviates potential pH effects on the measurements, and allows for flexible application in different media and systems. We give a detailed description of the novel experimental setup and its measuring characteristics along with examples of application in different media and organisms to highlight its broad applicability, but also to discuss current limitations and challenges. The combined FIA-MDP approach for H2O2 quantification was used in different biological systems ranging from marine biology, using the model organism Exaiptasia pallida (light stress induced H2O2 release up to ~ 2.7 µM), over biomedical applications quantifying enzyme dynamics (glucose oxidase in a glucose solution producing up to ~ 60 µM H2O2 and the subsequent addition of catalase to monitor the H2O2 degradation process) and the ability of bacteria to modify their direct environment by regulating H2O2 concentrations in their surrounding media. This was shown by the bacteria Pseudomonas aeruginosa degrading ~ 18 µM background H2O2 in LB-broth. We also discuss advantages and current limitations of the FIA-MDP system, including a discussion of potential cross-sensitivity and interfering chemical species.
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Affiliation(s)
- Maria Moßhammer
- Marine Biological Section, Department of Biology, University of Copenhagen, Denmark
| | - Verena Schrameyer
- Marine Biological Section, Department of Biology, University of Copenhagen, Denmark
| | - Peter Ø Jensen
- Department of Clinical Microbiology, Rigshospitalet, Denmark; Department of Immunology and Microbiology, Costerton Biofilm Center, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Klaus Koren
- Marine Biological Section, Department of Biology, University of Copenhagen, Denmark; Department of Bioscience - Microbiology, University of Aarhus, Denmark.
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of Copenhagen, Denmark; Climate Change Cluster, University of Technology Sydney, Australia.
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Bongaerts J, De Bundel D, Mangelings D, Smolders I, Vander Heyden Y, Van Eeckhaut A. Sensitive targeted methods for brain metabolomic studies in microdialysis samples. J Pharm Biomed Anal 2018; 161:192-205. [DOI: 10.1016/j.jpba.2018.08.043] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 08/20/2018] [Accepted: 08/21/2018] [Indexed: 02/06/2023]
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Phairatana T, Leong CL, Gowers SAN, Patel BA, Boutelle MG. Real-time detection of carboplatin using a microfluidic system. Analyst 2018; 141:6270-6277. [PMID: 27796386 PMCID: PMC5123639 DOI: 10.1039/c6an01446a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel on-line microfluidic assay for the chemotherapy agent carboplatin will allow sensitive detection of the drug directly applied to the tumour as it emerges from the tumour into healthy tissue.
A microfluidic sensor system based on a carbon nanotube-epoxy composite electrode was fabricated to allow detection of the presence of the anti-cancer drug carboplatin in healthy tissue in real time during chemotherapy. Detection of carboplatin was carried out by observing the effects of the drug on the differential pulse voltammetry of free purine bases using a novel carbon nanotube-epoxy composite electrode. In free solution these electrodes performed better than glassy carbon electrodes for oxidation of the free purine bases AMP and GMP, and than DNA-modified carbon nanotube-epoxy composite sensors for detection of carboplatin. On-line carboplatin detection was performed using a computer-controlled microfluidic platform. The methodology for on-line carboplatin detection was optimised in terms of the analysis time and to allow repeated carboplatin measurement using the same electrode. Microdialysis sampling and our microfluidic platform were combined to give a proof-of-concept system for real-time carboplatin detection with a limit of detection of 0.014 μM carboplatin in the sampled media. This paper is dedicated to Craig Lunte's pioneering work in analysis and microdialysis.
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Affiliation(s)
- Tonghathai Phairatana
- Institute of Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand. and Department of Bioengineering, Faculty of Engineering, Imperial College London, London, UK.
| | - Chi Leng Leong
- Department of Bioengineering, Faculty of Engineering, Imperial College London, London, UK.
| | - Sally A N Gowers
- Department of Bioengineering, Faculty of Engineering, Imperial College London, London, UK.
| | - Bhavik Anil Patel
- School of Pharmacy and Biomolecular Sciences, University of Brighton, East Sussex, UK
| | - Martyn G Boutelle
- Department of Bioengineering, Faculty of Engineering, Imperial College London, London, UK.
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Gunawardhana SM, Lunte SM. Continuous monitoring of adenosine and its metabolites using microdialysis coupled to microchip electrophoresis with amperometric detection. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2018; 10:3737-3744. [PMID: 31579297 PMCID: PMC6774626 DOI: 10.1039/c8ay01041b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Rapid monitoring of concentration changes of neurotransmitters and energy metabolites is important for understanding the biochemistry of neurological disease as well as for developing therapeutic options. This paper describes the development of a separation-based sensor using microchip electrophoresis (ME) with electrochemical (EC) detection coupled to microdialysis (MD) sampling for continuous on-line monitoring of adenosine and its downstream metabolites. The device was fabricated completely in PDMS. End-channel electrochemical detection was accomplished using a carbon fiber working electrode embedded in the PDMS. The separation conditions for adenosine, inosine, hypoxanthine, and guanosine were investigated using a ME-EC chip with a 5-cm long separation channel. The best resolution was achieved using a background electrolyte consisting of 35 mM sodium borate at pH 10, 15% dimethyl sulfoxide (DMSO), and 2 mM sodium dodecyl sulphate (SDS), and a field strength of 222 V/cm. Under these conditions, all four purines were separated in less than 85 s. Using a working electrode detection potential of 1.4 vs Ag/AgCl, the limits of detection were 25, 33, 10, and 25 μM for adenosine, inosine, hypoxanthine, and guanosine, respectively. The ME-EC chip was then coupled to microdialysis sampling using a novel all-PDMS microdialysis-microchip interface that was reversibly sealed. This made alignment of the working electrode with the end of the separation channel much easier and more reproducible than could be obtained with previous MD-ME-EC systems. The integrated device was then used to monitor the enzymatic conversion of adenosine to inosine in vitro.
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Affiliation(s)
- Shamal M Gunawardhana
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Susan M Lunte
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
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Zhou Y, Gao L, Peng J, Xing M, Han Y, Wang X, Xu Y, Chang J. Bioglass Activated Albumin Hydrogels for Wound Healing. Adv Healthc Mater 2018; 7:e1800144. [PMID: 29845777 DOI: 10.1002/adhm.201800144] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/01/2018] [Indexed: 12/22/2022]
Abstract
In this study, a novel Bioglass/albumin composite hydrogel with controllable injectability, good adhesiveness, and bioactivity, is developed by utilizing dual-functional bioactive ions released from Bioglass, which on one side controls the gelling time by creating an alkaline environment to regulate the cross-linking reaction between human serum albumin and succinimidyl succinate modified poly(ethylene glycol), and on the other side stimulates wound healing. The composite hydrogel exhibits adhesive property that is superior to clinically used fibrin and cyanoacrylate glues. The gelation time of the composite hydrogel could be regulated via changing the amounts of Bioglass which endows the hydrogel with good injectability. The in vivo experiment confirms that this composite hydrogel has good bioactivity to stimulate angiogenesis and enhance chronic wound healing. Moreover, for the first time, the concentrations of the bioactive ions released from the composite hydrogel in situ are quantified during wound healing using a microdialysis technique, and a correlation of the in vitro and in vivo concentration of ions released from the hydrogel is determined, which is extremely important for understanding the bioactivity mechanisms of Bioglass/bioceramic-based biomaterials and designing biomaterials for tissue regeneration.
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Affiliation(s)
- Yanling Zhou
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Chinese Academy of Sciences; 1295 Dingxi Road Shanghai 200050 China
| | - Long Gao
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Chinese Academy of Sciences; 1295 Dingxi Road Shanghai 200050 China
| | - Jinliang Peng
- School of Pharmacy; Shanghai Jiao Tong University; 800 Dongchuan Road Shanghai 200240 China
| | - Min Xing
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Chinese Academy of Sciences; 1295 Dingxi Road Shanghai 200050 China
| | - Yan Han
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Chinese Academy of Sciences; 1295 Dingxi Road Shanghai 200050 China
| | - Xiaoya Wang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Chinese Academy of Sciences; 1295 Dingxi Road Shanghai 200050 China
| | - Yuhong Xu
- School of Pharmacy; Shanghai Jiao Tong University; 800 Dongchuan Road Shanghai 200240 China
| | - Jiang Chang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Chinese Academy of Sciences; 1295 Dingxi Road Shanghai 200050 China
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Direct sample injection from a syringe needle into a separation capillary. Anal Chim Acta 2018; 1042:133-140. [PMID: 30428980 DOI: 10.1016/j.aca.2018.07.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 07/05/2018] [Accepted: 07/10/2018] [Indexed: 11/22/2022]
Abstract
An automatic micro-injector was developed for electrophoretic analysis of a microlitre amount of clinical samples, enabling injection of the sample from a Hamilton syringe. The outlet of the syringe needle is located directly opposite the inlet of the separation capillary at a defined distance of the order of hundreds of μm in the injection space. During the injection, the background electrolyte is forced out by air from this space and a drop of the sample is forced out of the syringe by a micro-pump so that it is caught at the entrance to the capillary. From the drop the sample is injected into the capillary by applying a negative pressure pulse or simply by spontaneous injection. The injection space is then filled with background electrolyte, which washes away excess sample and separation is commenced. The injector was tested in electrophoretic separation of a model sample with equimolar concentrations of 100 μM NH4+, K+, Na+, Mg2+ and Li+ in a short capillary with total/effective length of 16.5/11.5 cm. The repeatability of the migration time and peak area expressed as the RSD value is 2% and 4%, respectively. The practical applicability of the injector was verified on the determination of the antiparasitic pentamidine in 10 μL of rat plasma. Electrophoretic separation of pentamidine was performed in 100 mM of acetic acid/NaOH at pH 4.55, the sample consumption per analysis is 125 nL, the separation time is 45 s and the attained LOQ using contactless conductivity detection is 8 μM.
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Ngernsutivorakul T, White TS, Kennedy RT. Microfabricated Probes for Studying Brain Chemistry: A Review. Chemphyschem 2018; 19:1128-1142. [PMID: 29405568 PMCID: PMC6996029 DOI: 10.1002/cphc.201701180] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Indexed: 12/13/2022]
Abstract
Probe techniques for monitoring in vivo chemistry (e.g., electrochemical sensors and microdialysis sampling probes) have significantly contributed to a better understanding of neurotransmission in correlation to behaviors and neurological disorders. Microfabrication allows construction of neural probes with high reproducibility, scalability, design flexibility, and multiplexed features. This technology has translated well into fabricating miniaturized neurochemical probes for electrochemical detection and sampling. Microfabricated electrochemical probes provide a better control of spatial resolution with multisite detection on a single compact platform. This development allows the observation of heterogeneity of neurochemical activity precisely within the brain region. Microfabricated sampling probes are starting to emerge that enable chemical measurements at high spatial resolution and potential for reducing tissue damage. Recent advancement in analytical methods also facilitates neurochemical monitoring at high temporal resolution. Furthermore, a positive feature of microfabricated probes is that they can be feasibly built with other sensing and stimulating platforms including optogenetics. Such integrated probes will empower researchers to precisely elucidate brain function and develop novel treatments for neurological disorders.
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Affiliation(s)
| | - Thomas S. White
- Macromolecular Science and Engineering, University of Michigan, 3003E, NCRC Building 28, 2800 Plymouth Rd., Ann Arbor, MI 48109
| | - Robert T. Kennedy
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109
- Department of Pharmacology, University of Michigan, 1150 W. Medical Center Drive, Ann Arbor, MI 48109
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Zaitsu K, Hayashi Y, Murata T, Yokota K, Ohara T, Kusano M, Tsuchihashi H, Ishikawa T, Ishii A, Ogata K, Tanihata H. In Vivo Real-Time Monitoring System Using Probe Electrospray Ionization/Tandem Mass Spectrometry for Metabolites in Mouse Brain. Anal Chem 2018. [DOI: 10.1021/acs.analchem.7b05291] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Kei Zaitsu
- In Vivo Real-time Omics Laboratory, Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Yumi Hayashi
- In Vivo Real-time Omics Laboratory, Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya, 461-8673, Japan
| | - Tasuku Murata
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Kazumi Yokota
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Tomomi Ohara
- In Vivo Real-time Omics Laboratory, Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Maiko Kusano
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Hitoshi Tsuchihashi
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Tetsuya Ishikawa
- Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya, 461-8673, Japan
| | - Akira Ishii
- Department of Legal Medicine and Bioethics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Koretsugu Ogata
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Hiroshi Tanihata
- Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto, 604-8511, Japan
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50
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Saylor RA, Lunte SM. PDMS/glass hybrid device with a reusable carbon electrode for on-line monitoring of catecholamines using microdialysis sampling coupled to microchip electrophoresis with electrochemical detection. Electrophoresis 2018; 39:462-469. [PMID: 28737835 PMCID: PMC5783789 DOI: 10.1002/elps.201700211] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/12/2017] [Accepted: 07/12/2017] [Indexed: 01/16/2023]
Abstract
On-line separations-based sensors employing microdialysis (MD) coupled to microchip electrophoresis (ME) enable the continuous monitoring of multiple analytes simultaneously. Electrochemical detection (EC) is especially amenable to on-animal systems employing MD-ME due to its ease of miniaturization. However, one of the difficulties in fabricating MD-ME-EC systems is incorporating carbon working electrodes into the device. In this paper, a novel fabrication procedure is described for the production of a PDMS/glass hybrid device that is capable of integrating hydrodynamic MD flow with ME-EC using a flow-gated interface and a pyrolyzed photoresist film carbon electrode. This fabrication method enables the reuse of carbon electrodes on a glass substrate, while still maintaining a good seal between the PDMS and glass to allow for pressure-driven MD flow. The on-line MD-ME-EC device was characterized in vitro and in vivo for monitoring analytes in the dopamine metabolic pathway. The ultimate goal is to use this device and associated instrumentation to perform on-animal, near-real time in vivo monitoring of catecholamines.
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Affiliation(s)
- Rachel A. Saylor
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
| | - Susan M. Lunte
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
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