1
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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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2
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Teixidor J, Novello S, Ortiz D, Menin L, Lashuel HA, Bertsch A, Renaud P. On-Demand Nanoliter Sampling Probe for the Collection of Brain Fluid. Anal Chem 2022; 94:10415-10426. [PMID: 35786947 DOI: 10.1021/acs.analchem.2c01577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Continuous fluidic sampling systems allow collection of brain biomarkers in vivo. Here, we propose a new sequential and intermittent sampling paradigm using droplets, called Droplet on Demand (DoD). It is implemented in a microfabricated neural probe and alternates phases of analyte removal from the tissue and phases of equilibration of the concentration in the tissue. It allows sampling droplets loaded with molecules from the brain extracellular fluid punctually, without the long transient equilibration periods typical of continuous methods. It uses an accurately defined fluidic sequence with controlled timings, volumes, and flow rates, and correct operation is verified by the embedded electrodes and a flow sensor. As a proof of concept, we demonstrated the application of this novel approach in vitro and in vivo, to collect glucose in the brain of mice, with a temporal resolution of 1-2 min and without transient regime. Absolute quantification of the glucose level in the samples was performed by direct infusion nanoelectrospray ionization Fourier transform mass spectrometry (nanoESI-FTMS). By adjusting the diffusion time and the perfusion volume of DoD, the fraction of molecules recovered in the samples can be tuned to mirror the tissue concentration at accurate points in time. Moreover, this makes quantification of biomarkers in the brain possible within acute experiments of only 20-120 min. DoD provides a complementary tool to continuous microdialysis and push-pull sampling probes. Thus, the advances allowed by DoD will benefit quantitative molecular studies in the brain, i.e., for molecules involved in volume transmission or for protein aggregates that form in neurodegenerative diseases over long periods.
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Affiliation(s)
- Joan Teixidor
- Microsystems Laboratory 4 (STI-IEM-LMIS4), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Salvatore Novello
- Laboratory of Molecular and Chemical Biology of Neurodegeneration (SV-BMI-LMNN), EPFL, 1015 Lausanne, Switzerland
| | - Daniel Ortiz
- Mass Spectrometry and Elemental Analysis Platform (SB-ISIC-MSEAP), EPFL, 1015 Lausanne, Switzerland
| | - Laure Menin
- Mass Spectrometry and Elemental Analysis Platform (SB-ISIC-MSEAP), EPFL, 1015 Lausanne, Switzerland
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration (SV-BMI-LMNN), EPFL, 1015 Lausanne, Switzerland
| | - Arnaud Bertsch
- Microsystems Laboratory 4 (STI-IEM-LMIS4), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Philippe Renaud
- Microsystems Laboratory 4 (STI-IEM-LMIS4), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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3
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Parker HE, Sengupta S, Harish AV, Soares RRG, Joensson HN, Margulis W, Russom A, Laurell F. A Lab-in-a-Fiber optofluidic device using droplet microfluidics and laser-induced fluorescence for virus detection. Sci Rep 2022; 12:3539. [PMID: 35241725 PMCID: PMC8894408 DOI: 10.1038/s41598-022-07306-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 01/19/2022] [Indexed: 01/10/2023] Open
Abstract
Microfluidics has emerged rapidly over the past 20 years and has been investigated for a variety of applications from life sciences to environmental monitoring. Although continuous-flow microfluidics is ubiquitous, segmented-flow or droplet microfluidics offers several attractive features. Droplets can be independently manipulated and analyzed with very high throughput. Typically, microfluidics is carried out within planar networks of microchannels, namely, microfluidic chips. We propose that fibers offer an interesting alternative format with key advantages for enhanced optical coupling. Herein, we demonstrate the generation of monodisperse droplets within a uniaxial optofluidic Lab-in-a-Fiber scheme. We combine droplet microfluidics with laser-induced fluorescence (LIF) detection achieved through the development of an optical side-coupling fiber, which we term a periscope fiber. This arrangement provides stable and compact alignment. Laser-induced fluorescence offers high sensitivity and low detection limits with a rapid response time making it an attractive detection method for in situ real-time measurements. We use the well-established fluorophore, fluorescein, to characterize the Lab-in-a-Fiber device and determine the generation of [Formula: see text] 0.9 nL droplets. We present characterization data of a range of fluorescein concentrations, establishing a limit of detection (LOD) of 10 nM fluorescein. Finally, we show that the device operates within a realistic and relevant fluorescence regime by detecting reverse-transcription loop-mediated isothermal amplification (RT-LAMP) products in the context of COVID-19 diagnostics. The device represents a step towards the development of a point-of-care droplet digital RT-LAMP platform.
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Affiliation(s)
- Helen E. Parker
- grid.5037.10000000121581746Laser Physics Group, Department of Applied Physics, Royal Institute of Technology (KTH), 100 44 Stockholm, Sweden ,grid.9531.e0000000106567444Scottish Universities Physics Alliance (SUPA), Institute of Photonics and Quantum Sciences, Heriot-Watt University, Edinburgh, EH14 4AS UK
| | - Sanghamitra Sengupta
- grid.5037.10000000121581746Laser Physics Group, Department of Applied Physics, Royal Institute of Technology (KTH), 100 44 Stockholm, Sweden ,grid.417889.b0000 0004 0646 2441AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Achar V. Harish
- grid.5037.10000000121581746Laser Physics Group, Department of Applied Physics, Royal Institute of Technology (KTH), 100 44 Stockholm, Sweden
| | - Ruben R. G. Soares
- grid.5037.10000000121581746Science for Life Laboratory, Division of Nanobiotechnology, Department of Protein Science, Royal Institute of Technology (KTH), 171 65 Solna, Sweden
| | - Haakan N. Joensson
- grid.5037.10000000121581746Science for Life Laboratory, Division of Nanobiotechnology, Department of Protein Science, Royal Institute of Technology (KTH), 171 65 Solna, Sweden
| | - Walter Margulis
- grid.5037.10000000121581746Laser Physics Group, Department of Applied Physics, Royal Institute of Technology (KTH), 100 44 Stockholm, Sweden ,Research Institutes of Sweden (RISE), 164 19 Stockholm, Sweden
| | - Aman Russom
- grid.5037.10000000121581746Science for Life Laboratory, Division of Nanobiotechnology, Department of Protein Science, Royal Institute of Technology (KTH), 171 65 Solna, Sweden ,grid.5037.10000000121581746AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden
| | - Fredrik Laurell
- grid.5037.10000000121581746Laser Physics Group, Department of Applied Physics, Royal Institute of Technology (KTH), 100 44 Stockholm, Sweden
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4
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Wu G, Heck I, Zhang N, Phaup G, Zhang X, Wu Y, Stalla DE, Weng Z, Sun H, Li H, Zhang Z, Ding S, Li DP, Zhang Y. Wireless, battery-free push-pull microsystem for membrane-free neurochemical sampling in freely moving animals. SCIENCE ADVANCES 2022; 8:eabn2277. [PMID: 35196090 PMCID: PMC8865804 DOI: 10.1126/sciadv.abn2277] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 12/29/2021] [Indexed: 06/12/2023]
Abstract
Extensive studies in both animals and humans have demonstrated that high molecular weight neurochemicals, such as neuropeptides and other polypeptide neurochemicals, play critical roles in various neurological disorders. Despite many attempts, existing methods are constrained by detecting neuropeptide release in small animal models during behavior tasks, which leaves the molecular mechanisms underlying many neurological and psychological disorders unresolved. Here, we report a wireless, programmable push-pull microsystem for membrane-free neurochemical sampling with cellular spatial resolution in freely moving animals. In vitro studies demonstrate the sampling of various neurochemicals with high recovery (>80%). Open-field tests reveal that the device implantation does not affect the natural behavior of mice. The probe successfully captures the pharmacologically evoked release of neuropeptide Y in freely moving mice. This wireless push-pull microsystem creates opportunities for neuroscientists to understand where, when, and how the release of neuropeptides modulates diverse behavioral outputs of the brain.
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Affiliation(s)
- Guangfu Wu
- Department of Biomedical Engineering and the Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA
| | - Ian Heck
- Department of Biomedical, Biological, and Chemical Engineering, University of Missouri, Columbia, MO 65211, USA
| | - Nannan Zhang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA
| | - Glenn Phaup
- Center for Precision Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Xincheng Zhang
- Department of Biomedical Engineering and the Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA
| | - Yixin Wu
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
| | - David E. Stalla
- Electron Microscopy Core, University of Missouri, Columbia, MO 65211, USA
| | - Zhengyan Weng
- Department of Biomedical Engineering and the Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA
| | - He Sun
- Department of Biomedical Engineering and the Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA
| | - Huijie Li
- Department of Biomedical Engineering and the Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA
| | - Zhe Zhang
- Department of Biomedical, Biological, and Chemical Engineering, University of Missouri, Columbia, MO 65211, USA
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA
| | - Shinghua Ding
- Department of Biomedical, Biological, and Chemical Engineering, University of Missouri, Columbia, MO 65211, USA
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA
| | - De-Pei Li
- Center for Precision Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Yi Zhang
- Department of Biomedical Engineering and the Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA
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5
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Zhang Y, Kim S, Shi W, Zhao Y, Park I, Brenden C, Iyer H, Jha P, Bashir R, Sweedler JV, Vlasov Y. Droplet-assisted electrospray phase separation using an integrated silicon microfluidic platform. LAB ON A CHIP 2021; 22:40-46. [PMID: 34897344 PMCID: PMC8691365 DOI: 10.1039/d1lc00758k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 10/01/2021] [Indexed: 06/14/2023]
Abstract
We report a silicon microfluidic platform that enables monolithic integration of transparent micron-scale microfluidic channels, an on-chip segmentation of analyte flows into picoliter-volume droplets, and a nano-electrospray ionization emitter that enables spatial and temporal separation of oil and aqueous phases during electro-spray for subsequent mass spectrometry analysis.
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Affiliation(s)
- Yan Zhang
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, IL 61801, USA.
| | - Sungho Kim
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, IL 61801, USA.
| | - Weihua Shi
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, IL 61801, USA.
| | - Yaoyao Zhao
- Department of Chemistry and the Beckman Institute, University of Illinois Urbana Champaign, IL 61801, USA
| | - Insu Park
- Department of Bioengineering, University of Illinois Urbana Champaign, IL 61801, USA
| | - Christopher Brenden
- Department of Bioengineering, University of Illinois Urbana Champaign, IL 61801, USA
| | - Hrishikesh Iyer
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, IL 61801, USA.
| | - Prasoon Jha
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, IL 61801, USA.
| | - Rashid Bashir
- Department of Bioengineering, University of Illinois Urbana Champaign, IL 61801, USA
| | - Jonathan V Sweedler
- Department of Chemistry and the Beckman Institute, University of Illinois Urbana Champaign, IL 61801, USA
| | - Yurii Vlasov
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, IL 61801, USA.
- Department of Bioengineering, University of Illinois Urbana Champaign, IL 61801, USA
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6
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Brain neurochemical monitoring. Biosens Bioelectron 2021; 189:113351. [PMID: 34049083 DOI: 10.1016/j.bios.2021.113351] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 05/05/2021] [Accepted: 05/13/2021] [Indexed: 02/08/2023]
Abstract
Brain neurochemical monitoring aims to provide continuous and accurate measurements of brain biomarkers. It has enabled significant advances in neuroscience for application in clinical diagnostics, treatment, and prevention of brain diseases. Microfabricated electrochemical and optical spectroscopy sensing technologies have been developed for precise monitoring of brain neurochemicals. Here, a comprehensive review on the progress of sensing technologies developed for brain neurochemical monitoring is presented. The review provides a summary of the widely measured clinically relevant neurochemicals and commonly adopted recognition technologies. Recent advances in sampling, electrochemistry, and optical spectroscopy for brain neurochemical monitoring are highlighted and their application are discussed. Existing gaps in current technologies and future directions to design industry standard brain neurochemical sensing devices for clinical applications are addressed.
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7
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Utility of low-cost, miniaturized peristaltic and Venturi pumps in droplet microfluidics. Anal Chim Acta 2021; 1151:338230. [PMID: 33608076 DOI: 10.1016/j.aca.2021.338230] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 01/06/2021] [Accepted: 01/13/2021] [Indexed: 12/15/2022]
Abstract
Many laboratory applications utilizing droplet microfluidics rely on precision syringe pumps for flow generation. In this study, the use of an open-source peristaltic pump primarily composed of 3D printed parts and a low-cost commercial Venturi pump are explored for their use as an alternative to syringe pumps for droplet microfluidics. Both devices provided stable flow (<2% RSD) over a range of 1-7 μL/min and high reproducibility in signal intensity at a droplet generation rate around 0.25 Hz (<3% RSD), which are comparable in performance to similar measurements on standard syringe pumps. As a novel flow generation source for microfluidic applications, the use of the miniaturized Venturi pump was also applied to droplet signal monitoring studies used to measure changes in concentration over time, with average signal reproducibility <4% RSD for both single-stream fluorometric and reagent addition colorimetric applications. These low-cost flow methods provide stable flow sufficient for common droplet microfluidic approaches and can be implemented in a wide variety of simple, and potentially portable, analytical measurement devices.
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8
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Raman R, Rousseau EB, Wade M, Tong A, Cotler MJ, Kuang J, Lugo AA, Zhang E, Graybiel AM, White FM, Langer R, Cima MJ. Platform for micro-invasive membrane-free biochemical sampling of brain interstitial fluid. SCIENCE ADVANCES 2020; 6:eabb0657. [PMID: 32978160 PMCID: PMC7518871 DOI: 10.1126/sciadv.abb0657] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 08/11/2020] [Indexed: 05/11/2023]
Abstract
Neurochemical dysregulation underlies many pathologies and can be monitored by measuring the composition of brain interstitial fluid (ISF). Existing in vivo tools for sampling ISF do not enable measuring large rare molecules, such as proteins and neuropeptides, and thus cannot generate a complete picture of the neurochemical connectome. Our micro-invasive platform, composed of a nanofluidic pump coupled to a membrane-free probe, enables sampling multiple neural biomarkers in parallel. This platform outperforms the state of the art in low-flow pumps by offering low volume control (single stroke volumes, <3 nl) and bidirectional fluid flow (<100 nl/min) with negligible dead volume (<30 nl) and has been validated in vitro, ex vivo, and in vivo in rodents. ISF samples (<1.5 μL) can be processed via liquid chromatography-tandem mass spectrometry. These label-free liquid biopsies of the brain could yield a deeper understanding of the onset, mechanism, and progression of diverse neural pathologies.
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Affiliation(s)
- Ritu Raman
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Erin B Rousseau
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Harvard-MIT Program in Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Michael Wade
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Allison Tong
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Max J Cotler
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Harvard-MIT Program in Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jenevieve Kuang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alejandro Aponte Lugo
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Elizabeth Zhang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ann M Graybiel
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Forest M White
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Robert Langer
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Michael J Cima
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
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9
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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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10
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Reyes-Garcés N, Diwan M, Boyacı E, Gómez-Ríos GA, Bojko B, Nobrega JN, Bambico FR, Hamani C, Pawliszyn J. In Vivo Brain Sampling Using a Microextraction Probe Reveals Metabolic Changes in Rodents after Deep Brain Stimulation. Anal Chem 2019; 91:9875-9884. [DOI: 10.1021/acs.analchem.9b01540] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Nathaly Reyes-Garcés
- Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Mustansir Diwan
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario Canada
| | - Ezel Boyacı
- Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - German A. Gómez-Ríos
- Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Barbara Bojko
- Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - José N. Nobrega
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario Canada
| | - Francis R. Bambico
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario Canada
| | - Clement Hamani
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario Canada
| | - Janusz Pawliszyn
- Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
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11
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Nightingale AM, Leong CL, Burnish RA, Hassan SU, Zhang Y, Clough GF, Boutelle MG, Voegeli D, Niu X. Monitoring biomolecule concentrations in tissue using a wearable droplet microfluidic-based sensor. Nat Commun 2019; 10:2741. [PMID: 31227695 PMCID: PMC6588579 DOI: 10.1038/s41467-019-10401-y] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Accepted: 05/07/2019] [Indexed: 01/02/2023] Open
Abstract
Knowing how biomarker levels vary within biological fluids over time can produce valuable insight into tissue physiology and pathology, and could inform personalised clinical treatment. We describe here a wearable sensor for monitoring biomolecule levels that combines continuous fluid sampling with in situ analysis using wet-chemical assays (with the specific assay interchangeable depending on the target biomolecule). The microfluidic device employs a droplet flow regime to maximise the temporal response of the device, using a screw-driven push-pull peristaltic micropump to robustly produce nanolitre-sized droplets. The fully integrated sensor is contained within a small (palm-sized) footprint, is fully autonomous, and features high measurement frequency (a measurement every few seconds) meaning deviations from steady-state levels are quickly detected. We demonstrate how the sensor can track perturbed glucose and lactate levels in dermal tissue with results in close agreement with standard off-line analysis and consistent with changes in peripheral blood levels.
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Affiliation(s)
- Adrian M Nightingale
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK
| | - Chi Leng Leong
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK
- Department of Bioengineering, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Rachel A Burnish
- Critical Care/ Anaesthesia and Perioperative Medicine Research Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK
| | - Sammer-Ul Hassan
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK
| | - Yu Zhang
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK
| | - Geraldine F Clough
- Faculty of Medicine, University of Southampton, Southampton, SO17 1BJ, UK
| | - Martyn G Boutelle
- Department of Bioengineering, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - David Voegeli
- Faculty of Environmental and Life Sciences, University of Southampton, Southampton, SO17 1BJ, UK
- Now at Department of Sport, Exercise & Health, University of Winchester, Winchester, SO22 4NR, UK
| | - Xize Niu
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK.
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12
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Feng S, Shirani E, Inglis DW. Droplets for Sampling and Transport of Chemical Signals in Biosensing: A Review. BIOSENSORS 2019; 9:E80. [PMID: 31226857 PMCID: PMC6627903 DOI: 10.3390/bios9020080] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 12/14/2022]
Abstract
The chemical, temporal, and spatial resolution of chemical signals that are sampled and transported with continuous flow is limited because of Taylor dispersion. Droplets have been used to solve this problem by digitizing chemical signals into discrete segments that can be transported for a long distance or a long time without loss of chemical, temporal or spatial precision. In this review, we describe Taylor dispersion, sampling theory, and Laplace pressure, and give examples of sampling probes that have used droplets to sample or/and transport fluid from a continuous medium, such as cell culture or nerve tissue, for external analysis. The examples are categorized, as follows: (1) Aqueous-phase sampling with downstream droplet formation; (2) preformed droplets for sampling; and (3) droplets formed near the analyte source. Finally, strategies for downstream sample recovery for conventional analysis are described.
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Affiliation(s)
- Shilun Feng
- School of Engineering, Macquarie University, Sydney, NSW 2109, Australia.
- ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University, Sydney, NSW 2109, Australia.
| | - Elham Shirani
- School of Engineering, Macquarie University, Sydney, NSW 2109, Australia.
| | - David W Inglis
- School of Engineering, Macquarie University, Sydney, NSW 2109, Australia.
- ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University, Sydney, NSW 2109, Australia.
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13
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Feng S, Clement S, Zhu Y, Goldys EM, Inglis DW. Microfabricated needle for hydrogen peroxide detection. RSC Adv 2019; 9:18176-18181. [PMID: 35515258 PMCID: PMC9064684 DOI: 10.1039/c9ra03028j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 05/26/2019] [Indexed: 11/23/2022] Open
Abstract
A microfabricated needle-like probe has been designed and applied for hydrogen peroxide (H2O2) sampling and detection using a commercial, single-step fluorescent H2O2 assay. In this work, droplets of the assay reagent are generated and sent to the needle tip using a mineral-oil carrier fluid. At the needle tip, the sample is drawn into the device through 100 μm long hydrophilic capillaries by negative pressure. The sampled fluid is immediately merged with the assay droplet and carried away to mix and react, producing a sequence of droplets representing the H2O2 concentration as a function of time. We have characterized the assay fluorescence for small variations in the sample volume. With the calibration, we can calculate the concentration of H2O2 in the sampled liquid from the size and intensity of each merged droplet. This is a microfluidic data-logger system for on-site continuous sampling, controlled reaction, signal storage and on-line quantitative detection. It is a useful tool for monitoring dynamic chemical reactions in analytical chemistry and biological applications.
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Affiliation(s)
- Shilun Feng
- School of Engineering, Macquarie University Sydney NSW 2109 Australia
- ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University Sydney NSW 2109 Australia
| | - Sandhya Clement
- ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University Sydney NSW 2109 Australia
- Graduate School of Biomedical Engineering, University of New South Wales Sydney NSW 2052 Australia
| | - Yonggang Zhu
- School of Science, RMIT University Melbourne VIC 3001 Australia
- School of Mechanical Engineering and Automation, Harbin Institute of Technology (Shenzhen) Shenzhen 518055 China
| | - Ewa M Goldys
- ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University Sydney NSW 2109 Australia
- Graduate School of Biomedical Engineering, University of New South Wales Sydney NSW 2052 Australia
| | - David W Inglis
- School of Engineering, Macquarie University Sydney NSW 2109 Australia
- ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP), Macquarie University Sydney NSW 2109 Australia
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14
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Su CK, Ho CC. Online profiling of living rat brain extracellular pH using a pH-Dependent solid phase extraction scheme coupled with microdialysis sampling and inductively coupled plasma mass spectrometry. Anal Chim Acta 2019; 1055:36-43. [DOI: 10.1016/j.aca.2018.12.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 12/07/2018] [Accepted: 12/09/2018] [Indexed: 01/14/2023]
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15
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Zestos AG, Luna-Munguia H, Stacey WC, Kennedy RT. Use and Future Prospects of in Vivo Microdialysis for Epilepsy Studies. ACS Chem Neurosci 2019; 10:1875-1883. [PMID: 30001105 DOI: 10.1021/acschemneuro.8b00271] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Epilepsy is a common neurological disease characterized by recurrent unpredictable seizures. For the last 30 years, microdialysis sampling has been used to measure changes in excitatory and inhibitory neurotransmitter concentrations before, during, and after seizures. These advances have fostered breakthroughs in epilepsy research by identifying neurochemical changes associated with seizures and correlating them to electrophysiological data. Recent advances in methodology may be useful in further delineating the chemical underpinnings of seizures. A new model of ictogenesis has been developed that allows greater control over the timing of seizures that are similar to spontaneous seizures. This model will facilitate making chemical measurements before and during a seizure. Recent advancements in microdialysis sampling, including the use of segmented flow, "fast" liquid chromatography (LC), and capillary electrophoresis with laser-induced fluorescence (CE-LIF) have significantly improved temporal resolution to better than 1 min, which could be used to measure transient, spontaneous neurochemical changes associated with seizures. Microfabricated sampling probes that are markedly smaller than conventional probes and allow for a much greater spatial resolution have been developed. They may allow the targeting of specific brain regions important to epilepsy studies. Coupling microdialysis sampling to optogenetics and light-stimulated release of neurotransmitters may also prove useful for studying epileptic seizures.
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Affiliation(s)
- Alexander G. Zestos
- Department of Chemistry, Center for Behavioral Neuroscience, American University, Washington, D.C. 20016, United States
| | - Hiram Luna-Munguia
- Departamento de Neurobiologia Conductual y Cognitiva, Instituto de Neurobiologia, Universidad Nacional Autonoma de Mexico, Campus UNAM-Juriquilla, Queretaro 76230, Mexico
| | - William C. Stacey
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Robert T. Kennedy
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, United States
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16
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van den Brink FTG, Phisonkunkasem T, Asthana A, Bomer JG, van den Maagdenberg AMJM, Tolner EA, Odijk M. A miniaturized push-pull-perfusion probe for few-second sampling of neurotransmitters in the mouse brain. LAB ON A CHIP 2019; 19:1332-1343. [PMID: 30869670 DOI: 10.1039/c8lc01137k] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Measuring biomolecule concentrations in the brain of living animals, in real time, is a challenging task, especially when detailed information at high temporal resolution is also required. Traditionally, microdialysis probes are used that generally have sampling areas in the order of about 1 mm2, and provide information on concentrations with a temporal resolution of at least several minutes. In this paper, we present a novel miniaturized push-pull perfusion sampling probe that uses an array of small 3 μm-wide sampling channels to sample neurotransmitters at a typical recovery rate of 61%, with a reduced risk of clogging. The added feature to segment the dialysate inside the probe into small water-in-decane droplets enables the detection of concentrations with a temporal resolution of a few seconds. Here we used the probe for in vivo recordings of neurotransmitter glutamate released upon electrical stimulation in the brain of a mouse to demonstrate the feasibility of the probe for real-time neurochemical brain analysis.
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Affiliation(s)
- Floris T G van den Brink
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
| | - Thas Phisonkunkasem
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Ashish Asthana
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
| | - Johan G Bomer
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
| | - Arn M J M van den Maagdenberg
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands and Department of Neurology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Else A Tolner
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands and Department of Neurology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Mathieu Odijk
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
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17
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Park S, Loke G, Fink Y, Anikeeva P. Flexible fiber-based optoelectronics for neural interfaces. Chem Soc Rev 2019; 48:1826-1852. [PMID: 30815657 DOI: 10.1039/c8cs00710a] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Neurological and psychiatric conditions pose an increasing socioeconomic burden on our aging society. Our ability to understand and treat these conditions relies on the development of reliable tools to study the dynamics of the underlying neural circuits. Despite significant progress in approaches and devices to sense and modulate neural activity, further refinement is required on the spatiotemporal resolution, cell-type selectivity, and long-term stability of neural interfaces. Guided by the principles of neural transduction and by the materials properties of the neural tissue, recent advances in neural interrogation approaches rely on flexible and multifunctional devices. Among these approaches, multimaterial fibers have emerged as integrated tools for sensing and delivering of multiple signals to and from the neural tissue. Fiber-based neural probes are produced by thermal drawing process, which is the manufacturing approach used in optical fiber fabrication. This technology allows straightforward incorporation of multiple functional components into microstructured fibers at the level of their macroscale models, preforms, with a wide range of geometries. Here we will introduce the multimaterial fiber technology, its applications in engineering fields, and its adoption for the design of multifunctional and flexible neural interfaces. We will discuss examples of fiber-based neural probes tailored to the electrophysiological recording, optical neuromodulation, and delivery of drugs and genes into the rodent brain and spinal cord, as well as their emerging use for studies of nerve growth and repair.
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Affiliation(s)
- Seongjun Park
- School of Engineering, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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18
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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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19
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Ngernsutivorakul T, Steyer DJ, Valenta AC, Kennedy RT. In Vivo Chemical Monitoring at High Spatiotemporal Resolution Using Microfabricated Sampling Probes and Droplet-Based Microfluidics Coupled to Mass Spectrometry. Anal Chem 2018; 90:10943-10950. [PMID: 30107117 DOI: 10.1021/acs.analchem.8b02468] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
An essential approach for in vivo chemical monitoring is to use sampling probes coupled with analytical methods; however, this method traditionally has limited spatial and temporal resolution. To address this problem, we developed an analytical system that combines microfabricated push-pull sampling probes with droplet-based microfluidics. The microfabricated probe provides spatial resolution approximately 1000-fold better than that of common microdialysis probes. Microfabrication also facilitated integration of an extra channel into the probe for microinjection. We created microfluidic devices and interfaces that allowed manipulation of nanoliter droplet samples collected from the microfabricated probe at intervals of a few seconds. Use of droplet-based microfluidics prevented broadening of collected zones, yielding 6 s temporal resolution at 100 nL/min perfusion rates. Resulting droplets were analyzed by direct infusion nanoelectrospray ionization (nESI) mass spectrometry for simultaneous determination of glutamine, glutamate, γ-aminobutyric acid, and acetylcholine. Use of low infusion rates that enabled nESI (50 nL/min) was critical to allowing detection in the complex samples. Addition of 13C-labeled internal standards to the droplet samples was used for improved quantification. Utility of the overall system was demonstrated by monitoring dynamic chemical changes evoked by microinjection of high potassium concentrations into the brain of live rats. The results showed stimulated neurochemical release with rise times of 15 s. This work demonstrates the potential of coupling microfabricated sampling probes to droplet-based mass spectrometric assays for studying chemical dynamics in a complex microenvironment at high spatiotemporal resolution.
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Affiliation(s)
- Thitaphat Ngernsutivorakul
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 48109 , United States
| | - Daniel J Steyer
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 48109 , United States
| | - Alec C Valenta
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 48109 , United States
| | - Robert T Kennedy
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 48109 , United States.,Department of Pharmacology , University of Michigan , 1150 W. Medical Center Drive , Ann Arbor , Michigan 48109 , United States
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20
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Catterton MA, Dunn AF, Pompano RR. User-defined local stimulation of live tissue through a movable microfluidic port. LAB ON A CHIP 2018; 18:2003-2012. [PMID: 29904762 PMCID: PMC6039252 DOI: 10.1039/c8lc00204e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Many in vivo tissue responses begin locally, yet most in vitro stimuli are delivered globally. Microfluidics has a unique ability to provide focal stimulation to tissue samples with precise control over fluid location, flow rate, and composition. However, previous devices utilizing fixed ports beneath the tissue required manual alignment of the tissue over the ports, increasing the risk of mechanical damage. Here we present a novel microfluidic device that allows the user to define the location of fluid delivery to a living tissue slice without manipulating the tissue itself. The device utilized a two-component SlipChip design to create a mobile port beneath the tissue slice. A culture chamber perforated by an array of ports housed a tissue slice and was separated by a layer of fluorocarbon oil from a single delivery port, fed by a microfluidic channel in the movable layer below. We derived and validated a physical model, based on interfacial tension and flow resistance, to predict the conditions under which fluid delivery occurred without leakage into the gap between layers. Aqueous solution was delivered reproducibly to samples of tissue and gel, and the width of the delivery region was controlled primarily by convection. Tissue slice viability was not affected by stimulation on the device. As a proof-of-principle, we showed that live slices of lymph node tissue could be sequentially targeted for precise stimulation. In the future this device may serve as a platform to study the effects of fluid flow in tissues and to perform local drug screening.
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Affiliation(s)
- Megan A Catterton
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA.
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21
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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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22
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Petit-Pierre G, Colin P, Laurer E, Déglon J, Bertsch A, Thomas A, Schneider BL, Renaud P. In vivo neurochemical measurements in cerebral tissues using a droplet-based monitoring system. Nat Commun 2017; 8:1239. [PMID: 29093476 PMCID: PMC5665973 DOI: 10.1038/s41467-017-01419-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 09/15/2017] [Indexed: 11/09/2022] Open
Abstract
Direct collection of extracellular fluid (ECF) plays a central role in the monitoring of neurological disorders. Current approaches using microdialysis catheters are however drastically limited in term of temporal resolution. Here we show a functional in vivo validation of a droplet collection system included at the tip of a neural probe. The system comprises an advanced droplet formation mechanism which enables the collection of neurochemicals present in the brain ECF at high-temporal resolution. The probe was implanted in a rat brain and could successfully collect fluid samples organized in a train of droplets. A microfabricated target plate compatible with most of the surface-based detection methods was specifically developed for sample analysis. The time-resolved brain-fluid samples are analyzed using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The results provide a time evolution picture of the cerebral tissues neurochemical composition for selected elements known for their involvement in neurodegenerative diseases.
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Affiliation(s)
- Guillaume Petit-Pierre
- Laboratory of Microsystems LMIS4, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| | - Philippe Colin
- Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Estelle Laurer
- Unit of Toxicology, CURML, Lausanne University Hospital, Geneva University Hospitals, Lausanne-Geneva, Switzerland
| | - Julien Déglon
- Unit of Toxicology, CURML, Lausanne University Hospital, Geneva University Hospitals, Lausanne-Geneva, Switzerland
| | - Arnaud Bertsch
- Laboratory of Microsystems LMIS4, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Aurélien Thomas
- Unit of Toxicology, CURML, Lausanne University Hospital, Geneva University Hospitals, Lausanne-Geneva, Switzerland.,Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Bernard L Schneider
- Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Philippe Renaud
- Laboratory of Microsystems LMIS4, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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23
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Zestos AG, Kennedy RT. Microdialysis Coupled with LC-MS/MS for In Vivo Neurochemical Monitoring. AAPS JOURNAL 2017; 19:1284-1293. [PMID: 28660399 DOI: 10.1208/s12248-017-0114-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/13/2017] [Indexed: 10/19/2022]
Abstract
Microdialysis is a powerful sampling technique used to monitor small molecules in vivo. Despite the many applications of microdialysis sampling, it is limited by the method of analyzing the resulting samples. An emerging technique for analysis of microdialysis samples is liquid chromatography-tandem mass spectrometry (LC-MS/MS). This technique is highly versatile, allowing multiplexed analysis of neurotransmitters, metabolites, and neuropeptides. Using LC-MS/MS for polar neurotransmitters is hampered by weak retention reverse phase LC columns. Several derivatization reagents have been utilized to enhance separation and resolution of neurochemicals in dialysate samples including benzoyl chloride (BzCl), dansyl chloride, formaldehyde, ethylchloroformate, and propionic anhydride. BzCl reacts with amine and phenol groups so that many neurotransmitters can be labeled. Besides improving separation on reverse phase columns, this reagent also increases sensitivity. It is available in a heavy form so that it can be used to make stable-isotope labeled internal standard for improved quantification. Using BzCl with LC-MS/MS has allowed for measuring as many as 70 neurochemicals in a single assay. With slightly different conditions, LC-MS/MS has also been used for monitoring endocannabinoids. LC-MS/MS is also useful for neuropeptide assay because it allows for highly sensitive, sequence specific measurement of most peptides. These advances have allowed for multiplexed neurotransmitter measurements in behavioral, circuit analysis, and drug effect studies.
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Affiliation(s)
- Alexander G Zestos
- Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor, Michigan, 48109-1055, USA.,Department of Pharmacology, University of Michigan, 2301 MSRB III, 1150 W. Medical Center Dr., Ann Arbor, Michigan, 48109-1055, USA.,Department of Chemistry, American University, 4400 Massachusetts Avenue, NW, Washington, District of Columbia, 20016, USA
| | - Robert T Kennedy
- Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor, Michigan, 48109-1055, USA. .,Department of Pharmacology, University of Michigan, 2301 MSRB III, 1150 W. Medical Center Dr., Ann Arbor, Michigan, 48109-1055, USA.
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24
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Pompano RR, Chiang AH, Kastrup CJ, Ismagilov RF. Conceptual and Experimental Tools to Understand Spatial Effects and Transport Phenomena in Nonlinear Biochemical Networks Illustrated with Patchy Switching. Annu Rev Biochem 2017; 86:333-356. [PMID: 28654324 PMCID: PMC10852032 DOI: 10.1146/annurev-biochem-060815-014207] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many biochemical systems are spatially heterogeneous and exhibit nonlinear behaviors, such as state switching in response to small changes in the local concentration of diffusible molecules. Systems as varied as blood clotting, intracellular calcium signaling, and tissue inflammation are all heavily influenced by the balance of rates of reaction and mass transport phenomena including flow and diffusion. Transport of signaling molecules is also affected by geometry and chemoselective confinement via matrix binding. In this review, we use a phenomenon referred to as patchy switching to illustrate the interplay of nonlinearities, transport phenomena, and spatial effects. Patchy switching describes a change in the state of a network when the local concentration of a diffusible molecule surpasses a critical threshold. Using patchy switching as an example, we describe conceptual tools from nonlinear dynamics and chemical engineering that make testable predictions and provide a unifying description of the myriad possible experimental observations. We describe experimental microfluidic and biochemical tools emerging to test conceptual predictions by controlling transport phenomena and spatial distribution of diffusible signals, and we highlight the unmet need for in vivo tools.
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Affiliation(s)
- Rebecca R Pompano
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904;
| | - Andrew H Chiang
- Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637;
| | - Christian J Kastrup
- Michael Smith Laboratories and Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada;
| | - Rustem F Ismagilov
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125;
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25
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Ou Y, Weber SG. Numerical Modeling of Electroosmotic Push-Pull Perfusion and Assessment of Its Application to Quantitative Determination of Enzymatic Activity in the Extracellular Space of Mammalian Tissue. Anal Chem 2017; 89:5864-5873. [PMID: 28447456 PMCID: PMC5823015 DOI: 10.1021/acs.analchem.7b00187] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Many sampling methods have been developed to measure the extracellular concentrations of solutes in the extracellular space of mammalian tissue, e.g., brain. However, few have been used to quantitatively study the various processes, such as enzymatic degradation, that determines the fate of these solutes. For a method to be useful in this pursuit, it must be able to (1) perfuse tissue and collect the perfusate for quantitative analysis of the solutes introduced and reaction products produced, (2) control the average residence time of the active solutes, and (3) have the appropriate spatial resolution for the process of interest. Our lab previously developed a perfusion technique based on electroosmosis (EO), called EO push-pull perfusion (EOPPP), that is in principle suitable to meet these needs. However, much like the case for other sampling methods that came before, there are parameters that are needed for quantitative interpretation of data but that cannot be measured easily (or at all). In this paper, we present a robust finite element model that provides a deep understanding of fluid dynamics and mass transport in the EOPPP method, assesses the general applicability of EOPPP to studying enzyme activity in the ECS, and grants a simple approach to data treatment and interpretation to obtain, for example, Vmax and Km for an enzymatic reaction in the extracellular space of the tissue. This model is a valuable tool in optimizing and planning experiments without the need for costly experiments.
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Affiliation(s)
- Yangguang Ou
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260
| | - Stephen G. Weber
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260
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26
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Liu C, Gomez FA. A microfluidic paper‐based device to assess acetylcholinesterase activity. Electrophoresis 2017; 38:1002-1006. [DOI: 10.1002/elps.201600206] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 09/29/2016] [Accepted: 12/11/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Chunye Liu
- Department of Chemistry and Biochemistry California State University Los Angeles CA USA
- School of Pharmacy Xi'an Medical University Xi'an P. R. China
| | - Frank A. Gomez
- Department of Chemistry and Biochemistry California State University Los Angeles CA USA
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27
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Ouimet CM, D’Amico CI, Kennedy RT. Advances in capillary electrophoresis and the implications for drug discovery. Expert Opin Drug Discov 2017; 12:213-224. [PMID: 27911223 PMCID: PMC5521262 DOI: 10.1080/17460441.2017.1268121] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Many screening platforms are prone to assay interferences that can be avoided by directly measuring the target or enzymatic product. Capillary electrophoresis (CE) and microchip electrophoresis (MCE) have been applied in a variety of formats to drug discovery. CE provides direct detection of the product allowing for the identification of some forms of assay interference. The high efficiency, rapid separations, and low volume requirements make CE amenable to drug discovery. Areas covered: This article describes advances in capillary electrophoresis throughput, sample introduction, and target assays as they pertain to drug discovery and screening. Instrumental advances discussed include integrated droplet microfluidics platforms and multiplexed arrays. Applications of CE to assays of diverse drug discovery targets, including enzymes and affinity interactions are also described. Expert opinion: Current screening with CE does not fully take advantage of the throughputs or low sample volumes possible with CE and is most suitable as a secondary screening method or for screens that are inaccessible with more common platforms. With further development, droplet microfluidics coupled to MCE could take advantage of the low sample requirements by performing assays on the nanoliter scale at high throughput.
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Affiliation(s)
- Claire M. Ouimet
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI, 48109, United States
| | - Cara I. D’Amico
- Department of Pharmacology, University of Michigan, 1150 W. Medical Center Dr., Ann Arbor, MI, 48109, United States
| | - Robert T. Kennedy
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI, 48109, United States
- Department of Pharmacology, University of Michigan, 1150 W. Medical Center Dr., Ann Arbor, MI, 48109, United States
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28
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Saha-Shah A, Green CM, Abraham DH, Baker LA. Segmented flow sampling with push-pull theta pipettes. Analyst 2017; 141:1958-65. [PMID: 26907673 DOI: 10.1039/c6an00028b] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We report development of a mobile and easy-to-fabricate theta pipette microfluidic device for segmented flow sampling. The theta pipettes were also used as electrospray emitters for analysis of sub-nanoliter segments, which resulted in delivery of analyte to the vacuum inlet of the mass spectrometer without multiple transfer steps. Theta pipette probes enable sample collection with high spatial resolution due to micron or smaller sized probe inlets and can be used to manipulate aqueous segments in the range of 200 pL to tens of nanoliters. Optimized conditions can enable sampling with high spatial and temporal resolution, suitable for chemical monitoring in biological samples and studies of sample heterogeneity. Intercellular heterogeneity among Allium cepa cells was studied by collecting cytoplasm from multiple cells using a single probe. Extracted cytoplasm was analyzed in a fast and high throughput manner by direct electrospray mass spectrometry of segmented sample from the probe tip.
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Affiliation(s)
- Anumita Saha-Shah
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA.
| | - Curtis M Green
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA.
| | - David H Abraham
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA.
| | - Lane A Baker
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA.
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Su CK, Chen YT, Sun YC. Using on-line solid phase extraction for in vivo speciation of diffusible ferrous and ferric iron in living rat brain extracellular fluid. Anal Chim Acta 2016; 953:87-94. [PMID: 28010747 DOI: 10.1016/j.aca.2016.11.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 11/18/2016] [Accepted: 11/22/2016] [Indexed: 11/26/2022]
Abstract
Exploration of brain extracellular non-protein-bound/diffusible iron species remains a critically important issue in investigations of free radical biology and neurodegenerative diseases. In this study, a facile sample pretreatment scheme, involving poly(vinyl chloride)-metal ion interactions as a selective extraction procedure, was optimized in conjunction with microdialysis (MD) sampling and inductively coupled plasma mass spectrometry (ICP-MS) in cool-plasma mode for in vivo online monitoring of rat brain extracellular Fe(II) and Fe(III) species. Optimization of the system provided detection limits in the range 0.9-6.9 μg Fe L-1, based on a 12-μL microdialysate, for the tested iron species; relative standard deviations of the signal intensities during 7.8 h of continuous measurement were less than 9.4%-sufficient to determine the basal concentrations of rat brain extracellular Fe(II) and Fe(III) species and to describe their dynamic actions. The method's applicability was verified through (i) spike analyses of offline-collected rat brain microdialysates, (ii) determination of the basal Fe(II) and Fe(III) concentrations of living rat brain extracellular fluids, and (iii) monitoring of the dynamic changes in the Fe(II) and Fe(III) concentrations in response to perfusion of a high-K+ medium. This proposed sample pretreatment scheme, based on polymer-metal ion interactions and hyphenation to an MD sampling device and an ICP-MS system, appears to have great practicality for the online monitoring of rat brain extracellular diffusible iron species.
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Affiliation(s)
- Cheng-Kuan Su
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan.
| | - Yi-Ting Chen
- Department of Biomedical Engineering and Environmental Sciences, National Tsing-Hua University, Hsinchu, 30013, Taiwan
| | - Yuh-Chang Sun
- Department of Biomedical Engineering and Environmental Sciences, National Tsing-Hua University, Hsinchu, 30013, Taiwan.
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30
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Microdialysis of Large Molecules. J Pharm Sci 2016; 105:3233-3242. [DOI: 10.1016/j.xphs.2016.08.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/01/2016] [Accepted: 08/22/2016] [Indexed: 12/21/2022]
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31
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Morales-Villagrán A, Pardo-Peña K, Medina-Ceja L, López-Pérez S. A microdialysis and enzymatic reactor sensing procedure for the simultaneous registration of online glutamate measurements at high temporal resolution during epileptiform activity. J Neurochem 2016; 139:886-896. [DOI: 10.1111/jnc.13850] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 08/10/2016] [Accepted: 09/01/2016] [Indexed: 12/01/2022]
Affiliation(s)
- Alberto Morales-Villagrán
- Laboratory of Neurophysiology and Neurochemistry; Department of Cellular and Molecular Biology; CUCBA; University of Guadalajara; Jalisco México
| | - Kenia Pardo-Peña
- Laboratory of Neurophysiology and Neurochemistry; Department of Cellular and Molecular Biology; CUCBA; University of Guadalajara; Jalisco México
| | - Laura Medina-Ceja
- Laboratory of Neurophysiology and Neurochemistry; Department of Cellular and Molecular Biology; CUCBA; University of Guadalajara; Jalisco México
| | - Silvia López-Pérez
- Laboratory of Neurophysiology and Neurochemistry; Department of Cellular and Molecular Biology; CUCBA; University of Guadalajara; Jalisco México
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32
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Stephen TKL, Guillemette KL, Green TK. Analysis of Trinitrophenylated Adenosine and Inosine by Capillary Electrophoresis and γ-Cyclodextrin-Enhanced Fluorescence Detection. Anal Chem 2016; 88:7777-85. [PMID: 27314490 DOI: 10.1021/acs.analchem.6b01796] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Monitoring molecules such as adenosine (Ado) and inosine (Ino) in the central nervous system has enabled the field of neuroscience to correlate molecular concentrations dynamics to neurological function, behavior, and disease. In vivo sampling techniques are commonly used to monitor these dynamics; however, many techniques are limited by the sensitivity and sample volume requirements of currently available detection methods. Here, we present a novel capillary electrophoresis-laser-induced fluorescence detection (CE-LIF) method that analyzes Ado and Ino by derivatization with 2,4,6-trinitrobenzenesulfonic acid to form fluorescent trinitrophenylated complexes of Ado (TNP-Ado) and Ino (TNP-Ino). These complexes exhibit ∼25-fold fluorescence enhancement upon the formation of inclusion complexes with γ-cyclodextrin (γ-CD). Association constants were determined as 4600 M(-1) for Ado and 1000 M(-1) for Ino by CE-LIF. The structure of the TNP-Ado:γ-CD complex was determined by 2D nuclear magnetic resonance (NMR) spectroscopy. Optimal trinitrophenylation reaction conditions and CE-LIF parameters were determined and resulted in the limit of detection of 1.6 μM for Ado and 4 μM for Ino. Ado and Ino were simultaneously quantified in homogenized rat forebrain samples to illustrate application of the technique. Simulated biological samples, desalted by ultrafiltration in the presence γ-CD, were concentrated on-capillary by large-volume sample stacking (LVSS) to achieve detection limits of 32 and 38 nM for TNP-Ado and TNP-Ino, respectively.
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Affiliation(s)
- Terilyn K L Stephen
- Department of Chemistry and Biochemistry and ‡Institute of Arctic Biology, University of Alaska Fairbanks , Fairbanks, Alaska 99775, United States
| | - Katherine L Guillemette
- Department of Chemistry and Biochemistry and ‡Institute of Arctic Biology, University of Alaska Fairbanks , Fairbanks, Alaska 99775, United States
| | - Thomas K Green
- Department of Chemistry and Biochemistry and ‡Institute of Arctic Biology, University of Alaska Fairbanks , Fairbanks, Alaska 99775, United States
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Li Q, Zhu Y, Zhang NQ, Fang Q. Automatic Combination of Microfluidic Nanoliter-Scale Droplet Array with High-Speed Capillary Electrophoresis. Sci Rep 2016; 6:26654. [PMID: 27230468 PMCID: PMC4882528 DOI: 10.1038/srep26654] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 05/04/2016] [Indexed: 12/12/2022] Open
Abstract
In this paper, we developed a novel approach for interfacing a microfluidic two-dimensional droplet array to a high-speed capillary electrophoresis (HSCE) system. Picoliter-scale sample injection (ca. 200 pL) from a nanoliter-scale droplet array covered by nonvolatile oil was automatically achieved using the spontaneous injection mode, without the interference from the cover oil and the need of special droplet extraction interface as in previously reported systems. The system was applied in consecutive separations of 25 different samples of amino acids with a whole separation time less than 15 min, as well as on-line monitoring of in-droplet derivatizing reaction of amino acids by fluorescein isothiocyanate (FITC) over 3 hours. High separation speed (up to 100 samples per hour) and high separation efficiency (up to 9.22 × 10(5) N/m) were achieved.
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Affiliation(s)
- Q Li
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.,Lishui Center for Disease Control and Prevention, Lishui 323000, China
| | - Y Zhu
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - N-Q Zhang
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou 310058, China
| | - Q Fang
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou 310058, China
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Petit-Pierre G, Bertsch A, Renaud P. Neural probe combining microelectrodes and a droplet-based microdialysis collection system for high temporal resolution sampling. LAB ON A CHIP 2016; 16:917-924. [PMID: 26864169 DOI: 10.1039/c5lc01544h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We propose a novel neural probe which combines microfluidic channels with recording and stimulation electrodes. The developed microfabrication approach enables the concentration of every active element such as electrodes and the sampling inlet in close proximity on the same surface. As a first approach, full functional validation is presented in this work (in vivo testing will be presented in the next study). Electrical characterization by impedance spectroscopy is performed in order to assess the electrode properties. An advanced experimental setup enabling the validation of the fluidic functions of the neural probe is also presented. It allowed the achievement of a high temporal resolution (170 ms) during sampling as a result of the integration of a T-junction droplet generator inside the probe. The droplets reached a volume of 0.84 nL and are separated by a non-aqueous phase (perfluoromethyldecalin, PFD). This probe represents an innovative tool for neuroscientists as it can be implanted in precise brain structures while combining electrical stimulation with sampling at a high temporal resolution.
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Affiliation(s)
- Guillaume Petit-Pierre
- Laboratory of Microsystems LMIS4, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland.
| | - Arnaud Bertsch
- Laboratory of Microsystems LMIS4, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland.
| | - Philippe Renaud
- Laboratory of Microsystems LMIS4, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland.
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Lee WH, Ngernsutivorakul T, Mabrouk OS, Wong JMT, Dugan CE, Pappas SS, Yoon HJ, Kennedy RT. Microfabrication and in Vivo Performance of a Microdialysis Probe with Embedded Membrane. Anal Chem 2016; 88:1230-7. [PMID: 26727611 PMCID: PMC5111822 DOI: 10.1021/acs.analchem.5b03541] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Microdialysis sampling is an essential tool for in vivo neurochemical monitoring. Conventional dialysis probes are over 220 μm in diameter and have limited flexibility in design because they are made by assembly using preformed membranes. The probe size constrains spatial resolution and governs the amount of tissue damaged caused by probe insertion. To overcome these limitations, we have developed a method to microfabricate probes in Si that are 45 μm thick × 180 μm wide. The probes contain a buried, U-shaped channel that is 30 μm deep × 60 μm wide and terminates in ports for external connection. A 4 mm length of the probe is covered with a 5 μm thick nanoporous membrane. The membrane was microfabricated by deep reactive ion etching through a porous aluminum oxide layer. The microfabricated probe has cross-sectional area that is 79% less than that of the smallest conventional microdialysis probes. The probes yield 2-20% relative recovery at 100 nL/min perfusion rate for a variety of small molecules. The probe was successfully tested in vivo by sampling from the striatum of live rats. Fractions were collected at 20 min intervals (2 μL) before and after an intraperitoneal injection of 5 mg/kg amphetamine. Analysis of fractions by liquid chromatography-mass spectrometry revealed reliable detection of 14 neurochemicals, including dopamine and acetylcholine, at basal conditions. Amphetamine evoked a 43-fold rise in dopamine, a result nearly identical to a conventional dialysis probe in the same animal. The microfabricated probes have potential for sampling with higher spatial resolution and less tissue disruption than conventional probes. It may also be possible to add functionality to the probes by integrating other components, such as electrodes, optics, and additional channels.
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Affiliation(s)
- Woong Hee Lee
- Department of Chemistry, University of Michigan , 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Thitaphat Ngernsutivorakul
- Department of Chemistry, University of Michigan , 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Omar S Mabrouk
- Department of Chemistry, University of Michigan , 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Jenny-Marie T Wong
- Department of Chemistry, University of Michigan , 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Colleen E Dugan
- Department of Chemistry, University of Michigan , 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Samuel S Pappas
- Department of Neurology, University of Michigan , 1500 East Medical Center Drive, Ann Arbor, Michigan 48109-5316, United States
| | - Hyeun Joong Yoon
- Department of Chemical Engineering, University of Michigan , 2300 Hayward Street, Ann Arbor, Michigan 48109-2136, United States
| | - Robert T Kennedy
- Department of Chemistry, University of Michigan , 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
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36
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López-Valenzuela CL, Morales-Villagrán A, Medina-Ceja L. A novel method for simultaneous glutamate and extracellular activity measurement in brain slices with high temporal resolution. Talanta 2015; 144:1231-8. [PMID: 26452952 DOI: 10.1016/j.talanta.2015.08.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 08/02/2015] [Accepted: 08/05/2015] [Indexed: 11/30/2022]
Abstract
Measurement of neurotransmitters during normal or altered function in cerebral slices could be an important tool to better understand the relationship between biochemical changes and electrophysiological activity. Some attempts of this analysis have been made; however, the current techniques do not have the appropriate time resolution to establish this relationship. The use of electrochemical biosensors has allowed for good time resolution, but problems related to the reduction of signal noise and biofouling of the electrode surface could be an important issue. In this work, we propose a new alternative to simultaneously measure glutamate and electrical activity with a high temporal resolution in brain slices. This approach is based on the use of enzymatic reactors that generate a fluorescent derivative from glutamate that can be measured at high temporal resolution. The results presented here show a reliable measurement of this neurotransmitter in brain slices obtained from intact animals under the effect of a glutamate transporter blocker DL-threo-beta-benzyloxyaspartate as well as the potassium channel blocker 4-aminopyridine. Differences in the levels of glutamate and high frequency and amplitude discharges as an effect of drug administration were found in brain slices obtained from epileptic rats (p<0.05). In conclusion, this method could be used to measure neurotransmitter concentration online at a near physiological temporal resolution, which can then be correlated to the electrical activity that is simultaneously recorded.
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Affiliation(s)
- C L López-Valenzuela
- Laboratory of Neurophysiology and Neurochemistry, Department of Cellular and Molecular Biology, CUCBA, University of Guadalajara, Jalisco, Mexico
| | - A Morales-Villagrán
- Laboratory of Neurophysiology and Neurochemistry, Department of Cellular and Molecular Biology, CUCBA, University of Guadalajara, Jalisco, Mexico.
| | - L Medina-Ceja
- Laboratory of Neurophysiology and Neurochemistry, Department of Cellular and Molecular Biology, CUCBA, University of Guadalajara, Jalisco, Mexico
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Cepeda DE, Hains L, Li D, Bull J, Lentz SI, Kennedy RT. Experimental evaluation and computational modeling of tissue damage from low-flow push-pull perfusion sampling in vivo. J Neurosci Methods 2015; 242:97-105. [PMID: 25614385 PMCID: PMC4331210 DOI: 10.1016/j.jneumeth.2015.01.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 01/05/2015] [Accepted: 01/09/2015] [Indexed: 11/18/2022]
Abstract
BACKGROUND Neurochemical monitoring via sampling probes is valuable for deciphering neurotransmission in vivo. Microdialysis is commonly used; however, the spatial resolution is poor. NEW METHOD Recently push-pull perfusion at low flow rates (50nL/min) has been proposed as a method for in vivo sampling from the central nervous system. Tissue damage from such probes has not been investigated in detail. In this work, we evaluated acute tissue response to low-flow push-pull perfusion by infusing the nuclear stains Sytox Orange and Hoechst 33342 through probes implanted in the striatum for 200min, to label damaged and total cells, respectively, in situ. RESULTS Using the damaged/total labeled cell ratio as a measure of tissue damage, we found that 33±8% were damaged within the dye region around a microdialysis probe. We found that low-flow push-pull perfusion probes damaged 24±4% of cells in the sampling area. Flow had no effect on the number of damaged cells for low-flow push-pull perfusion. Modeling revealed that shear stress and pressure gradients generated by the flow were lower than thresholds expected to cause damage. Comparison with existing methods.Push-pull perfusion caused less tissue damage but yielded 1500-fold better spatial resolution. CONCLUSIONS Push-pull perfusion at low flow rates is a viable method for sampling from the brain with potential for high temporal and spatial resolution. Tissue damage is mostly caused by probe insertion. Smaller probes may yield even lower damage.
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Affiliation(s)
- David E Cepeda
- University of Michigan, Department of Biomedical Engineering, 1101 Beal Ave, Ann Arbor, MI, 49109, United States; University of Michigan, Department of Chemistry, 930N University Ave, Ann Arbor, MI, 48109, United States
| | - Leah Hains
- Wadsworth Center, NYS Department of Health, New York State Bicycle Route 5, Albany, NY 12201, United States
| | - David Li
- University of Michigan, Department of Biomedical Engineering, 1101 Beal Ave, Ann Arbor, MI, 49109, United States
| | - Joseph Bull
- University of Michigan, Department of Biomedical Engineering, 1101 Beal Ave, Ann Arbor, MI, 49109, United States
| | - Stephen I Lentz
- University of Michigan, Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, 6245 Brehm Tower, 1000 Wall Street, Ann Arbor, MI, 48105, United States
| | - Robert T Kennedy
- University of Michigan, Department of Chemistry, 930N University Ave, Ann Arbor, MI, 48109, United States.
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Using copper ions to amplify ROS-mediated fluorescence for continuous online monitoring of extracellular glucose in living rat brain. Biosens Bioelectron 2015; 64:535-41. [DOI: 10.1016/j.bios.2014.09.091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/28/2014] [Accepted: 09/30/2014] [Indexed: 11/17/2022]
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Bucher ES, Wightman RM. Electrochemical Analysis of Neurotransmitters. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2015; 8:239-61. [PMID: 25939038 PMCID: PMC4728736 DOI: 10.1146/annurev-anchem-071114-040426] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Chemical signaling through the release of neurotransmitters into the extracellular space is the primary means of communication between neurons. More than four decades ago, Ralph Adams and his colleagues realized the utility of electrochemical methods for the study of easily oxidizable neurotransmitters, such as dopamine, norepinephrine, and serotonin and their metabolites. Today, electrochemical techniques are frequently coupled to microelectrodes to enable spatially resolved recordings of rapid neurotransmitter dynamics in a variety of biological preparations spanning from single cells to the intact brain of behaving animals. In this review, we provide a basic overview of the principles underlying constant-potential amperometry and fast-scan cyclic voltammetry, the most commonly employed electrochemical techniques, and the general application of these methods to the study of neurotransmission. We thereafter discuss several recent developments in sensor design and experimental methodology that are challenging the current limitations defining the application of electrochemical methods to neurotransmitter measurements.
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Chu J, Hjort K, Larsson A, Dahlin AP. Impact of static pressure on transmembrane fluid exchange in high molecular weight cut off microdialysis. Biomed Microdevices 2014; 16:301-10. [PMID: 24370572 DOI: 10.1007/s10544-013-9833-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
With the interest of studying larger biomolecules by microdialysis (MD), this sampling technique has reached into the ultrafiltration region of fluid exchange, where fluid recovery (FR) has a strong dependence on pressure. Hence in this study, we focus on the fluid exchange across the high molecular weight cut off MD membrane under the influence of the static pressure in the sampling environment. A theoretical model is presented for MD with such membranes, where FR has a linear dependence upon the static pressure of the sample. Transmembrane (TM) osmotic pressure difference and MD perfusion rate decide how fast FR increases with increased static pressure. A test chamber for in vitro MD under static pressure was constructed and validated. It can hold four MD probes under controlled pressurized conditions. Comparison showed good agreement between experiment and theory. Moreover, test results showed that the fluid recovery of the test chamber MD can be set accurately via the chamber pressure, which is controlled by sample injection into the chamber at precise rate. This in vitro system is designed for modelling in vivo MD in cerebrospinal fluid and studies with biological samples in this system may be good models for in vivo MD.
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Affiliation(s)
- Jiangtao Chu
- Department of Engineering Sciences, Uppsala University, Box 534, 751 21, Uppsala, Sweden
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41
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Present state of microchip electrophoresis: state of the art and routine applications. J Chromatogr A 2014; 1382:66-85. [PMID: 25529267 DOI: 10.1016/j.chroma.2014.11.034] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 11/07/2014] [Accepted: 11/12/2014] [Indexed: 12/20/2022]
Abstract
Microchip electrophoresis (MCE) was one of the earliest applications of the micro-total analysis system (μ-TAS) concept, whose aim is to reduce analysis time and reagent and sample consumption while increasing throughput and portability by miniaturizing analytical laboratory procedures onto a microfluidic chip. More than two decades on, electrophoresis remains the most common separation technique used in microfluidic applications. MCE-based instruments have had some commercial success and have found application in many disciplines. This review will consider the present state of MCE including recent advances in technology and both novel and routine applications in the laboratory. We will also attempt to assess the impact of MCE in the scientific community and its prospects for the future.
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Mass spectrometric analysis of spatio-temporal dynamics of crustacean neuropeptides. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1854:798-811. [PMID: 25448012 DOI: 10.1016/j.bbapap.2014.10.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/23/2014] [Accepted: 10/28/2014] [Indexed: 12/13/2022]
Abstract
Neuropeptides represent one of the largest classes of signaling molecules used by nervous systems to regulate a wide range of physiological processes. Over the past several years, mass spectrometry (MS)-based strategies have revolutionized the discovery of neuropeptides in numerous model organisms, especially in decapod crustaceans. Here, we focus our discussion on recent advances in the use of MS-based techniques to map neuropeptides in the spatial domain and monitoring their dynamic changes in the temporal domain. These MS-enabled investigations provide valuable information about the distribution, secretion and potential function of neuropeptides with high molecular specificity and sensitivity. In situ MS imaging and in vivo microdialysis are highlighted as key technologies for probing spatio-temporal dynamics of neuropeptides in the crustacean nervous system. This review summarizes the latest advancement in MS-based methodologies for neuropeptide analysis including typical workflow and sample preparation strategies as well as major neuropeptide families discovered in decapod crustaceans. This article is part of a Special Issue entitled: Neuroproteomics: Applications in Neuroscience and Neurology.
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Guetschow ED, Steyer DJ, Kennedy RT. Subsecond electrophoretic separations from droplet samples for screening of enzyme modulators. Anal Chem 2014; 86:10373-9. [PMID: 25233947 PMCID: PMC4204908 DOI: 10.1021/ac502758h] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
![]()
High-throughput
screening (HTS) using multiwell plates and fluorescence
plate readers is a powerful tool for drug discovery and evaluation
by allowing tens of thousands of assays to be completed in 1 day.
Although this method has been successful, electrophoresis-based methods
for screening are also of interest to avoid difficulties associated
fluorescence assays such as requirements to engineer fluorogenic reactions
and false positives. We have developed a method using droplet microfluidics
to couple multiwell plate-based assays to microchip electrophoresis
(MCE) to screen enzyme modulators. Samples contained in multiwell
plates are reformatted in to plugs with a sample volume of 8 nL segmented
by an immiscible oil. The segmented flow sample streams are coupled
to a hybrid polydimethylsiloxane–glass microfluidic device
capable of selectively extracting the aqueous samples from the droplet
stream and rapidly analyzing by MCE with laser-induced fluorescence
detection. This system was demonstrated by screening a test library
of 140 compounds against using protein kinase A. For each sample in
the screen, two droplets are generated, allowing approximately 6 MCE
injections per sample. Using a 1 s separation at 2000 V/cm, we are
able to analyze 96 samples in 12 min. Separation resolution between
the internal standard, substrate, and product is 1.2 and average separation
efficiency is 16 000 plates/s using real samples. Twenty-five
compounds were identified as modulators during primary screening and
verified using dose–response curves.
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Affiliation(s)
- Erik D Guetschow
- Department of Chemistry, University of Michigan , 930 N. University Avenue, Ann Arbor, Michigan 48109, United States
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DeLaMarre MF, Shippy SA. Development of a Simplified Microfluidic Injector for Analysis of Droplet Content via Capillary Electrophoresis. Anal Chem 2014; 86:10193-200. [DOI: 10.1021/ac502272q] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael F. DeLaMarre
- Department of Chemistry, University of Illinois at Chicago, MC 111, 845 West Taylor Street, Chicago, Illinois 60647, United States
| | - Scott A. Shippy
- Department of Chemistry, University of Illinois at Chicago, MC 111, 845 West Taylor Street, Chicago, Illinois 60647, United States
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Ou Y, Wu J, Sandberg M, Weber SG. Electroosmotic perfusion of tissue: sampling the extracellular space and quantitative assessment of membrane-bound enzyme activity in organotypic hippocampal slice cultures. Anal Bioanal Chem 2014; 406:6455-68. [PMID: 25168111 DOI: 10.1007/s00216-014-8067-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Revised: 07/18/2014] [Accepted: 07/25/2014] [Indexed: 01/30/2023]
Abstract
This review covers recent advances in sampling fluid from the extracellular space of brain tissue by electroosmosis (EO). Two techniques, EO sampling with a single fused-silica capillary and EO push-pull perfusion, have been developed. These tools were used to investigate the function of membrane-bound enzymes with outward-facing active sites, or ectoenzymes, in modulating the activity of the neuropeptides leu-enkephalin and galanin in organotypic-hippocampal-slice cultures (OHSCs). In addition, the approach was used to determine the endogenous concentration of a thiol, cysteamine, in OHSCs. We have also investigated the degradation of coenzyme A in the extracellular space. The approach provides information on ectoenzyme activity, including Michaelis constants, in tissue, which, as far as we are aware, has not been done before. On the basis of computational evidence, EO push-pull perfusion can distinguish ectoenzyme activity with a ~100 μm spatial resolution, which is important for studies of enzyme kinetics in adjacent regions of the rat hippocampus.
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Affiliation(s)
- Yangguang Ou
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
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46
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Fan Y, Lee CY, Rubakhin SS, Sweedler JV. Stimulation and release from neurons via a dual capillary collection device interfaced to mass spectrometry. Analyst 2014; 138:6337-46. [PMID: 24040641 DOI: 10.1039/c3an01010d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Neuropeptides are cell to cell signaling molecules that modulate a wide range of physiological processes. Neuropeptide release has been studied in sample sizes ranging from single cells and neuronal clusters, to defined brain nuclei and large brain regions. We have developed and optimized cell stimulation and collection approaches for the efficient measurement of neuropeptide release from neuronal samples using a dual capillary system. The defining feature is a capillary that contains octadecyl-modified silica nanoparticles on its inner wall to capture and extract releasates. This collection capillary is inserted into another capillary used to deliver solutions that chemically stimulate the cells, with solution flowing up the inner capillary to facilitate peptide collection. The efficiency of peptide collection was evaluated using six peptide standards mixed in physiological saline. The extracted peptides eluted from these capillaries were characterized via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with low femtomole detection limits. Using the capillary collection system in small custom-fabricated culturing chambers, individual cultured neurons and neuronal clusters from the model animal Aplysia californica were stimulated with distinct neuronal secretagogues and the releasates were collected and characterized using MALDI-TOF MS.
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Affiliation(s)
- Yi Fan
- Department of Chemistry and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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47
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Liu W, Wang N, Lin X, Ma Y, Lin JM. Interfacing microsampling droplets and mass spectrometry by paper spray ionization for online chemical monitoring of cell culture. Anal Chem 2014; 86:7128-34. [PMID: 24949883 DOI: 10.1021/ac501678q] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this work, the establishment of a microdialysis-paper spray ionization-mass spectrometry (MS) system was described. A homemade microdialysis module was employed for sampling, and microdroplets were generated at the outlet of the capillary conducting the dialysate. Online MS analysis of each microdroplet was immediately accomplished, interfacing by paper spray ionization. Analytical performance of the method was investigated and improved through the introduction of thinner capillary tubes and the optimization of spray solvent and paper substrate. For microdroplets with concentrated salt at 50 nL, the limit of detection at 0.8 ppm (or 40 pg absolute) and a highest resolution at about 1.5 s were achieved. The integrated system was applied into the online monitoring of glucose concentration in cell culture mediums. A satisfactory linearity of the calibration curve between the relative MS intensity and the glucose concentration was observed. Furthermore, as a model, hormone regulation of the glucose concentration was investigated. This work demonstrated the potential application of the label-free, online "MS sensor" into studies on cellular metabolism.
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Affiliation(s)
- Wu Liu
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Department of Chemistry, Tsinghua University , Beijing 100084, People's Republic of China
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48
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Sun M, Kaplan SV, Gehringer RC, Limbocker RA, Johnson MA. Localized drug application and sub-second voltammetric dopamine release measurements in a brain slice perfusion device. Anal Chem 2014; 86:4151-6. [PMID: 24734992 PMCID: PMC4018083 DOI: 10.1021/ac5008927] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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The
use of fast scan cyclic voltammetry (FSCV) to measure the release
and uptake of dopamine (DA) as well as other biogenic molecules in
viable brain tissue slices has gained popularity over the last 2 decades.
Brain slices have the advantage of maintaining the functional three-dimensional
architecture of the neuronal network while also allowing researchers
to obtain multiple sets of measurements from a single animal. In this
work, we describe a simple, easy-to-fabricate perfusion device designed
to focally deliver pharmacological agents to brain slices. The device
incorporates a microfluidic channel that runs under the perfusion
bath and a microcapillary that supplies fluid from this channel up
to the slice. We measured electrically evoked DA release in brain
slices before and after the administration of two dopaminergic stimulants,
cocaine and GBR-12909. Measurements were collected at two locations,
one directly over and the other 500 μm away from the capillary
opening. Using this approach, the controlled delivery of drugs to
a confined region of the brain slice and the application of this chamber
to FSCV measurements, were demonstrated. Moreover, the consumption
of drugs was reduced to tens of microliters, which is thousands of
times less than traditional perfusion methods. We expect that this
simply fabricated device will be useful in providing spatially resolved
delivery of drugs with minimum consumption for voltammetric and electrophysiological
studies of a variety of biological tissues both in vitro and ex vivo.
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Affiliation(s)
- Meng Sun
- Department of Chemistry and R. N. Adams Institute for Bioanalytical Chemistry, University of Kansas , Lawrence, Kansas 66045 United States
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49
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Romanova EV, Aerts JT, Croushore CA, Sweedler JV. Small-volume analysis of cell-cell signaling molecules in the brain. Neuropsychopharmacology 2014; 39:50-64. [PMID: 23748227 PMCID: PMC3857641 DOI: 10.1038/npp.2013.145] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 04/26/2013] [Accepted: 05/06/2013] [Indexed: 12/19/2022]
Abstract
Modern science is characterized by integration and synergy between research fields. Accordingly, as technological advances allow new and more ambitious quests in scientific inquiry, numerous analytical and engineering techniques have become useful tools in biological research. The focus of this review is on cutting edge technologies that aid direct measurement of bioactive compounds in the nervous system to facilitate fundamental research, diagnostics, and drug discovery. We discuss challenges associated with measurement of cell-to-cell signaling molecules in the nervous system, and advocate for a decrease of sample volumes to the nanoliter volume regimen for improved analysis outcomes. We highlight effective approaches for the collection, separation, and detection of such small-volume samples, present strategies for targeted and discovery-oriented research, and describe the required technology advances that will empower future translational science.
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Affiliation(s)
- Elena V Romanova
- Beckman Institute for Advanced Science and Technology and the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jordan T Aerts
- Beckman Institute for Advanced Science and Technology and the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Callie A Croushore
- Beckman Institute for Advanced Science and Technology and the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jonathan V Sweedler
- Beckman Institute for Advanced Science and Technology and the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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50
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Hu JB, Chen SY, Wu JT, Chen YC, Urban PL. Automated system for extraction and instantaneous analysis of millimeter-sized samples. RSC Adv 2014. [DOI: 10.1039/c3ra48023b] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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