Wir danken Dr. Aaron P. Fox an der Universität von Chicago, in dessen Labor das Protokoll wurde ursprünglich entworfen, und William Roden (Saint Louis University) für die Weiterentwicklung des Protokolls. Wir danken der Whitehall-Stiftung und National Science Foundation für die Unterstützung.

Teil 1: Carbon Fiber Preparation <ol><li> Cut ein Bündel von Kohlenstoff-Fasern (wir verwenden 7μm Durchmesser) auf eine Länge ~ 1,25 X die Länge der Kapillare Pipette wird. </li><li> Entfernen Sie die Dimensionierung durch Kochen ~ 100 ml Aceton in einen Behälter und Zugabe der Fasern zu den heißen, siedendem Aceton für 30 Minuten oder länger. </li><li> Entfernen Fasern aus dem warmen Aceton, und in ein sauberes Becherglas mit 50-100 ml frischem Aceton. </li><li> Trockene Fasern, indem das Bündel auf einer offenen 150 mm Petrischale und lufttrocken Nacht. </li></ol> Teil 2: Feuerpolieren Glaskapillaren <ol><li> Fire-polnisch jeder Kapillare (wir benutzen Mikro-Hämatokrit-Kapillarröhrchen, 1,5 mm Außendurchmesser, 1,3 mm Innendurchmesser, 7,5 cm lang), indem das Rohr in der Mitte mit einer Pinzette und Freilegen der Ende der flame.Rotate das Rohr über 3-mal, während in der Flamme. </li><li> Kehren Sie die Röhrchen und setzen Sie das andere Ende in die Flamme wieder rotierenden 3-mal. </li><li> Legen Sie die feuerpolierte Rohre in eine Glasschale und Transfer zum Ofen, bis sie bereit sind, mit Carbon-Fasern gefüllt werden sollen. </li></ol> Teil 3: Threading einem Kohlefaser in einer Kapillare <ol><li> Ähnlich wie bei den Beschreibungen von Machado et al. (2008) und Mundroff und Wightman (2002), saugen die Faser in das Glasrohr mit Kunststoffschlauch verbunden, um ein Vakuum mit einem Filter. </li><li> Schneiden Sie die Faser mit Hilfe eines scalpel.Leave ¼ inch der Faser aus dem Rohr. </li></ol> Teil 4: Pulling Pipette-Fiber in einer Elektrode Puller <ol><li> Legen Sie Kapillare in die Elektrode Abzieher (wir verwenden Narishige Japan Modell PP-830) und ziehen Sie die Regler in die Kapillare in Position zu halten. </li><li> Bearbeiten Sie die Schalter auszuführen zwei Züge, setzen Sie auf die optimale puller Einstellungen. </li><li> Nachdem die Pipette in der Hälfte gezogen wird, trennen Sie die zwei Hälften, indem die nackten Faser in der Mitte mit einer Schere. </li><li> Entfernen Sie jede Elektrode Hälfte und Zug auf die hervorstehenden Fasern zu brechen das Glas seal.Trim die Faser mit einer Schere, so dass nur 1 / 8 Zoll von Faser außerhalb der Röhre bleibt. </li><li> Wiederholen Sie die Schritte 1-4, bis etwa 16-Faser-Elektroden gezogen werden. </li></ol> Teil 5: Making Epoxy-Glass Seal <ol><li> Erhitzen Sie eine vorgefertigte Aliquot Epoxy auf einer heißen Platte gesetzt bis 55 ° C für 6 Minuten in einem Abzug. </li><li> Während Epoxidharz Heizung, wrap ~ 16 des gezogenen Elektroden in ein Bündel mit Klebeband. </li><li> Nach dem Epon Resin für 6 Minuten erwärmt ist, fügen Sie 0,7 Gramm XOF MPDA zu den heißen Epon Resin (14%, w / v). Mix durch Schwenken der Flasche. </li><li> Tauchen Sie die Bündel von Elektroden in die heiße Epoxy plus Härter solution.After ca. 20 Sekunden, eine ausreichende Menge an Epoxid wird das Glas Tipps über Kapillarwirkung geben. </li><li> Lösen Sie die Bündel, Ort Elektroden auf Karton mit Schlitzen und Ort dieses Fach in einem Ofen auf 100 ° F. </li><li> Nach mindestens 48 Stunden, überprüfen Sie jede Elektrode unter einem Präpariermikroskop microscope.Discard Elektroden, die nicht mit Epoxy hat zu füllen, haben eine zertrümmerte Spitze, haben mehr als eine Faser, etc.After Inspektion jede Elektrode, legen Sie sie wieder auf dem Karton Inhaber und zurück in den oven.Electrodes sind in der Regel gut für etwa 1 Monat nach der Herstellung. </li></ol> Teil 6: Schneiden Sie die Carbon Fiber <ol><li> Legen Sie Kohlefaser Elektrode vorsichtig auf einen Objektträger mit Teflonband. </li><li> Visualisieren Sie die Spitze unter einem Binokular. </li><li> Verwenden Sie ein sauberes Skalpell senkrecht quer durch die Kohlefaser eine ebene, saubere Oberfläche für die Platzierung der Kohlefaser gegen eine Zelle zu verlassen. </li></ol>

<ol>
	<li>Mundorf, M. L., Wightman, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amperometry+and+cyclic+voltammetry+with+carbon+fiber+microelectrodes+at+single+cells.">Amperometry and cyclic voltammetry with carbon fiber microelectrodes at single cells.</a> Curr Protocols in Neurosci. 6 (14), 1-6 (2002).</li><li>Machado, D. J., Montesinos, M. S., Borges, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Good+practices+in+single-cell+amperometry.">Good practices in single-cell amperometry.</a> Methods in Molec. Biol. 440, 297-313 (2008).</li></ol>

Dieses Protokoll beschreibt, wie zu generieren und zu schneiden amperometrischen Elektroden. Während amperometrische Aufnahmen, ist eine Kohlefaser-Elektrode gegen die Oberfläche eines sekretorischen Zelle platziert. Exozytotische Aktivität wird als amperometrische Spikes, die die elektrochemische Strom, der durch den Transfer von Elektronen nach der Oxidation der Katecholamine verursacht zeigt beobachtet. Mit etwas Übung machen und Schneiden amperometrischen Elektroden kann Geräuschpegel erheblich über viele der ...

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Epoxy Hardener 1,3-phenylene-diamene flakes</td>
<td>Reagent</td>
<td>Sigma Aldrich</td>
<td>P23954-100G04 716AJ</td>
<td>Aliquots are stored in a dessicator and should not be exposed to light.</td>
</tr>
<tr>
<td>Carbon Fibers</td>
<td>Material</td>
<td>Goodfellow</td>
<td>C005725</td>
<td>&nbsp;</td>
<tr>
<td>Micro-Hematocrit Capillary Tubes</td>
<td>Material</td>
<td>Fisher</td>
<td>NC9836768</td>
<td>&nbsp;</td>
<tr>
<td>Epoxy Resin</td>
<td>Reagent</td>
<td>Miller-Stephenson</td>
<td>Epon Resin 828</td>
<td>&nbsp;</td>
<tr>
<td>Dissecting Microscope</td>
<td>Instrument</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Electrode Puller</td>
<td>Instrument</td>
<td>Narishige Japan</td>
<td>PP-830</td>
<td>1st pull = 24.8 degrees C; 2nd pull = 62.7 degrees C</td>
</tr>
<tr>
<td>Oven</td>
<td>Instrument</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>set to 100 degrees F.</td>
</tr>
<tr>
<td>Hot plate</td>
<td>Instrument</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>set to 55 degrees C</td>
</tr>		</tbody>
		</table>
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fabrication of amperometric electrodes

Carbon-Elektroden sind entscheidend für den Nachweis von Katecholamin Entlassung aus dem Vesikel in einzelnen Zellen für Amperometrie Messungen. Hier beschreiben wir die Techniken erforderlich, um geräuscharm (&lt;0,5 pA) Elektroden zu erzeugen. Die Techniken wurden aus veröffentlichten Beschreibungen wurden von früheren Forschern (1,2) modifiziert. Die Elektroden sind durch Herstellung von Kohlenstoff-Fasern und Einfädeln sie einzeln in jede Kapillare mit Hilfe eines Vakuums mit einem Filter, um die Faser absaugen gemacht. Anschließend wird die Kapillare mit Faser durch eine Elektrode Abziehers, wodurch zwei Hälften, die jeweils mit einer feinen Spitze. Die Elektroden werden in heißem, flüssigem Epoxidharz mit Härter gemischt, um ein Epoxid-Glas-Siegel erstellen getaucht. Schließlich sind die Elektroden in einen Ofen gelegt, um das Epoxidharz zu heilen. Sorgfältige Behandlung der Elektroden ist entscheidend, um sicherzustellen, dass sie gemacht werden konsequent und ohne Beschädigung. Dieses Protokoll zeigt, wie in der Herstellung und schneiden amperometrischen Elektroden für die Aufzeichnung von einzelnen Zellen.

Watch this Scientific Journal Video about Fabrication of Amperometric Electrodes at JoVE.com

Fabrication of Amperometric Electrodes

Dieses Protokoll beschreibt, wie Kohlefaser Elektroden zu erzeugen. Die Elektroden werden anschließend verwendet, um Katecholaminausschüttung von Vesikeln mit Kohlefaser Amperometrie erkennen.

Herstellung von amperometrische Elektroden

Carbon fiber electrodes are crucial for the detection of catecholamine release from vesicles in single cells for amperometry measurements.  Here, we ...

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Analytical Chemistry

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Unit 1

Electrochemical Analyses and Redox Titration

SCIENTISTS IN ACTION

14.3K Aufrufe.  Saint Louis University School of Medicine. Dieses Protokoll beschreibt, wie Kohlefaser Elektroden zu erzeugen. Die Elektroden werden anschließend verwendet, um Katecholaminausschüttung von Vesikeln mit Kohlefaser Amperometrie erkennen.

Serie: Fabrication of Amperometric Electrodes

Application of Light-cured Dental Adhesive Resin for Mounting Electrodes or Microdialysis Probes in Chronic Experiments

In chronic recording experiments, self-curing dental acrylic resins have been used as a mounting base of electrodes or microdialysis-probes. Since these acrylics do not bond to the bone, screws have been used as anchors. However, in small experimental animals like finches or mouse, their craniums are very fragile and can not successfully hold the anchors. In this report, we propose a new application of light-curing dental resins for mounting base of electrodes or microdialysis probes in chronic experiments. This material allows direct bonding to the cranium. Therefore, anchor screws are not required and surgical field can be reduced considerably. Past experiences show that the bonding effect maintains more than 2 months. Conventional resin's window of time when the materials are pliable and workable is a few minutes. However, the window of working time for these dental adhesives is significantly wider and adjustable.

In this report, we propose a new application of light-curing dental resins for mounting base of electrodes or microdialysis probes in chronic experiments. This material allows direct bonding to the cranium.

Anwendung von Licht-gehärteten Dental Adhesive Resin für Montage-Elektroden oder Mikrodialysesonden in Chronic Experimente

In chronic recording experiments, self-curing dental acrylic resins have been used as a mounting base of electrodes or microdialysis-probes. Since these ...

Forschung

Biologie

Patterning Cells on Optically Transparent Indium Tin Oxide Electrodes

The ability to exercise precise spatial and temporal control over cell-surface interactions is an important prerequisite to the assembly of multi-cellular constructs serving as in vitro mimics of native tissues.  In this study, photolithography and wet etching techniques were used to fabricate individually addressable indium tin oxide (ITO) electrodes on glass substrates.  The glass substrates containing ITO microelectrodes were modified with poly(ethylene glycol) (PEG) silane to make them protein and cell resistive.  Presence of insulating PEG molecules on the electrode surface was verified by cyclic voltammetry employing potassium ferricyanide as a redox reporter molecule.  Importantly, the application of reductive potential caused desorption of the PEG layer, resulting in regeneration of the conductive electrode surface and appearance of typical ferricyanide redox peaks.    Application of reductive potential also corresponded to switching of ITO electrode properties from cell non-adhesive to cell-adhesive. Electrochemical stripping of PEG-silane layer from ITO microelectrodes allowed for cell adhesion to take place in a spatially defined fashion, with cellular patterns corresponding closely to electrode patterns.  Micropatterning of several cell types was demonstrated on these substrates.   In the future, the control of the biointerfacial properties afforded by this method will allow to engineer cellular microenvironments through the assembly of three or more cell types into a precise geometric configuration on an optically transparent substrate.

Non-fouling PEG silane monolayer was desorbed from individually addressable ITO electrodes on glass by application of a reductive potential. Electrochemical stripping of PEG-silane layer from ITO microelectrodes allowed for cell adhesion to take place in a spatially defined fashion, with cellular patterns corresponding closely to electrode patterns.

Patterning Cells auf optisch transparenten Indium-Zinn-Oxid-Elektroden

The ability to exercise precise spatial and temporal control over cell-surface interactions is an important prerequisite to the assembly of multi-cellular ...

Fabrication of a Microfluidic Device for the Compartmentalization of Neuron Soma and Axons

In this video, we demonstrate the technique of soft lithography with polydimethyl siloxane (PDMS) which we use to fabricate a microfluidic device for culturing neurons. Previously, a silicon wafer was patterned with the design for the neuron microfluidic device using SU-8 and photolithography to create a master mold, or what we simply refer to as a "master". Next, we pour the silicon polymer PDMS on top of the master which is then cured by heating the PDMS to 80&deg;C for 1 hour. The PDMS forms a negative mold of the device. The PDMS is then carefully cut and lifted away from the master. Holes are punched where the reservoirs will be and the excess PDMS trimmed away from the device. Nitrogen is used to blow away any excess debris from the device. At this point the devices are now ready for use and can either bonded to corning No. 1 cover glass with a plasma sterilizer/cleaner or can be reversibly bound to the cover glass by simply placing the device on top of the cover glass. The reversible bonding of the device to glass is covered in a separate video and requires first that the device be sterilized either with 70% ethanol or by autoclaving. Plasma treating sterilizes the devices so no further treatment is necessary. It is, however, important, when plasma-treating the devices, to add liquid to the devices within 10 minutes of the plasma treatment while the surfaces are still hydrophilic. Waiting longer than 10 minutes to add liquid to the device makes it difficult for the liquid to enter the device. The neuron devices are typically plasma-bound to cover glass and 0.5 mg/ml poly-L-lysine (PLL) in pH 8.5 borate buffer is immediately added to the device. After a minimum of 3 hours incubating with PLL, the devices are washed with dH2O water a minimum of 3 times with at least 15 minutes between each wash. Next, the water is removed and fresh media is added to the device. At this point the device is ready for use. It is important to remember at this point to never remove all the media from the device. Always leave media in the main channel.

In this video we demonstrate the technique of soft lithography with polydimethyl siloxane (PDMS) which we use to farbricate a microfluidic device for culturing neurons.

Herstellung eines mikrofluidischen Vorrichtung für die Abschottung der Neuron Soma und Axonen

In this video, we demonstrate the technique of soft lithography with polydimethyl siloxane (PDMS) which we use to fabricate a microfluidic device for ...

PDMS Device Fabrication and Surface Modification

PDMS Bauelementherstellung und Oberflächenmodifizierung

Non-plasma Bonding of PDMS for Inexpensive Fabrication of Microfluidic Devices

In this video, we demonstrate how to use the neuron microfluidic device without plasma bonding.  In some cases it may be desirable to reversibly bond devices to the Corning No. 1 cover glass.  This could be due, perhaps, to a plasma cleaner not being available.  In other instances, it may be desirable to remove the device from the glass after the culturing of neurons for certain types of microscopy or for immunostaining, though it is not necessary to remove the device for immunostaining since the neurons can be stained in the device.  Some researchers, however, still prefer to remove the device.  In this case, reversible bonding of the device to the cover glass makes that possible.  There are some disadvantages to non-plasma bonding of the devices in that not as tight of a seal is formed.  In some cases axons may grow under the grooves rather than through them.  Also, because the glass and PDMS are hydrophobic, liquids do not readily enter the device making it necessary at times to force media and other reagents into the device.  Liquids will enter the device via capillary action, but it takes significantly longer as compared to devices that have been plasma bonded.  The plasma cleaner creates temporary hydrophilic charges on the glass and device that facilitate the flow of liquids through the device after bonding within seconds.  For non-plasma bound devices, liquid flow through the devices takes several minutes.  It is also important to note that the devices to be used with non-plasma bonding need to be sterilized first, whereas plasma treated devices do not need to be sterilized prior to use because the plasma cleaner will sterilize them.

In this video we demonstrate how to use the neuron microfluidic device without plasma bonding.

Non-Plasma-Bonding von PDMS für preiswerte Herstellung von Mikrofluidik-Geräte

In this video, we demonstrate how to use the neuron microfluidic device without plasma bonding.  In some cases it may be desirable to reversibly bond ...

Fabrication of the Thermoplastic Microfluidic Channels

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using polymer/nanoparticle composite microscale lysis and solid phase extraction columns. The recovered samples are concentrated, small volume samples that are PCRable, without any additional cleanup. Here, we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then, we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns. We demonstrate grafting and polymerization of a carbon nanotube/polymer composite column for bacterial cell lysis. We then show the lysis process followed by solid phase extraction of nucleic acids from the sample on chip using a silica/polymer composite column. The attached protocols contain detailed instructions on how to make both lysis and solid phase extraction columns.

Here we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns.

Die Herstellung der thermoplastischen Mikrofluidikkanälen

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using ...

Making Patch-pipettes and Sharp Electrodes with a Programmable Puller

Glass microelectrodes (also called pipettes) have been a workhorse of electrophysiology for decades. Today, such pipettes are made from glass capillaries using a programmable puller. Such instruments heat the capillary using either a metal filament or a laser and draw out the glass using gravity, a motor or both. Pipettes for patch-clamp recording are formed using only heat and gravity, while sharp electrodes for intracellular recording use a combination of heat, gravity, and a motor. The procedure used to make intracellular recording pipettes is similar to that used to make injection needles for a variety of applications, including cRNA injection into Xenopus oocytes. In general, capillary glass &lt;1.2 mm in diameter is used to make pipettes for patch clamp recording, while narrower glass is used for intracellular recording (outer diameter = 1.0 mm). For each tool, the puller is programmed slightly differently. This video shows how to make both kinds of recording pipettes using pre-established puller programs.

This video shows how to use a programmable puller to make patch pipettes and sharp electrodes for electrophysiology. The same procedure can be used to make a variety of glass tools, including injection needles.

Machen Patch-Pipetten und Sharp Elektroden mit einem programmierbaren Puller

Glass microelectrodes (also called pipettes) have been a workhorse of electrophysiology for decades.  Today, such pipettes are made from glass capillaries ...

Fabrication of Myogenic Engineered Tissue Constructs

Despite the fact that electronic pacemakers are life-saving medical devices, their long-term performance in pediatric patients can be problematic owing to the restrictions imposed by a child's small size and their inevitable growth. Consequently, there is a genuine need for innovative therapies designed specifically for pediatric patients with cardiac rhythm disorders. We propose that a conductive biological alternative consisting of a collagen-based matrix containing autologously-derived cells could better adapt to growth, reduce the need for recurrent surgeries, and greatly improve the quality of life for these patients. In the present study, we describe a procedure for incorporating primary skeletal myoblast cell cultures within a hydrogel matrix to fashion a surgically-implantable tissue construct that will serve as an electrical conduit between the upper and lower chambers of the heart. Ultimately, we anticipate using this type of engineered tissue to restore atrioventricular electrical conduction in children with complete heart block. In view of that, we isolate myoblasts from the skeletal muscles of neonatal Lewis rats and plate them onto laminin-coated tissue culture dishes using a modified version of established protocols[2, 3]. After one to two days, cultured cells are collected and mixed with antibiotics, type 1 collagen, Matrigel&trade;, and NaHCO3. The result is a viscous, uniform solution that can be cast into a mold of nearly any shape and size[1, 4, 5]. For our tissue constructs, we employ type 1 collagen isolated from fetal lamb skin using standard procedures[6]. Once the tissue has solidified at 37&deg;C, culture media is carefully added to the plate until the construct is submerged. The engineered tissue is then allowed to further condense through dehydration for 2 more days, at which point it is ready for in vitro assessment or surgical-implantation.

Here, we demonstrate fabrication of collagen-based, tissue constructs containing skeletal myoblasts. These 3-D engineered constructs may be used to replace or repair tissues in vivo. For our purposes, we have designed these as an atrioventricular electrical conduit for the repair of complete heart block[1].

Herstellung von Myogenic Engineered Tissue Konstrukte

Despite the fact that electronic pacemakers are life-saving medical devices, their long-term performance in pediatric patients can be problematic owing to ...

Fabrication and Operation of an Oxygen Insert for Adherent Cellular Cultures 

Oxygen is a key modulator of many cellular pathways, but current devices permitting in vitro oxygen modulation fail to meet the needs of biomedical research. The hypoxic chamber offers a simple system to control oxygenation in standard culture vessels, but lacks precise temporal and spatial control over the oxygen concentration at the cell surface, preventing its application in studying a variety of physiological phenomena. Other systems have improved upon the hypoxic chamber, but require specialized knowledge and equipment for their operation, making them intimidating for the average researcher. A microfabricated insert for multiwell plates has been developed to more effectively control the temporal and spatial oxygen concentration to better model physiological phenomena found in vivo. The platform consists of a polydimethylsiloxane insert that nests into a standard multiwell plate and serves as a passive microfluidic gas network with a gas-permeable membrane aimed to modulate oxygen delivery to adherent cells. The device is simple to use and is connected to gas cylinders that provide the pressure to introduce the desired oxygen concentration into the platform. Fabrication involves a combination of standard SU-8 photolithography, replica molding, and defined PDMS spinning on a silicon wafer. The components of the device are bonded after surface treatment using a hand-held plasma system. Validation is accomplished with a planar fluorescent oxygen sensor. Equilibration time is on the order of minutes and a wide variety of oxygen profiles can be attained based on the device design, such as the cyclic profile achieved in this study, and even oxygen gradients to mimic those found in vivo. The device can be sterilized for cell culture using common methods without loss of function. The device's applicability to studying the in vitro wound healing response will be demonstrated.

Fabrication and Operation of an Oxygen Insert for Adherent Cellular Cultures

Fabrication and validation of an add-on platform that offers enhanced control over the spatial and temporal oxygenation in a 6-well plate. The device is adaptable to a number of culture systems and can be used to investigate the effects of oxygen on wound healing.

Herstellung und Betrieb eines Oxygen Insert für adhärente Zellkulturen

Oxygen is a key modulator of many cellular pathways, but current devices permitting in vitro oxygen modulation fail to meet the needs of biomedical ...

Fabrication and Use of MicroEnvironment microArrays (MEArrays)

The interactions between cells and their surrounding microenvironment have functional consequences for cellular behaviour. On the single cell level, distinct microenvironments can impose differentiation, migration, and proliferation phenotypes, and on the tissue level the microenvironment processes as complex as morphogenesis and tumorigenesis1. Not only do the cell and molecular contents of microenvironments impact the cells within, but so do the elasticity2 and geometry3 of the tissue. Defined as the sum total of cell-cell, -ECM, and -soluble factor interactions, in addition to physical characteristics, the microenvironment is complex. The phenotypes of cells within a tissue are partially due to their genomic content and partially due to the combinatorial interactions with the microenviroment. A major challenge is to link specific combinations of microenvironmental components with distinctive behaviours.
Here, we present the microenvironment microarray (MEArray) platform for cell-based functional screening of interactions with combinatorial microenvironments4. The method allows for simultaneous control of the molecular composition and the elastic modulus, and combines the use of widely available microarray and micropatterning technologies. MEArray screens require as few as 10,000 cells per array, which facilitates functional studies of rare cell types such as adult progenitor cells. A limitation of the technology is that entire tissue microenvironments cannot be completely recapitulated on MEArrays. However, comparison of responses in the same cell type to numerous related microenvironments, for instance pairwise combinations of ECM proteins that characterize a given tissue, will provide insights into how microenvironmental components elicit tissue-specific functional phenotypes.
MEArrays can be printed using a wide variety of recombinant growth factors, cytokines, and purified ECM proteins, and combinations thereof. The platform is limited only by the availability of specific reagents. MEArrays are amenable to time-lapsed analysis, but most often are used for end point analyses of cellular functions that are measureable with fluorescent probes. For instance, DNA synthesis, apoptosis, acquisition of differentiated states, or production of specific gene products are commonly measured. Briefly, the basic flow of an MEArray experiment is to prepare slides coated with printing substrata and to prepare the master plate of proteins that are to be printed. Then the arrays are printed with a microarray robot, cells are allowed to attach, grow in culture, and then are chemically fixed upon reaching the experimental endpoint. Fluorescent or colorimetric assays, imaged with traditional microscopes or microarray scanners, are used to reveal relevant molecular and cellular phenotypes (Figure 1).

Fabrication and Use of MicroEnvironment microArrays MEArrays

A combinatorial functional screening method for gaining insights into the impacts of the molecular composition of microenvironments on cellular functions is described. The method takes advantage of existing microarray-based technologies to generate arrays of defined combinatorial microenvironments that support cell adhesion and functional analysis.

Herstellung und Verwendung von Mikroumgebung Microarrays (MEArrays)

The interactions between cells and their surrounding microenvironment have functional consequences for cellular behaviour. On the single cell level, ...