Orbit mini® Getting Started

The Orbit mini
The Orbit mini is explicitly designed to meet thespecial requirements of experiments on artificial
bilayers. Use of Ionera’s MECA (micro electrodecavity array) chip technology combined with stateof the art low noise amplifiers (Elements S.R.L.)
enables the fully parallel recording of four separate
lipid bilayers at bandwidths up to 100 kHz withexcellent signal-to-noise ratios. The system has beenvalidated with targets as diverse as ligand andvoltage gated ion channels, porins and origami
DNA constructs, antimicrobial peptides ormembrane active toxins. The optional temperature
control for the Orbit mini furthermore allows forexperiments on temperature sensitive species suchas TRP channels or for experiments at physiologicaltemperatures.

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Material

2

Start the software and connect the device

3

Calibrate the Orbit mini

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Orbit mini connected to a computer via USB
Element’s EDR 3 software installed on the computer
Nanion Orbit mini test cell
MECA 4 recording chip, buffer of choice
Lipid stock solution (e.g. DPhPC, c = 10 mg/ml in octane)
Instrumentation for painting bilayers (pipette, brush, Teflon piece…)

Connect the Orbit mini to a computer via a mini-USB to USB cable, startthe EDR 3 software and connect the device by pressing the ‘connect’button.

The Orbit mini needs to be calibrated after each startup of the software
Choose the 200 pA gain and insert the test cell
Close both lids and activate the ‘digital compensation’ by ticking thebox under Settings → Controls
The software will automatically adjust the four signals close to zero; untick
the box again afterwards
Use the ‘Voffset correction’ to manually finetune each channel to zero
Untick the ‘digital compensation’ box and remove the testcell
The Orbit mini is now calibrated. To avoid miscalibration, please:

DO NOT RUN THE DIGITAL COMPENSATION WITHOUT TESTCELL!

QSG_06002_005

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Apply MECA 4 chip and fill the cavities
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5Place a MECA 4 chip in the Orbit mini and close the lower lid
apply 150 µl buffer of choice on the MECA 4 chip with a pipette
Follow the wetting of the cavities e.g. by application of a triangularvoltage wave (Protocol 1)
The resulting signal should alternate between the positive and negative
maximum of the chosen gain range (depicted on the right) as thecavities are uncovered and thus enable unhindered ion flux
If the cavities are not readily wetted, please use the provided wetting
tool to gently push the buffer inside the cavities

Paint lipid bilayers
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Manually paint a lipid bilayer on the chip’s four cavities by gently
spreading lipid solution over them with e.g. one of the provided tools forpainting (brush, Teflon piece in holder, glass rod)
Nanion recommends to paint bilayers via lipid covered air bubbles:
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6

Take e.g. a 10 μl Eppendorf pipette (small white tip)
Cover the tip with lipids by dipping it into the lipid stock solution without aspirating any of it.
Due to capillary forces a small amount of lipid solution will remain in the pipette tip - squeeze
out any of these residues from the pipette tip
Place the tip on the chip’s surface close to a cavity, dispense a small air bubble (2-3 µl) overthe cavity and aspirate it back. This results in the formation of a lipid bilayer which can bemonitored by following the change in the current response: the signal should not go into
saturation anymore and exhibit capacitive properties as shown on the right

Repeat step 3 on all cavities. If bilayer formation is not successful within afirst run start again at step 1.
Note: Do not throw the tip away afterwards. It can be still used to repaintbroken bilayers during the experiment.
For a short video about this protocol please visit www.nanion.deJudge bilayer qualityUse the ZAP function (Settings → Voltage Protocols) to judge the status ofthe bilayers: a thinned out lipid monolayer should get destroyed
Simply repaint the bilayers afterwards
Use the RC estimation function (Analysis) to calculate the membrane
capacitance Cm via an applied test-pulse
Cm will vary for different lipid mixtures and/or solvents but thecapacitance for freshly painted bilayers can easily be compared to theone found for functional bilayers

7

Clean MECA 4 chips

8Optimize your system

Clean the MECA 4 chips directly after each experiment
Use double-distilled water to remove buffer residues
Use ethanol and/or isopropanol to remove lipid residues
The chips are quite robust: use precision wipes to manually clean themThoroughly dry the MECA chips before starting a new experiment as you
otherwise might encounter offsets in the empty chip signals

Switch off channels with broken membranes (Settings → Controls) as
open cavities might give rise to offsets in the remaining channels
Make sure that you always get zappable, thinned out membranesoIf this fails, try different lipid-to-solvent ratios in the range of 1mg
to 30 mg lipid(s) per ml solvento
Try different solvents like octane, decane, nonane or evenhexane until you find the one best suited for your system
The Orbit mini itself as well as the EDR software and a list of application
examples are being constantly updated to provide further options andto increase the ease of use - so make sure to regularly checkowww.nanion.deowww.elements-ic.com
owww.ionera.de
for the newest updates and documentation!

Nanion Technologies GmbH | Munich | Germany | www.nanion.de