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Properties of our
electrodes:
- Excellent
signal-to-noise ratio (SNR)
On
average, our electrodes provide extracellular spike amplitudes around a
few mV.
- Perfectly straight electrodes
Our
electrodes
are straight
(not curved or spiral) with enough rigidity to
penetrate brain tissue without suffering any deviation.
This guarantees
precise
stereotaxic positioning at deep brain structures.
- Suitable
for electrode arrays
The electrode
sharpness and the smooth glass insulation surface minimises
tissue dimpling.
- Ideal
mechanical and electrical properties
Pure
tungsten has the high stiffness
and excellent electrical properties.
The
borosilicate glass insulation gives a uniform insulation of a very high
resistivity and provides increased stiffness, especially at the tip.
- Good
replacement for glass micropipettes in extracellular recording
Metal-tip electrodes
are stronger than glass micropipettes and can isolate
extracellular single-unit activity for longer time periods and record
larger
amplitudes
(Wolbarsht
et al. 1960; Guld 1964).
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| Electrode
specification: |
|
Shank
diameter:
Overall
probe length:
Glass
insulated length:
Overall
probe diameter:
Taper:
Tip length (impedance):
Tip
conditioning:
Termination
option:
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125µm
tungsten wire (other diameters on
request)
45±1mm,
76±1mm,
100±1mm,
125±1mm
(other lengths on request)
overall
probe length minus 15mm (bare tungsten wire)
~200µm±15%
~5
deg
for dura removed, ~15 deg for dura piercing tip electrode
see
table below
unplated
no
connector
pin 220-P02 (0.032"/0.81mm)
pin Harting 09 67 000 8576 (0.040"/1.04mm)
socket 220-S02 (0.032"/0.81mm)
other
connectors on request
connectors
add extra ~8mm to probe length
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Tip length selection
guide:
Electrodes
with short tips,
up to ~20µm, are designed for single unit spike
recordings.
Electrodes
with longer tips, above
~20µm, are
intended for recordings of
multi-unit
activity (MUA) or local field potentials (LFP).
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Selection of standard electrodes for dura removed
experiments:
Tip length
[µm]
|
7.5
±1
|
10.0
±2.5
|
12.5
±2.5
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15.0
±3
|
17.5
±3
|
20
±3
|
25
±3
|
30
±5
|
35
±5
|
40
±5
|
45
±5
|
50
±5
|
longer
on
request
|
Impedance
[MOhm]
mean ±1std
|
5.5
±1.6
|
4.2
±1.3
|
3.3
±1.0
|
2.6
±0.8
|
2.2
±0.6
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1.8
±0.5
|
1.3
±0.4
|
1.0
±0.3
|
0.8
±0.2
|
0.7
±0.2
|
0.6
±0.1
|
0.5
±0.1
|
|
Electrode impedances
measured in 0.9% saline with 10nA current at
1kHz.
|
Due
to the very fine and delicate nature of the microelectrode tip for dura
removed experiments, it is strongly advisable to handle them with great
care.
Selection
of electrodes with strengthen tips for dura piercing experiments:
The same as for dura removed experiments, however the electrodes for
dura piercing experiments have approximately 30%
lower impedances due to increased surface of wider tapered electrode
tip compared to electrodes for dura removed experiments (see electrode
construction).
Selection
of electrodes with extra fine tips for very small cells and large fibers:
The same as for dura removed experiments, however the electrodes with
extra fine tips have approximately 30%
higher impedances due to decreased surface of narrower tapered
electrode
tip compared to electrodes for dura removed experiments (see electrode
construction).
| Electrode
construction: |
|
If
you are unsure which tip length would
work best for your experiments,
we would be pleased to discuss your requirements.
We can also prepare a selection of different electrode tip lengths in
your first box at no extra cost.
Every
electrode is inspected for highest quality assurance.
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Flexible silicone insulated electrode extension cables:
- extension
cable with
socket 220-S02 matching pin 220-P02,
- extension cable with socket Harting 09 67
000 8476
matching pin Harting 09 67 000 8576.
Extension cables are available:
- in four colours (black, red, blue and
yellow;
other colours on request),
- in four lengths (40cm, 60cm, 80cm, 100cm;
other lengths on request) and
- with 3 conductor sizes (22AWG and outer
diameter 1.8mm, 24AWG OD 1.7mm, 26AWG OD 1.5mm).
All
cables are £9 each. |
|
Straight cut lengths of tungsten wire:
- diameter
0.127mm ±1% (0.005") , purity 99.95%+, temperature annealed,
electropolished, condition clean, max bow <0.001''.
- made from the highest quality Japan tungsten
wire.
length
[mm±1mm]
|
38
(1.5")
|
45 |
60
|
76
(3") |
90
|
100
(4")
|
110
|
125
(5")
|
150
(6")
|
quantity [pcs] /
price [GBP]
|
50 / £30
100 / £50
500 / £250
1000 / £400
|
50 / £30
100 / £50
500 / £250
1000 / £400 |
50 / £40
100 / £60
500 / £300
1000 / £500 |
50 / £40
100 / £60
500 / £300
1000 / £500 |
50 / £60
100 / £100
500 / £400
1000 / £700 |
50 / £60
100 / £100
500 / £400
1000 / £700 |
50 / £80
100 / £120
500 / £500
1000 / £850 |
50 / £80
100 / £120
500 / £500
1000 / £850 |
50 / £100
100 / £140
500 / £600
1000 / £1100 |
Typical lengths 1.5",
3", 4", 5", 6" are available for next day delivery, other lenghs
are
manufactured on
request with maximum lead
time of 1 week.
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Other
diameters (0.1mm/0.004'', 0.15mm/0.006'', 0.2mm/0.008'',
0.25mm/0.01'', 0.50mm/0.02'') of straight cut
lengths of tungsten
wire are manufactured on request.
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