VA-10

Voltammetry / Amperometry

Description

The VA-10X is a sensitive (picoampere range) current amplifier that is intended for voltammetric measurements with carbon-fiber microelectrodes in biological systems, where the total currents do not exceed a few tens of nA.
It was designed at the Max-Planck-Institute for Experimental Medicine in Göttingen as an economically priced alternative to do-it-yourself systems and expensive commercial systems.

There is also a modular version of the VA-10 available.

Details

The VA-10X is a sensitive (picoampere range) current amplifier that is intended for voltammetric measurements with carbon-fiber microelectrodes in biological systems, where the total currents do not exceed a few tens of nA.
It was designed at the Max-Planck-Institute for Experimental Medicine in Göttingen as an economically priced alternative to do-it-yourself systems and expensive commercial systems.
It can be used for either DC amperometry using the built-in voltage source, or it can be operated with user-supplied external voltage waveforms (e.g. for cyclic voltammetry).
The VA-10X is ideally suited for measurements from single cells plated onto glass cover slips and with carbon-fiber disk electrodes having diameters of 10 µM or less. npi recommends ALA CFE-2 carbon fiber electrodes. However, it can also be used for measurements made on superficially located cells in tissue slices.
The standard VA-10X is not recommended for use in in-vivo recordings with carbon-fiber electrodes having long cylindrical measuring surfaces, because in this case currents approach the µA range. Ask npi electronic for headstages with different feedback resistors.
Optionally, the VA-10X can be equipped with a frequency booster in order to enhance the bandwidth to several kHz.

The VA-10 is also available as module for the EPMS-07 system.

Features

Features:

  • Optional frequency booster for recording very fast signals
  • Filter settings from 20 Hz to 20 kHz in sixteen steps, 4-pole or 8-pole Bessel filter (1-pole filter on request)
  • 3-electrode headstage for a floating command potential available
  • Gain settings from 0.5 to 50 mV / pA in seven steps
  • Precise built-in voltage source for DC amperometry (+/- 1000 mV standard, +/- 2000 mV optional)
  • Low noise, works in picoampere range
  • Ideally suited for recordings from single cells
  • Can be operated with external waveforms for cyclic voltammetry
  • Telegraph outputs for easy interfacing to data acquisition systems
  • Applications:
    • Allows simultaneous electrophysiological recordings during voltammetric or amperometric investigations using headstages with differential inputs
    • Can be used in scaning electrochemical microscopy
    • Also suitable for lipid bilayer recordings

Use with 5 µm carbon fiber electrodes (ALA-CFE-2)

Also available as module for the EPMS-07 system.

Technical Data

HEADSTAGE: 
Input voltage range: ±1200 mV
Operating voltage: ±12 V
Enclosure: Size: 40 x 70 x 20 mm, driven shield (COMMAND potential)
Mounting plate: 50 x 70 mm, not conducting
Electrode connector:driven shield (COMMAND potential)
Ground connector: 1 mm connector (black)
Driven shield output: 1 mm connector (red)
Input resistance: >1013 Ω
Current range: ±20 nA
Feedback resistor: 500 MΩ

OUTPUTS: 
Impedance: 250 Ω
FILTERED: BNC connector, sensitivity selectable with GAIN switch, FILTERED with LP Bessel FILTER
UNFILTERED: BNC connector, sensitivity selectable with GAIN switch

INPUTS: 

Resistance: 1 MΩ

VOLTAGE SOURCE: 
COMMAND VOLTAGE set by 10-turn potentiometer, range: (1000 mV, polarity selectable with polarity switch (+, 0, -), display XXXX mV
COMMAND VOLTAGE:
INPUT BNC connector, sensitivity: /10, also displayed

LP FILTER: 
4-pole or 8-pole Bessel FILTER
16 corner frequencies: 20, 50, 100, 200, 300 500, 700, 1k, 1.3k, 2k, 3k, 5k, 8k, 10k, 13k, 20k Hz.

NOISE: 
<1 pA

GAIN: 
7-position rotary switch (x0.5, x1, x2.5, x5, x10, x25, x50 mV / pA)

POWER REQUIREMENTS: 
115/230 V AC, 60/50 Hz, fuse 0.4/0.2 A, slow.

DIMENSIONS:
19″ rackmount cabinet, 19″ (483 mm), 10″ (250 mm), 3.5″ (88 mm)

Ordering

Part no. Description
VA-10-X4 Amplifier for voltammetry and amperometry with 4-pole BESSEL filter
VA-10X-8 Amplifier for voltammetry and amperometry with 8-pole BESSEL filter
VA-10-FB Frequency Booster for enhancement of the bandwidth
VA-HS3 Differential (3-Electrode) headstage for VA-10 amplifier
VA-CFE Carbon Fiber electrodes, 5 µm diameter, using the Anodic Electrophoretic Deposition of Paint (EDP) method
VA-CFE-H-BNC CFE holder for headstages with BNC connector
VA-CFE-H-AXU CFE holder for AXON amplifier

Downloads

Manuals:
VA-10X manual

Brochure:
VA-10X Brochure

References:
VA-10X Reference List