Back to: Intracellular Amplifiers

npi SEC Series

PrintShare
High Speed Precision Time-Sharing Single Electrode Voltage/Current Clamp Amplifiers
npi SEC-10LX amplifiernpi SEC-10LX
Description

High Speed Precision Time-Sharing Single Electrode Voltage/Current Clamp Amplifiers

 

npi SEC-05LX

SEC-05LX

npi SEC-10LX

SEC-10LX

 

SEC series systems are versatile intracellular recording systems. SEC systems are the fastest and most accurate single-electrode current - and voltage - clamp systems available.
These amplifiers are suitable for recordings with high resistance microelectrodes, for tight-seal perforated patch, or whole-cell recording techniques. They also allow intracellular recordings during in vivo voltammetry experiments. Currently, SEC amplifiers are used in vertebrate (rat, mouse, cat, fish etc.) and invertebrate (leech, crab, snail, insect etc.) neurons, muscle cells, other excitable tissue and plant cells.
A significant improvement over other time-sharing amplifiers is that the SEC systems fully compensate the recording microelectrode.
This allows single electrode recordings with the same accuracy and speed of response as with the standard two electrode voltage clamp approach.
All systems include four (optionally six) modes of
operation, many automatic functions, protection circuits, versatile I/O signal conditioning units, and digitally controlled operation. All of these features make these amplifiers the ideal research instruments for all electrophysiological investigations using intracellular microelectrodes or suction electrodes (patch pipettes). SEC systems are also available as modules for the EPMS-07 system. The combination of two or more SEC modules results in a convenient instrument for recording in coupled cells.

 
     
  Specifications
 
 


MODES of OPERATION:

Re: Electrode Resistance Test; BR: Bride Mode (continuous); CC: Current Clamp mode; VC Voltage Clamp mode (discontinuous); Mode selector: rotary switch with four positions (SEC-05LX), or push buttons (SEC-10LX), LED indicators; remote selection by TTL inputs.

HEADSTAGES:
Standard headstage (SH) / Whole cell Headstages (SEC-HSP):
Operation voltage ±15 V; size: 100x40x25mm, headstage enclosure is connected to ground; electrode connector: gold plated SUBCLIC (SH); BNC connector (SEC-HSP), both with driven shield. Driven shield output:2.3 mm connector, range ±15 V, impedance 250
Ω, ground: 2.3 mm connector or headstage enclosure. Input resistance: >10E+13 Ω (internally trimmable). Current range (continuous mode): 150 nA into100 MΩ (SH); 15 nA into 100 MΩ (SEC-HSP), other calibrations are possible. CC control: Coarse control for input capacitance compensation. Holding bar (SH): diameter 8 mm, length 10 cm. Mounting plate (SEC-SHP headstage) 60x50 mm with four 6 mm holes.
Differential input headstage (SEC-HSD):
Electrode connectors: two SUBCLIC connectors with driven shield; Input resistance > 10E+13
Ω; CMR >90 db; other parameters same as SH headstage.
High voltage headstage (SEC 10H system):
Operating voltage range: ±150 V; size: 100x50x30 mm with heat sink 100x50x20, grounded enclosure; connectors same as SH headstage; CC control: trim potentiometer, 15 turns.
Electrode Parameter Controls:
Leakage current: adjustable to zero with ten-turn control; offset: ten-turn control, ±400 mV; capacity compensation; range 0-30 pF; coarse control on headstage, adapts compensation circuit to electrode parameters; fine control: ten-turn potentiometer.

BANDWIDTH and SPEED OF RESPONSE:
Full power bandwidth (Re=0): >100 kHz; rise time (10-90%, Re = 100 M
Ω)
ELECTRODE RESISTANCE TEST:
10 mV/M
Ω, obtained by application of square current pulses ±1 nA, display XXX MΩ.

CELL PENETRATION:
Overcompensation of capacity compensation, timer controlled, with remote switch connected via BNC connector (all systems). Application of DC pulses, variable frequency and amplitude, timer controlled, with remote switch connected via BNC connector (SEC-10 systems). Application of maximum continuous DC current, BUZZ, with toggle switch or remote switch connected via BNC connector (optional SEC-05 systems).

OSCILLATION SHUT-OFF:
Turns off current injection and capacity compensation, function indicated by red/green LED, disabled / off / reset switch, threshold set with linear control (0- 1200 mV).

SWITCHED MODES PARAMETERS:
Switching frequency: linear control, 1.5-50 kHz; display: XX.XX kHz. Duty cycles: 1/2, 1/4, 1/8, selected by toggle switch.

CURRENT RANGE vs. DUTY CYCLE:
1/8 - 15 nA; 1/4 - 30nA, 1/2 - 60 nA (standard 15V headstage)
1/8 - 1.5 nA; 1/4 - 3 nA, 1/2 - 6 nA (low noise headstage)
1/8 - 150 nA; 1/4 - 300 nA, 1/2 - 600 nA (high voltage headstage).

SWITCHED MODE OUTPUTS:
Electrode potential: max. ±15 V, output impedance 250
Ω.
Switching frequency: TTL (0.5 V), output impedance 250
Ω.

CURRENT OUTPUT:
Sensitivity: 0.1...10 V/nA in 1-2-5 steps, with lowpass Bessel filter, output impedance 250
Ω; sensitivity monitor: 1...7 V, 1V/switch position, output impedance 250 Ω; current display: X.XX nA.

POTENTIAL OUPUT:
Sensitivity x10 mV, with lowpass Bessel filter, output impedance 250
Ω; potential display: XXX mV.

AUDIO MONITOR: Pitch correlated with potential signal.

OUTPUT FILTERS:
SEC-05: two-pole (standard version) or four-pole lowpass bessel filters (SEC-05LX-BF) with 16 corner frequencies, 20 Hz - 20 kHz. Frequency monitor: -8..+7 V, 1 V/switch position, output impedance 250
Ω.
SEC-10: four-pole lowpass Bessel filters tunable in three ranges 0.3 - 20 kHz, output impedance 250
Ω.

CURRENT CLAMP:
Inputs: 1 nA/V, 0.1 nA/V with ON/OFF switches, input resistance >100 kΩ.
HOLD: X.XX nA ten-turn digital control with -/0/+ switch, max. 10 nA.
Gated input (SEC-10 systems only): X.XX nA with +/0/- switch, TTL input (HI >2.5 V, input resistance 10 k
Ω).
BRIDGE balance: XXX M
Ω with ten-turn digital control.
Noise (BRIDGE MODE): 400µV pp / pA pp with 100 M
Ω resistance ad 10 kHz bandwidth (internal four-pole Bessel filters).

VOLTAGE CLAMP:
Inputs: :10 mV/:40 mV, input resistance >100 k
Ω.
HOLD: XXX mV, ten-turn digital control with +/0/- switch, max. 1000 mV.
RISE TIME LIMIT: 0-2 ms.
GAIN: 100 nA/V - 10 µA/V ten-turn linear control.
Noise (filters set to 10 kHz, other settings see below).
Potential output: