VABSC-1 Dye (Voltage Assay Background Suppression Compound)

Description

Voltage Sensor Probes (VSPs) are a Fluorescence Resonance Energy Transfer (FRET)-based voltage-sensing assay technology used to measure changes in cellular membrane electrical potential. VSPs are ideal for screening compounds that modulate ion channels because they provide:

• High-throughput capabilities-screen 32,000 samples in one day
• Highly sensitive detection-accurately and precisely report a 1% change in the Emission Ratio per mV
• Rapid detection response-sub-second time response
• Ratiometric readout (the Emission Ratio)-reduces experimental errors arising from well-to-well variations in
• cell number, addition artifacts, dye loading, plate inconsistencies, temperature fluctuations, and signal intensities. Allows for highly accurate, real-time optical readout of changes in membrane potential
• Universal methodology-applicable to any target that changes the membrane potential
• Highly accurate, real-time optical readout-results correlate with patch clamp data

How VSPs Work
VSPs use a FRET pair composed of one of two highly fluorescent, mobile, voltage-sensitive acceptor oxonols [DiSBAC²(3) or DiSBAC⁴(3)] and a fluorescent, membrane-bound coumarinphospholipid FRET donor (CC2-DMPE). When the cell interior has a relatively negative potential, the oxonol dye will bind to the exterior of the cell membrane, resulting in efficient FRET. When the cell interior has a relatively positive potential, however,
the oxonol dye will bind to the interior of the cell membrane, thus separating the FRET pair and disrupting FRET.

DiSBAC²(3) is used for most ion channel screening applications because it is more sensitive, easier to load, more stable than DiSBAC⁴(3), and can remain in the extracellular media. The time response of this oxonol is ~500 ms. DiSBAC⁴(3) requires a surfactant for cellular loading and a washing step to remove excess dye, but responds to changes to the membrane potential in ~20 ms. This dye is useful for applications that require faster response time or no added dye in the extracellular solution.

VABSC-1 Dye (Voltage Assay Background Suppression Compound) performs in conjunction with CC2-DMPE to suppress background signal, providing optimal performance and minimal toxicity.

Figures

Specifications

Indicator Properties:	Fluorescent Dye-Based
Indicator Type:	Voltage Sensor Probes
Product Size:	1 g
Shipping Condition:	Room Temperature

Contents & storage