Fluorescent ion indicators and ionophores
Monitoring intracellular ion change is vital to the understanding of signaling and functional pathways in cellular systems. Ion changes are central to many fundamental processes such as muscle contraction as well as synaptic nerve signal transmission. Homeostatic regulation of these ionic gradients is critical for most cellular functions. Therefore measuring ionic concentrations with both spatial and temporal resolution has become critical in research ranging from drug discovery to neuronal function studies.
We provide a wide range of ion indicators and ionophores to track calcium and other ion concentrations with intense fluorescent signals over a range of different wavelengths.
Calcium indicators and ionophores
Calcium (Ca2+) is an important ubiquitous second messenger, involved in the regulation of a diverse range of cellular processes, including cell proliferation, gene transcription, muscle contraction, and endocytosis.
Browse our reagents and find the optimal Ca2+ indicator, chelators, and ionophores for your experiments.
Product highlights
Calmycin
- Has intrinsic fluorescence excitable by UV light
- Less useful with UV-excitable Ca2+ indicators like Fura-2 but useful for long-wavelength Ca2+ indicators like Fluo-2 (see below)
Ionomycin
- Effective Ca2+ ionophore
- Commonly used to calibrate fluorescent Ca2+ regulators and to modify intracellular Ca2+ concentrations
Sodium and potassium indicators and ionophores
There is a major difference in the sodium ion concentration inside and outside the cell (5-40 mM intracellular; 120-450 mM extracellular, depending on the organism). This concentration gradient is essential for nutrient uptake, to regulate concentrations of other intracellular ions and solutes, and to generate and transmit electrical impulses in excitable cells. The low intracellular sodium concentration requires the use of sensitive dyes able to register any small variation. Since intracellular potassium concentration is typically higher than sodium (in excess of 100 mM), Na+ indicators should respond selectively to Na+, not K+.
Ionophores facilitate the transport of Na+ ions through lipid membranes, with the net effect of allowing Na+ to flow from a compartment with higher Na+ concentration, through the membrane, into a compartment with lower Na+ concentrations. These ionophores can be used to equilibrate intracellular and extracellular Na+ concentrations.
Product highlights
Momensin sodium salt
- Na+ ionophore
- Forms lipophilic complexes with monovalent cations to induce Na+ influx and H+/K+ efflux
- Induces apoptosis
Nigericin
- Selective for K+ and H+
- Commonly used in the fluorescence calibration of cytosolic pH indicators
Valinomycin
- Natural, lipid-soluble molecule that binds potassium ions and facilitates their transfer across lipid bilayers
- Has a 10,000-fold selectivity for K+ over Na+
pH and membrane potential indicators
Changes in cytosolic intracellular pH (pHi) and membrane potential play a central role in many physiological processes, including nerve-impulse propagation, muscle contraction, and cell signaling.
We offer a range of highly cited and novel indicators enabling you to track pH and membrane potential in different cell types.
Product highlights
BCECF
- The most popular indicator for studying Phi
- pKa of 6.98
- Excitation spectrum maximum 507 nm, isoexcitation point at 438 nm
- Intracellular pH can be estimated by measuring the ratio of fluorescence intensities at 500 and 450 nm
FFN102 (mini 102)
- Novel, pH-responsive fluorescent false neurotransmitter
- Rodent DAT and VMAT2 substrate
- Exhibits greater fluorescence emission in neutral than acidic environments
- Sufficiently bright, photostable, and suitable for two-photon fluorescence microscopy and standard fluorescent microscopy
FFN202 (mini 202)
- Novel, pH-responsive fluorescent false neurotransmitter
- Rodent DAT and VMAT2 substrate
- Enables in situ pH measurement of secretory catecholamine vesicles in PC-12 cells
- Sufficiently bright, photostable and suitable for two-photon fluorescence microscopy and standard fluorescent microscopy
- Compatible with GFP tags
JC-1
- Widely used for determining in mitochondrial membrane potential flow cytometry and fluorescent microscopy
- Exhibits potential-dependent accumulation in mitochondria
- Reversibly changes color as membrane potentials increase
- Can be used to indicate the initiation of apoptosis
