APG-4 – ION Biosciences https://ionbiosciences.com Fluorescent Ion Indicators | Assay Kits Fri, 24 Apr 2026 17:37:40 +0000 en-US hourly 1 https://wordpress.org/?v=7.1.4 https://ionbiosciences.com/wp-content/uploads/ION-Bio-100x100.png APG-4 – ION Biosciences https://ionbiosciences.com 32 32 IPG-4 AM https://ionbiosciences.com/store/ipg-4-am/ Wed, 28 Jun 2023 19:27:01 +0000 https://ionbiosciences.com/product/ipg-4-am-2/

ION Potassium Green – 4 (IPG-4) is a yellow-green fluorescent, potassium (K⁺) indicator with Ex/Em: 525 nm/545 nm and a high-selectivity for potassium over other monovalent cations. IPG-4 has the highest affinity (Kd = 7 mM) among IPG analogues – IPG-2 (Kd = 18 mM) and IPG-1 (Kd = 50 mM), and is useful for measuring changes in intracellular or extracellular potassium concentrations.

IPG-4, a potassium indicator, fluorescence spectra
GIRK channel (Kir3.1/3.2) activator dose response curve comparison with data acquired using IPG-4 AM on a plate reader and microscope. Inset shows a dose response curve generated using thallium flux.
Fluorescence data of IPG-4 potassium indicator response to potassium.
Image analysis of IPG-4 assay used to identify activators of a GIRK potassium channel.
Fluorescence profiles and images of cells loaded with IPG-4 in the presence or absence of probenecid demonstrating IPG-4 is not a Pgp substrate, and can be used to conduct probenecid-free potassium channel assays.
IPG-4_Monovalent_Divalent
]]> IPG-4 TMA⁺ Salt https://ionbiosciences.com/store/ipg-4-tma-salt/ Wed, 28 Jun 2023 19:26:41 +0000 https://ionbiosciences.com/?post_type=product&p=26615

ION Potassium Green – 4 (IPG-4) is a yellow-green fluorescent, intracellular potassium (K⁺) indicator with Ex/Em: 525 nm/545 nm and a high-sensitivity to detect small changes in K⁺ concentration. IPG-4 has the highest affinity (Kd = 7 mM) among IPG analogues – IPG-2 (Kd = 18 mM) and IPG-1 (Kd = 50 mM).

IPG-4 TMA⁺ salt is a membrane impermeable form of IPG-4 that can be used in lipid membrane-free systems, in liposomes, or can be introduced into cells by electroporation, microinjection or other methods. IPG-4 has been successfully used as a sensor for extracellular K⁺.

IPG-4 (ion potassium green - 4) salt, a fluorescent potassium indicator ideal for extracellular applications.
IPG-4_Monovalent_Divalent
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