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Mag-Fluo-4, Tetrapotassium Salt

Membrane-impermeant form of Mag-Fluo-4, a fluorescent magnesium and calcium ion indicator that is an analog of Fluo-4.

Product Attributes


Calcium indicators

Cell permeability

Membrane impermeant

Indicator type



493/517 nm (high Mg2+)

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Catalog #
500 ug
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Product Description

Mag-Fluo-4 is a fluorescent ion indicator and is an analog of Fluo-4. The indicator has an affinity for magnesium (Kd = 4.7 mM) and low-affinity for calcium (Kd = 22 uM) with absorbance/emission at 493/517 nm (high Mg2+). The cell membrane-impermeant tetrapotassium salt form can be introduced into cells by microinjection.

  • λExEm (high Mg2+): 493/517 nm
  • Orange solid soluble in water
  • Store 4°C and protect from light
  • C25H13F2K4NO10
  • MW: 682


1. Biophys J. (2009) Oct 7; 97(7):1864 doi: 10.1016/j.bpj.2009.07.021
2. Biochem J. (2002) Oct 1; 367(Pt1):137 doi: 10.1042/BJ20020305
3. Biochima et Biophys Acta - Mol Cell Res. (2017) June; 1864(6):977
4. Biochem & Biophys Res Comm. (2014) November 28; 454(4):572


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