Calcein Blue, a membrane-impermeant fluorescent dye, is a coumarin derivative that contains an iminodiacetic acid structure. Calcein Blue is also a metallofluorochromic indicator^[1][2][3].

The fluorescence of Calcein Blue (CB) is quenched by the Fe²⁺ ion in the Calcein Blue-Fe²⁺ complex. When dopamine is added to a solution of the Calcein Blue-Fe²⁺ complex, a dopamine-Fe²⁺ complex is formed as the result of a ligand exchange reaction between Calcein Blue and dopamine which permits the fluorescence from Calcein Blue to be recovered. The fluorescence intensity at the wavelength of 440 nm (at the excitation wavelength of 340 nm) is found to be proportional to the concentration of the dopamine added to the Calcein Blue-Fe²⁺ complex solution, which permits dopamine to be quantitatively determined. The Calcein Blue-Fe²⁺ complex shows a high selectivity for dopamine among the catecholamines and related compounds examined^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

* Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.
Storage method and period of stock solution: -80°C, 6 months; -20°C, 1 month (protect from light). When stored at -80°C, please use it within 6 months. When stored at -20°C, please use it within 1 month.

• [1]. Seto D, et al. A simple and selective fluorometric assay for dopamine using a calcein blue-Fe2+ complex fluorophore. Talanta. 2012 May 30;94:36-43.  [Content Brief]

  [2]. Sankaranarayanan R, et al. A new fluorimetric method for the detection and quantification of siderophores using Calcein Blue, with potential as a bacterial detection tool. Appl Microbiol Biotechnol. 2015 Mar;99(5):2339-49.  [Content Brief]

  [3]. G M Huitink, et al. Methyl calcein blue and other analogues of calcein blue. Talanta. 1974 Nov;21(11):1193-202.  [Content Brief]