for fluorescence, ≥93% (HPLC)

Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
MDL number:
PubChem Substance ID:

Quality Level


for fluorescence


≥93% (HPLC)


λex 524 nm; λem 545 nm (after derivatization with 2-mercaptoethanol)

storage temp.


SMILES string




InChI key


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5-Maleimido-eosin (eosin-5-maleimide, EMA) binding is widely used in a flow cytometry to detect hereditary spherocytosis (HS).

Other Notes

Triplet probe. Measurement of rotational diffusion of protein in solution and in membranes, including myosin and pyruvate dehydrogenase

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


NONH for all modes of transport

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis
Certificate of Origin
A J Visser et al.
European journal of biochemistry, 121(1), 233-235 (1981-12-01)
The enzymatically reduced lipoyl residues of the transacetylase component of the pyruvate dehydrogenase complex from Escherichia coli were labeled with eosin maleimide. Using eosin as triplet probe, triplet-triplet absorption dichroism measurements were performed to obtain rotational correlation times of the...
Delay in the measurement of eosin-5'-maleimide (EMA) binding does not affect the test result for the diagnosis of hereditary spherocytosis.
Ciepiela O, Kotula I, Gorska E, et al.
Clinical Chemistry and Laboratory Medicine, 0, 1-7 (2012)
Paola Bianchi et al.
Haematologica, 97(4), 516-523 (2011-11-08)
The laboratory diagnosis of hereditary spherocytosis commonly relies on NaCl-based or glycerol-based red cell osmotic fragility tests; more recently, an assay directly targeting the hereditary spherocytosis molecular defect (eosin-5'-maleimide-binding test) has been proposed. None of the available tests identifies all...
S Ishiwata et al.
The Journal of biological chemistry, 262(17), 8314-8317 (1987-06-15)
We studied the rotational Brownian motions of myosin heads, of which the sulfhydryl group was selectively labeled with the triplet probe 5-eosinylmaleimide, in myofibril by using flash-induced phosphorescence anisotropy decay measurements. The anisotropy decay curve under relaxing conditions consisted of...
Renée L Crisp et al.
Pediatric blood & cancer, 59(7), 1299-1301 (2012-04-11)
We studied 31 children with hemolytic anemia, or with positive family history for hereditary spherocytosis (HS), to assess the reliability of capillary blood samples for the diagnosis. HS was diagnosed in 20 patients. Cryohemolysis (CH) was positive in 94% and...

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