Merck, 1.09278, Wright′s eosine methylene blue

General description
Wright′s eosin methylene blue - for microscopy staining dye, is a defined mixture of the dyes C.I. 52015 and C.I. 45380 for hematological staining procedures and is used in conjunction with eosin Y. The Wright′s eosin methylene blue solution can be used for analysis and diagnostics in the whole blood differentiation. The staining of the nuclei is due of the molecular interaction of the Eosin Y dye and a complex of Azur B with DNA. Both dyes assemble to an Eosin Y - Azur B-DNA complex and the intensity of the resulting stain depends on the content of Azur B and the ratio of Azur B : Eosin Y. Furthermore, the resulting stain can vary depending on the influence of fixation, staining times, pH-value of the solutions or buffer substances. For more details, please see instructions for use (IFU). This product is registered as IVD and CE marked. For more details, please see instructions for use (IFU). The IFU can be downloaded from this webpage.
Analysis Note
Identity (UV/VIS-Spectrum): passes test
pH-value (0,01 %; methanol 50 %): 6.0 - 7.0
Absorption maximum λ 1 (Methanol): 648 - 651 nm
Absorption maximum λ 2 (Methanol): 521 - 524 nm
Spec. Absorptivity A 1%/1cm
- λ1max; 0.0005 %; methanol; calculated on dried substance:
1200 - 1400
- λ2max; 0.0005 %; methanol; calculated on dried substance: 650 - 850
TLC-Test: passes test
Loss on drying (105 °C): ≤ 10 %
Suitability for microscopy: passes test