Br-BODIPY

Br-BODIPY 493/503 8-Bromomethyl-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-3-indacene MW 341... 

The excitation maximum for Br-BODIPY 493/503 is 515nm and its emission occurs at 525 nm when dissolved in methanol. Upon coupling to a sulfhydryl compound, however, the excitation wavelength of the adduct decreases to 493 nm and its emission drops to 503 nm. The very small lOnm Stoke s shift may be a problem, particularly in avoiding interference due to of excitation-light scattering in critical emission measurements. Sub-optimal excitation wavelengths... 

Figure 9.36 Br-BODIPY can be used to modify sulfhydryl-containing molecules to form thioether linkages.

Br-BODIPY 493/503 is insoluble in aqueous reaction mixtures, but may be dissolved in DMF or DMSO as a concentrated stock solution prior to addition of a small amount to a buffered solution. Coupling to sulfhydryl-containing molecules is rapid, leading to the formation of a thioether linkage. The reaction may be done in 50mM sodium borate, 5mM EDTA, pH 8.3. An important consideration is to protect the iodoacetyl derivative from light which may generate iodine and reduce the reactivity of the probe. 

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