A luminescent boron difluoride derivative of the YELLOW 101 dye.

Inspired on the outstanding behavior of the BODIPY dye, a new fluorescent boron fluoride derivative of the classical 2,2'-dihydroxy-1,1'-naphtalazine or YELLOW 101 dye has been synthesized and investigated in this work. Analogously to YELLOW 101 (λ = 510 nm), the new species, here denoted BYELLOW 101, exhibits strong fluorescence around 570 and 535 nm in the solid form and in organic solvents, respectively. The observed red shift of the luminescence emission can be explored in the superparamagnetic fluorescent materials employed in MPI (magnetic particle inspection) technology, decreasing the influence of the FRET mechanism, - a critical limitation in this type of system. BYELLOW 101 is stable in solid form, but in organic solvents, it hydrolyses very slowly regenerating the initial dye, keeping the fluorescence emission but exhibiting a small blue shift along the time.