Ratiometric
fluorescent sensors based on ICT show promise in this regard as they
allow the measurement of emission intensities at two wavelengths,
which provides a built-in correction for environmental effects. Several
studies describing pyrene-containing chemosensors which selectively
and sensitively detect Cu2+, Zn2+ and other transition metals, inspired
us to design and synthesize a novel Cr3+ selective fluorescent
chemosensor [17–19].