A novel FRET ‘off–on’ fluorescent probe for the selective detection of Fe 3+ , Al 3+ and Cr 3+ ions: Its ultrafast energy transfer kinetics and application in live cell imaging

A TBET based BODIPY-rhodamine dyad for the ratiometric detection of trivalent metal ions and its application in live cell imaging

“…These values indicated that 1 is capable to detect trivalent metal ions in nano-molar concentration ranges and the observed detection limits were lower compared to the most of the previously reported trivalent metal ion sensors (Table S1, Supporting data). Importantly, selection of rhodamine and BODIPY moieties as energy acceptor and donor, respectively in the probe 1 improved the metal ion linear response range compared to our previous rhodamine-naphthalimide probe [32]. Job's plot analysis was carried out to quantify the stoichiometry of 1 and trivalent metal ion complexes (Fig.…”

“…Even though several fluorescent probes are available for the detection of divalent or trivalent ions, probes useful for the collective detection of trivalent metal ions are very few in number. In the last couple of years, few reports based on 4 the chemosensors for trivalent metal ion detection are published in various international journals [29][30][31][32][33][34]. Most of these fluorescent probes operate based on metal ion induced fluorescence 'turn-on' or 'turn-off' mechanisms.…”

“…Hence, fluorescent probes that permit ratiometric detection of trivalent metal ions are noteworthy. To the best of our knowledge, only three probes are reported previously for the fluorescence ratiometric detection of trivalent metal ions [30][31][32] The reported probe (Py-TPE) is green fluorescent and turned to emit red fluorescence selectively in presence of trivalent metal ions. But it is highly pH sensitive and this extreme sensitivity to pH limits its applicability at different pH conditions and in biological samples.…”

“…Hence, fluorescent probes that permit ratiometric detection of trivalent metal ions over a broad range of pH and suitable to operate in biological samples are highly desirable. Recently, we have reported a rhodaminenaphthalimide dyad for the ratiometric detection of trivalent metal ions present in aqueous as well as biological samples [32]. This probe operates via fluorescence resonance energy transfer (FRET) mechanism.…”

“…This probe operates via fluorescence resonance energy transfer (FRET) mechanism. Since the emission bands of naphthalimide and rhodamine have considerable overlap, metal ion induced ratiometric fluorescence changes of the probe is less [32].…”