A thin-layer chromatography plate prepared from BODIPY-based receptor immobilized SiO 2 nanoparticles as a portable chemosensor for Pb 2+

A new fluorescence receptor based on BODIPY-immobilized silica nanoparticles (BODIPY-SiO(2)) exhibits a high affinity and selectivity for Pb(2+) over competing metal ions in water. An overall emission change of ca. 100-fold at the emission maximum was observed for Pb(2+). The fluorescence receptor BODIPY-SiO(2) can remove 97% and 95% of the initial 100 ppb Pb(2+) from human blood and waste solution, respectively. Experiments show the fluorescence receptor BODIPY-SiO(2) can be a potentially useful and effective agent for the selective separation and rapid removal of Pb(2+)in vivo. We also prepared a portable chemosensor kit by coating a 4 μm thick film of BODIPY-SiO(2) onto a glass substrate. We found that this BODIPY-SiO(2) film detects Pb(2+) ions at pH 7.4 with a sensitivity of 3.2 nM. Finally, we tested the effect of pH on BODIPY-SiO(2) with Pb(2+) ions between pH 3.0 and 11.0. The fluorescence changes of BODIPY-SiO(2) were almost constant between pH 3 and 11. The results imply that the BODIPY-SiO(2) film is applicable as a portable chemosensor for detection of Pb(2+) ions in the environmental field.