Selective chemosensing of spermidine based on fluorescent organic nanoparticles in aqueous media via a Fe3+ displacement assay

A novel fluorescent chemosensor based on fluorescent organic nanoparticles (F1) has been synthesized. This tripodal framework shows significant fluorescence quenching for Fe3+ ions from among nineteen metal ions due to the formation of a F-1.Fe3+ complex. The lowest detectable concentration of F1 for Fe3+ ions was found to be 1.66 mM. Upon the addition of spermidine (a biologically active amine), the fluorescence intensity of the aqueous solution of complex increases with a detection limit of 3.68 mM indicating that spermidine can displace Fe3+ ions from the F-1.Fe3+ complex. Moreover, the recognition of spermidine was selective with no interference from other biogenic amines studied. Thus, F-1.Fe3+ acts as a potential sensor for spermidine through a cation displacement assay in aqueous media.