Carbon dots and quantum dots-based nanohybrid as a ratiometric fluorescent probe for Fe3+ and phytic acid sensing

The selective recognition of metal ions is very important and the development of novel chemosensor is still a challenge. Herein, a single dual-emissive fluorescence probe was developed to detect Fe3+ and phytic acid (PA). Red quantum dots (CdSe) were embedded into silica nanoparticles for an internal standard emission, whereas blue carbon dots (CDs) were covalently linked onto the surface of silica as a sensing element to achieve a more precise and sensitive detection. The fluorescence of the CDs was effectively quenched by Fe3+ via a photoinduced electron transfer (PET) process. Fe3+ could selectively bind to phytic acid, thus leading to the recovered fluorescence of the CDs in the presence of Fe3+. Upon addition of PA to the CdSe@SiO2-CDs/Fe(III) complex dispersion, the fluorescence of the CDs significantly increased. The ratiometric probe enabled the selective detection of PA within 0.08-1.6 mM and a limit of detection of 1.5 μM. Overall, this method provided high selectivity, stability, and recovery ratio in the detection of Fe3+ and PA. Copyright © 2018, AIDIC Servizi S.r.l.