Highly selective fluorescent chemosensor for detection of Fe3+ based on Fe3O4@ZnO

The combination of fluorescent nanoparticles and specific molecular probes appears to be a promising strategy for developing fluorescent nanoprobes. In this work, L-cysteine (L-Cys) capped Fe 3 O 4 @ZnO core-shell nanoparticles were synthesized for the highly selective detection of Fe 3+ . The proposed nanoprobe shows excellent fluorescent property and high selectivity for Fe 3+ due to the binding affinity of L-Cys with Fe 3+ . The binding of Fe 3+ to the nanoprobe induces an apparent decrease of the fluorescence. Thus a highly selective fluorescent chemosensor for Fe 3+ was proposed based on Fe 3 O 4 @ZnO nanoprobe. The magnetism of the nanoprobe enables the facile separation of bound Fe 3+ from the sample solution with an external magnetic field, which effectively reduces the interference of matrix. The detection limit was 3 nmol L −1 with a rapid response time of less than 1 min. The proposed method was applied to detect Fe 3+ in both serum and wastewater samples with acceptable performance. All above features indicated that the proposed fluorescent probe as sensing platform held great potential in applications of biological and analytical field.