CdTe QDs functionalized mesoporous silica nanoparticles loaded with conjugated polymers: A facile sensing platform for cupric (II) ion detection in water through FRET

This paper reported a facile method for fabricating CdTe quantum dots decorated fluorescent mesoporous silica nanoparticles containing poly(p-phenylenevinylene) by electrostatic interaction in aqueous solution. The resulted fluorescent hybrid nanomaterials showed the dual-emission centered at 500 nm and 717 nm, which can be used as a fluorescent probe to detect Cu ²⁺ in water through fluorescence resonance energy transfer. Cu ²⁺ can be captured by the amino groups of the polyethyleneimine to form an absorbent complex, resulting in a strong quenching of red-emission from CdTe quantum dots on the surface of nanoparticles via energy transfer. However, the green-emission of poly(p-phenylenevinylene) remained. Therefore the addition of Cu²⁺ induced the fluorescent evolution of the nanoprobe from red to green. The nanoprobe provided an efficient platform for the sensing of Cu²⁺ with a detection limit of 31.2 nM. Compared with pure quantum dots, the nanoprobe can distinguish Cu²⁺ from Hg²⁺.