Fluorescence Probe for Detection of Paeoniflorin Using ZnTe Quantum Dots

A novel fluorescence probe based on ZnTe quantum dots (QDs) modified by 3-Mercaptopropionic acid had been constructed for the selective and sensitive detection of paeoniflorin. ZnTe QDs were successfully synthesized via a simple method in aqueous solutions. The average size of ZnTe QDs was 12 nm and characterized by transmission electron microscopy and X-ray diffractograms. Upon addition of paeoniflorin into the system, the fluorescence intensity was significantly quenched in buffer solution. This proposed fluorescence sensor can be used to detect paeoniflorin under certain conditions, which pH was 7.5, temperature was 25 °C and incubation time was 20 min. Additionally, the quenching procedure was presumed to be static and the mechanism was proved by the rate constant $K_{q}\,(9.70 \times 10^{11}\text {L}\cdot \text {mol}^{-1}\cdot \text {s}^{-1})$