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Updated: Jan 31, 2026

Synthesis of Cd-free InP/ZnS Quantum Dots Suitable for Biomedical Applications
Published on: February 6, 2016
Core-shell quantum dots coated with molecularly imprinted polymer for selective photoluminescence sensing of
Li Zheng1, Yonghong Zheng2, Yang Liu3
1Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Abstract:
A photoluminescence (PL) sensor based on core-shell quantum dots (QDs) coated with molecularly-imprinted polymer (MIP) shell was designed for the determination of perfluorooctanoic acid (PFOA) in water. PFOA is a persistent and bioaccumulating water contaminant whose detection is of great importance for ensuring safe water supplies. We demonstrate a simple method to fabricate CdTe@CdS QDs and then encapsulate them with a molecularly-imprinted silica film in a one-pot sol-gel reaction. The final composite was created by anchoring the MIP layer on the CdTe@CdS QDs using 3-aminopropyltriethoxysilane (APTES) as functional monomer and tetraethoxysilane (TEOS) as crosslinker in the presence of aqueous ammonia. The combination of QDs and MIP showed stable photoluminescence and good selectivity. The PL of the MIP-coated QDs composite was efficiently quenched when PFOA molecules occupied the templated binding sites. The composite was applied to the detection of PFOA and exhibited a good linearity in range of 0.25-15.00 µmol/L with a detection limit of 25 nmol/L (~10 ppb by mass). The proposed method has been applied successfully for the determination of trace PFOA in environmental water samples and has demonstrated its robustness in the presence of other molecules and ions.
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