Silica-based mesoporous ion-imprinted fluorescent sensors for the detection of Pb in aqueous environments

In this work, an environment-friendly core-shell material based on CDs@SiO as the core and mesoporous ion-imprinted layer as the shell was reported. As a highly sensitive and accurate fluorescent sensor for the detection of Pb in environmental water, the composition combined ion imprinting technology with quantum dots to selectively quench the fluorescence of CDs by metal coordination in the presence of Pb, and the visual change of gradually weakening blue color could be observed by the naked eye for visual detection. The mesoporous structure significantly improved the detection recognition rate of CDs@SiO@MIIPs.The molecularly imprinted sensor presented a favorable linear relationship over a Pb concentration range from 10 nmol l to 100 nmol l and a detection limit of 2.16 nmol l for Pb. The imprinting factor of the CDs@SiO@MIIPs was 5.13. The sensor has a fast detection rate, is highly selective in the identification of Pb, and can be reused up to 10 times. The applicability of the method was evaluated by the determination of Pb in spiked environmental water samples with satisfactory results.