Photoelectrochemical sensor for detection Hg2 based on in situ generated MOFs-like structures

Key Words:METAL-ORGANIC-FRAMEWORK; DRUG-DELIVERY; QUANTUM DOTS; HG2 ION; PLATFORM; CDS; LUMINESCENT; PHOTOLUMINESCENCE; AMPLIFICATION; CHEMISTRY

Abstract:Trace analysis of mercury ions (Hg2 ) is of great significance to human health and environmental protection. In this work, a novel photoelectrochemical (PEC) biosensor was developed for the ultrasensitive detection of Hg2 based on the MOFs-like composite/CdS quantum dots (QDs) as photoactive substrate materials. The MOFs-like composite in situ formed by hydrophobically modified alginate (HMA) with europium ion (Eu3 ) not only offered a friendly platform for bioconjugation but also resulted in enhancing sensor photocurrent response. Furthermore, the immobilized thymidine-rich probe DNA on the MOFs-like composite surface was bent to produce a T-Hg2 -T structure in the presence of Hg2 , resulting in enlarged steric hindrance on the electrode surface and decreased the proposed biosensor PEC response. This proposed photoelectrochemical sensing system displayed selective detection of Hg2 with a linear range from 0.1 pM to 1.0 mu M with a detection limit of 0.067 pM. The utilization of semiconductor quantum dots as light-harvesting components and the MOFs-like composite as sensitizers broadens the possible design ideas for photoelectrochemical sensing systems.

Volume:1233

Issue:

Translation or Not:no