Electrochemiluminescence Sensor Based on CeO[sub.2] Nanocrystalline for Hg[sup.2+] Detection in Environmental Samples

• Published in: Molecules (Basel, Switzerland) Vol. 29; no. 1
• Main Authors: Tian, Chunyuan, Tang, Feiyan, Guo, Wei, Wei, Minggang, Wang, Li, Zhuang, Xuming, Luan, Feng
• Format: Journal Article
• Language: English
• Published: MDPI AG 01.12.2023
• Subjects: Sensors; China
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules29010001

The excessive concentration of heavy-metal mercury ions (Hg[sup.2+]) in the environment seriously affects the ecological environment and even threatens human health. Therefore, it is necessary to develop rapid and low-cost determination methods to achieve trace detection of Hg[sup.2+]. In this paper, an Electrochemiluminescence (ECL) sensing platform using a functionalized rare-earth material (cerium oxide, CeO[sub.2]) as the luminescent unit and an aptamer as a capture unit was designed and constructed. Using the specific asymmetric matching between Hg[sup.2+] and thymine (T) base pairs in the deoxyribonucleic acid (DNA) single strand, the “T−Hg−T” structure was formed to change the ECL signal, leading to a direct and sensitive response to Hg[sup.2+]. The results show a good linear relationship between the concentration and the response signal within the range of 10 pM–100 µM for Hg[sup.2+], with a detection limit as low as 0.35 pM. In addition, the ECL probe exhibits a stable ECL performance and excellent specificity for identifying target Hg[sup.2+]. It was then successfully used for spiked recovery tests of actual samples in the environment. The analytical method solves the problem of poor Hg[sup.2+] recognition specificity, provides a new idea for the efficient and low-cost detection of heavy-metal pollutant Hg[sup.2+] in the environment, and broadens the prospects for the development and application of rare-earth materials.