Details

Autor(en) / Beteiligte

• Chen, Guozhen
• Bai, Wushuang
• Jin, Yan
• Zheng, Jianbin

Titel

Fluorescence and electrochemical assay for bimodal detection of lead ions based on Metal–Organic framework nanosheets

Ist Teil von

• Talanta (Oxford), 2021-09, Vol.232, p.122405-122405, Article 122405

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The accurate measurement of heavy metal ions is essential for human health and environmental protection. Here, we report the design of a simple and convenient bimodal strategy for signal-on, label-free lead ion detection in environmental samples based on two-dimensional metal–organic framework (2D-MOF) nanosheets. 2D-MOFs have different affinities toward guanine-rich DNA (ssGDNA) and the G-quadruplex, allowing these structures to be distinguished. The nanosheets were also used as quenchers for fluorescent lead ion detection. Using lead ions to induce G-quadruplex formation from ssGDNA, a simple fluorescence resonance energy transfer (FRET) strategy was developed for lead ion detection; the detection limit was 3.3 nM. Based on changes in the GDNA configuration, the FRET system was converted into an electrochemical sensor for lead ion assays using an electrode modified with the 2D-MOF nanosheets. Electrochemical impedance spectroscopy showed a high sensitivity and a low limit of detection (i.e., 8.7 pM) of the electrode. The adaptability of the bimodal mechanism was verified through the successful detection of lead ions in tap water and fertilizer samples, and the method accuracy was demonstrated through inductively coupled plasma analysis. The developed bimodal device is cost-effective, highly sensitive, and allows for convenient operation, thereby rendering it a promising and reliable system for the detection of lead ions in environmental samples. Scheme 1 Schematic illustration of FRET and electrochemical Pb2+ sensor based on 2D-MOF nanosheets. [Display omitted] •A bimodal method based on 2D-MOF nanosheets was developed for the sensitive and selective detection of lead ions.•Metal–organic framework (MOF) showed 2D monolayer nanosheets.•The fabricated sensor has been applied successfully to the detection of lead ions in real tap water and fertilizer samples.