Optical fiber sensor for Hg(II) based on carbon dots

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Helena M R Goncalves (Author) Other; Abel J Duarte (Author) Other; Joaquim C G E Esteves da Silva (Author) FCUP

Journal

Title: Biosensors and Bioelectronics

Vol. 26 No. 4

Pages: 1302-1306

ISSN: 0956-5663

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 183 Citations

Scopus - 199 Citations

Scientific classification

FOS: Engineering and technology > Nano-technology

Other information

Authenticus ID: P-003-02K

DOI: 10.1016/j.bios.2010.07.018

Abstract (EN): An optical fiber sensor for Hg(II) in aqueous solution based on sol-gel immobilized carbon dots nanoparticles functionalized with PEG(200) and N-acetyl-t-cysteine is described. This sol-gel method generated a thin (about 750 nm), homogenous and smooth (roughness of 2.7 +/- 0.7 a) film that immobilizes the carbon dots and allows reversible sensing of Hg(II) in aqueous solution. A fast (less than 10 s), reversible and stable (the fluorescence intensity measurements oscillate less than 1% after several calibration cycles) sensor system was obtained. The sensor allow the detection of submicron molar concentrations of Hg(II) in aqueous solution. The fluorescence intensity of the immobilized carbon dots is quenched by the presence of Hg(II) with a Stern-Volmer constant (pH = 6.8) of 5.3 x 10(5) M(-1).

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5