Study on MSO/GO-based determination method for trace amount of aqueous Hg2+.
- Author:
Tao SUN
1
;
Jue HE
;
Xu-wu XIANG
;
Xiao-lan HONG
;
Xiao-yan YAO
;
Lin-zhi ZHANG
;
Yi-yun WANG
;
Yan-ne XIE
;
Wen-he WU
;
Jian-xin LU
Author Information
- Publication Type:Journal Article
- MeSH: Biosensing Techniques; Fluorometry; Graphite; Mercury; analysis; Nanotechnology; Oligonucleotide Probes; Water
- From: Chinese Journal of Industrial Hygiene and Occupational Diseases 2013;31(10):783-786
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo establish a highly sensitive fluorometric nanobiosensor for determination of aqueous mercury ions (Hg(2+)) using optimized mercury-specific oligonucleotide (MSO) probes and graphene oxide (GO).
METHODSThe nanobiosensor was assembled by attaching the self-designed MSO(1) (5' end labeled with fluorophore carboxyfluorescein (FAM), denoted as FAM-MSO(1)) and MSO(2) to the surface of GO through strong non-covalent bonding forces. Upon the addition of Hg(2+), the formation of the T-Hg(2+)-T configuration desorbed the FAM-MSO(1) and MSO(2) from the surface of GO, resulting in a restoration of the fluorescence of FAM-MSO(1). Using the specific mispairing of T-Hg(2+)-T and the changes in fluorescent signals in solutions, quantitative analysis of Hg(2+) could be performed.
RESULTSThe average thickness of the prepared GO sheets was only 1.4 nm. For the Hg(2+) nanobiosensor, the optimum concentrations of FAM-MSO(1) and MSO(2) were both 1 µmol/L, the optimum volume of 0.5 g/L GO was 5 µL, and the limit of detection was 10 pmol/L; it had low cross-reactivity with 10 other kinds of non-specific metal ions; the fluorescence recovery efficiency was up to 65% in the re-determination of Hg(2+) after addition of Na(2)S(2)O(3).
CONCLUSIONThe MSO/GO-based nanobiosensor is convenient to operate, highly sensitive, highly specific, highly accurate, and reusable. It can be applied to determine trace amount of Hg(2+) in aqueous solutions.