Sensitive and Selective Detection of Mercury Ions in Aqueous Media Using an Oligonucleotide-functionalized Nanosensor and SERS Chip

Abstract

A surface-enhanced Raman scattering (SERS) platform for the selective trace analysis of Hg 2+ ions was reported, based on poly-thymine (T) aptamer/2-naphthalenethiol (2-NT)-modified gold nanoparticles (AuNPs), which was an oligonucleotide-functionalized nanosensor and SERS chip. 2-NT was used as a Raman reporter, and T aptamer could form a T-Hg 2+ -T structure with Hg 2+ ions making an SERS nanosensor absorbed to the SERS chip. The optimum concentrations of DNA and 2-NT were obtained. An average of 960 DNA molecules attached to each AuNP were measured. The limit of detection (LOD) was 1.0 ppt (1.0 × 10 -12 g/mL), which is far below the limit of 10.0 ppb for drinking water, stipulated by the World Health Organization. The sensor has the advantages of low detection cost, a simple sample pretreatment, a green solution and reducing false positives. Furthermore, the nanosensor was used for the determination of trace Hg 2+ in the water of a lake; a reliable result was obtained accurately.

Captivating nano sensors for mercury detection: a promising approach for monitoring of toxic mercury in environmental samples

“…This nanosensor exhibits a LOD of 1.0 ppt (1.0 × 10 −12 g mL −1 ), which is much lower than the WHO's recommended drinking water level of 10.0 ppb. 85 Similarly, as illustrated in Scheme 4 , Sarfo and Sivanesan et al devised a SERS sensor by conjugating aminodibenzo-18-crown-6 with mercaptopropionic acid. The resulting crown ether derivative (TCE) self-assembled on the surface of the gold nanostructure of the substrate to form a distinct surface layer for Hg( ii ) ions.…”

Rapid and Sensitive Surface-enhanced Raman Spectroscopy Method for Determination of Ketamine in Urine

“…The repeatability and stability of the experiment are also an important parameter when performing SERS detection of ketamine. 26,27 Under the above-mentioned optimal detection conditions, the repeatability of SERS detection for ketamine aqueous solution at a concentration of 5 ppm was conducted, as demonstrated in Fig. 3(a).…”

Sensors with Highly Ordered Nucleotides

“…Zou et al reported on a surface-enhanced Raman scattering (SERS) platform for the selective trace analysis of Hg 2+ based on poly-thymine (T) aptamer/2naphthalenethiol (2-NT)-modified Au nanoparticles. 7 T aptamer forms a T-Hg 2+ -T structure with Hg 2+ , and 2-NT was used as a Raman reporter. The detection limit was 1.0 ppt, far below the limit of 10.0 ppb for drinking water required by the WHO.…”