• KRISHNAN SRINIVASAN

Articles written in Bulletin of Materials Science

• A sensitive optical sensor based on DNA-labelled Si@SiO$_2$ core–shell nanoparticle for the detection of Hg$^{2+}$ ions in environmental water samples

Si@SiO$_2$ core–shell nanoparticles were proposed for the development of fluorescent mercury sensor, wh1455-1462ichalso offers a promising alternative to toxic quantum dots (QD)-based heavy metal detection tools. In this study, a sensitivefluorescent assay based on DNA-labelled Si@SiO$_2$ core–shell nanoparticles for the detection of mercury (II) in environmentalsamples was investigated. Probe DNA was conjugated on the surface of the Si@SiO$_2$ core–shell nanoparticles via 5$^{\circ}$-terminal-SH (thiol group) reaction. The detection protocol was based on the DNA hybridization resulted from the formation of mercury-mediated (thymine–Hg$^{2+}$–thymine) base pairs which leave a fluorescent QD on the surface of quartz glass. The synthesized Si@SiO$_2$ core–shell nanoparticle showed a broad emission peak with strong intensity in the UV range around 423 nm. Transmission electronic microscope (TEM) images confirmed the presence of a uniform core–shell structure with Si core nanoparticles with a particle size ranging from 70 to 80 nm and silica shell thickness of about $10\pm 2$ nm. Overall, ourfindings highlighted that the developed assay can detect Hg$^{2+}$ ions in aqueous solution as low as 0.92 nM concentration. In addition, the labelled Si@SiO$_2$ core–shell nanoparticles showed prominence sensitivity, acceptable precision, reproducibility and stability, and could be readily applied to environmental sampling systems for Hg$^{2+}$ monitoring.

• # Bulletin of Materials Science

Volume 43, 2020
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019