Fluorescence quenching of MoS2 nanosheets/DNA/silicon dot nanoassembly: effective and rapid detection of Hg2+ ions in aqueous solution
- 255 Downloads
Mercury (Hg) contamination of aquatic sites represents a serious risk for human health and the environment. Therefore, effective and rapid monitoring of Hg in aqueous samples is a challenge of timely importance nowadays. In the present study, a rapid and sensitive mercury sensor based on the fluorescence quenching of MoS2 nanosheets/DNA/silicon dot nanoassembly has been developed for the efficient detection of mercury(II) in aquatic environments. In this process, silicon dots were synthesized through one-step high-temperature calcinations and thermomagnesium reduction method at 900 °C using rice husk as a silicon source, which demonstrates superior photophysical properties and excitation-dependent fluorescence behavior. The interaction between MoS2 nanosheets/DNA/silicon dot nanoassembly and Hg2+ ions was studied using photoluminescence spectroscopy. The addition of Hg2+ ions to the assay solution induced the detachment of fluorescent probe from the surface of MoS2 nanosheets. Thus, the fluorescent probes sustained its fluorescence intensity. The developed sensor was tested on various concentrations of Hg2+ ions ranging from 0 to 1000 nM as well as on various metal ions. In addition, MoS2 nanosheets/DNA/silicon dot nanoassembly fluorescent Hg sensor efficiently detected the presence of Hg2+ ions in real-time water samples, which was comparably detected by the conventional atomic absorbance spectrometer (AAS). Overall, our results highlighted the high reliability of the present approach for environmental monitoring of Hg2+ ions, if compared to that of the customary method with a lowest detection limit of 0.86 nM.
KeywordsMercury MoS2 nanosheets Fluorescence Nanoassembly Silicon dots FRET
K. Dinakaran acknowledges the financial support of SERB, Department of Science and Technology, New Delhi, India, through Grant No. EEQ/2016/000049.
- Coleman JN, Lotya M, O'Neill A, Bergin SD, King PJ, Khan U, Young K, Gaucher A, De S, Smith RJ, Shvets IV, Arora SK, Stanton G, Kim HY, Lee K, Kim GT, Duesberg GS, Hallam T, Boland JJ, Wang JJ, Donegan JF, Grunlan JC, Moriarty G, Shmeliov A, Nicholls RJ, Perkins JM, Grieveson EM, Theuwissen K, McComb DW, Nellist PD, Nicolosi V (2011) Two-dimensional nanosheet produced by liquid exfoliation of layered materials. Science 331:568–571. https://doi.org/10.1126/science.1194975 CrossRefGoogle Scholar
- Fujioka K, Hiruoka M, Sato K, Manabe N, Miyasaka R, Hanada S, Hoshino A, Tilley RD, Manome Y, Hirakuri K (2008) Luminescent passive-oxidized silicon quantum dots as biological staining labels and their cytotoxicity effects at high concentration. Nanotechnology 19:415102. https://doi.org/10.1088/0957-4484/19/41/415102 CrossRefGoogle Scholar
- Ji Q, Bowei L, Xinran W, Zhong Z, Zhuo W, Jinglong H, Lingxin C (2017) Three-dimensional paper-based microfluidic 1 chip device for multiplexed fluorescence detection of Cu2+ and Hg2+ ions based on ion imprinting technology. Sens Actuators B Chem 251:224–233. https://doi.org/10.1016/j.snb.2017.05.052 CrossRefGoogle Scholar
- Murugan K, Nataraj D, Jaganathan A, Dinesh D, Jayashanthini S, Samidoss CM, Paulpandi M, Panneerselvam C, Subramaniam J, Aziz AT, Nicoletti M, Kumar S, Higuchi A, Benelli G (2017) Nanofabrication of graphene quantum dots with high toxicity against malaria mosquitoes, Plasmodium falciparum and MCF-7 cancer cells: impact on predation of non-target tadpoles, odonate nymphs and mosquito fishes. J Clust Sci 28:393–411. https://doi.org/10.1007/s10876-016-1107-7 CrossRefGoogle Scholar
- Prasad PN (2004) Nanophotonics. Wiley-Interscience, New York ISBN: 978-0-471-64988-5. https://www.wiley.com/en-us/Nanophotonics-p-9780471649885 CrossRefGoogle Scholar