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Nicking enzyme-assisted signal-amplifiable Hg2+ detection using upconversion nanoparticles.

ABSTRACT: A highly specific and sensitive isothermal method for mercury detection using DNA-conjugated upconversion nanoparticles is reported. A single-stranded DNA containing thymine bases, used as the Hg2+-capturing element through the formation of thymine-Hg2+-thymine complex, is covalently attached to the NaYF4: Yb3+, Tm3+ nanoparticles. Luminescence resonance energy transfer takes place between the NaYF4: Yb3+, Tm3+ nanoparticles as donor and DNA-intercalating SYBR Green I as the acceptor upon excitation of 980?nm. The sensitivity and selectivity toward Hg2+ are enhanced using the nicking enzyme, Nt. Alwl, which leads to signal amplification. By monitoring the ratio of acceptor emission to a reference peak, the presence of Hg2+ ions are quantitatively determined with a lower detection limit of 0.14?nM, which is much lower than the US Environmental Protection Agency (EPA) limit of Hg2+ in drinking water.

SUBMITTER: Vijayan AN

PROVIDER: S-EPMC6546430 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Nicking enzyme-assisted signal-amplifiable Hg2+ detection using upconversion nanoparticles.

Vijayan Anjaly N AN Liu Zhiming Z Zhao Haohan H Zhang Peng P

Analytica chimica acta 20190504

A highly specific and sensitive isothermal method for mercury detection using DNA-conjugated upconversion nanoparticles is reported. A single-stranded DNA containing thymine bases, used as the Hg2+-capturing element through the formation of thymine-Hg2+-thymine complex, is covalently attached to the NaYF4: Yb3+, Tm3+ nanoparticles. Luminescence resonance energy transfer takes place between the NaYF4: Yb3+, Tm3+</su ...[more]

PMID: 31146867

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