Luminescence detection of cysteine based on Ag+-mediated conformational change of terbium ion-promoted G-quadruplex

Tan, Hongliang; Tang, Gonge; Ma, Chanjiao; Li, Qian

doi:10.1016/j.aca.2015.12.035

Cited by 18 publications

(2 citation statements)

References 45 publications

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“…They proposed that Tb 3+ can stabilize the G-quadruplex structure, but the whole complex is poorly luminescent. Ag + can disrupt the quadruplex structure enhancing the emission intensity [ 37 ]. This is very similar to our observation.…”

Section: Resultsmentioning

confidence: 99%

Label-Free Ag+ Detection by Enhancing DNA Sensitized Tb3+ Luminescence

Kleinke

Saran

Liu

2016

Sensors

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In this work, the effect of Ag+ on DNA sensitized Tb3+ luminescence was studied initially using the Ag+-specific RNA-cleaving DNAzyme, Ag10c. While we expected to observe luminescence quenching by Ag+, a significant enhancement was produced. Based on this observation, simple DNA oligonucleotide homopolymers were used with systematically varied sequence and length. We discovered that both poly-G and poly-T DNA have a significant emission enhancement by Ag+, while the absolute intensity is stronger with the poly-G DNA, indicating that a G-quadruplex DNA is not required for this enhancement. Using the optimized length of the G7 DNA (an oligo constituted with seven guanines), Ag+ was measured with a detection limit of 57.6 nM. The signaling kinetics, G7 DNA conformation, and the binding affinity of Tb3+ to the DNA in the presence or absence of Ag+ are also studied to reveal the mechanism of emission enhancement. This observation is useful not only for label-free detection of Ag+, but also interesting for the rational design of new biosensors using Tb3+ luminescence.

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Section: Resultsmentioning

confidence: 99%

Label-Free Ag+ Detection by Enhancing DNA Sensitized Tb3+ Luminescence

Kleinke

Saran

Liu

2016

Sensors

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“…5 In view of the importance of CySH, it is critical to develop fast, convenient and sensitive methods for the quantitative analysis of CySH. To date, considerable efforts have been made to develop effective techniques for the assay of CySH, including colorimetry, 4,6 fluorometry, 7,8 high-performance liquid chromatography (HPLC), 9 electrochemistry, 10,11 and gas chromatography-mass spectrometry (GC-MS). 12 However, these methods suffer from some drawbacks, such as weak stability, low sensitivity, time-consuming procedure, high cost, the utilization of professional and complicated equipment, and high technical requirements for operators.…”

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confidence: 99%

Turn Off-On Electrochemiluminescence Sensor Based on MnO₂/Carboxylated Graphitic Carbon Nitride Nanocomposite for Ultrasensitive L-Cysteine Detection

Wu¹,

Wang²,

Yang³

et al. 2019

J. Electrochem. Soc.

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An ultrasensitive and turn off-on electrochemiluminescence (ECL) sensing platform was constructed by using manganese dioxide carboxylated graphitic carbon nitride (MnO2/C-g-C3N4) nanocomposite as the probe for L-cysteine (CySH) detection. In this work, we synthesized the MnO2/C-g-C3N4 tags via a facile one-step method. The ECL of C-g-C3N4 nanosheet can be quenched by the MnO2 nanosheet due to electrochemiluminescence energy transfer (ECL-ET) from C-g-C3N4 to MnO2, C-g-C3N4 and MnO2 as the energy donor and energy acceptor, respectively. However, the addition of CySH would lead to the elimination of ECL-ET, resulting in sufficient recovery of ECL intensity because it reduced MnO2 to Mn2+. Under the optimized conditions, the fabricated biosensor exhibited a wide response to CySH in the range of 0.50 nM to 1.0 μM and a low detection limit of 0.18 nM. Moreover, this convenient sensing system can successfully detect CySH in real human urine samples with satisfactory recoveries, which could provide a new way to detect CySH quickly and sensitively.

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Luminescence determination of microRNAs based on the use of terbium(III) sensitized with an enzyme-activated guanine-rich nucleotide

et al. 2018

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A method is reported for the fluorometric quantitation of microRNA. It is making use of a luminescent probe deribed from terbium(III) ion whose fluorescence is sensitized with a guanine-rich (G-rich) nucleotide. The probe has a large Stokes' shift and strong and sharp emission bands. The assay relies on the wide substrate specificity of terminal deoxynucleotidyl transferase (TdTase), which catalyzes the formation of long G-rich nucleotides when using microRNA primer as a trigger to start the polymerization. The addition of Tb(III) induces the formation of a G-quadruplex from the G-rich nucleotide, and this strongly enhances the green fluorescence of Tb(III) (peaking at 545 nm upon photoexcitation at 290 nm). Specifically, microRNA-21 was chosen as the analyte. The fluorescence intensity of Tb(III) increases linearly in the 1 pM to 1 nM microRNA concentration range, and the detection limit is as low as 0.11 pM. The method can distinguish between family members of microRNA and performs excellently even when applied to extracts of cancer cells. Graphical abstract A fluorometric technique is reported for the determination of microRNA. It is based on signal enhancement based on the sensitization of terbium(III) via a guanine-rich nucleotide sequence. Klenow Fragment exo (KFexo) generates DNA sequence at the 3'-OH of microRNA, and terminal deoxynucleotidyl transferase (TdTase) catalyzes the formation of long G-rich nucleotides.

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Luminescence detection of cysteine based on Ag+-mediated conformational change of terbium ion-promoted G-quadruplex

Cited by 18 publications

References 45 publications

Label-Free Ag+ Detection by Enhancing DNA Sensitized Tb3+ Luminescence

Label-Free Ag+ Detection by Enhancing DNA Sensitized Tb3+ Luminescence

Turn Off-On Electrochemiluminescence Sensor Based on MnO₂/Carboxylated Graphitic Carbon Nitride Nanocomposite for Ultrasensitive L-Cysteine Detection

Luminescence determination of microRNAs based on the use of terbium(III) sensitized with an enzyme-activated guanine-rich nucleotide

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Luminescence detection of cysteine based on Ag+-mediated conformational change of terbium ion-promoted G-quadruplex

Cited by 18 publications

References 45 publications

Label-Free Ag+ Detection by Enhancing DNA Sensitized Tb3+ Luminescence

Label-Free Ag+ Detection by Enhancing DNA Sensitized Tb3+ Luminescence

Turn Off-On Electrochemiluminescence Sensor Based on MnO2/Carboxylated Graphitic Carbon Nitride Nanocomposite for Ultrasensitive L-Cysteine Detection

Luminescence determination of microRNAs based on the use of terbium(III) sensitized with an enzyme-activated guanine-rich nucleotide

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Turn Off-On Electrochemiluminescence Sensor Based on MnO₂/Carboxylated Graphitic Carbon Nitride Nanocomposite for Ultrasensitive L-Cysteine Detection