Multi-functional electrochemiluminescence aptasensor based on resonance energy transfer between Au nanoparticles and lanthanum ion-doped cadmium sulfide quantum dots
| Autor: | Min Chen, Jingling Wu, Yingzi Fu, Cun Wang, Fangjing Mo |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Photoluminescence
010401 analytical chemistry Surface plasmon Doping Nanoparticle 02 engineering and technology 021001 nanoscience & nanotechnology Photochemistry 01 natural sciences Biochemistry Cadmium sulfide 0104 chemical sciences Analytical Chemistry chemistry.chemical_compound chemistry Colloidal gold Quantum dot Environmental Chemistry Electrochemiluminescence 0210 nano-technology Spectroscopy |
| Zdroj: | Analytica Chimica Acta. 1086:66-74 |
| ISSN: | 0003-2670 |
| DOI: | 10.1016/j.aca.2019.08.012 |
| Popis: | Novel lanthanum ion-doped cadmium sulfide quantum dots (CdS:La QDs) were synthesized and characterized by transmission electron microscopy (TEM) and photoluminescence (PL). Based on CdS:La QDs as the electrochemiluminescence (ECL) luminophores, a distance-dependent ECL intensity enhanced or quenched system between CdS:La QDs and gold nanoparticles (Au NPs) was designed. Firstly, ssDNA 1 was linked to the CdS:La QDs modified glassy carbon electrode via amide bond. Then the prepared Au NP–ssDNA 2 conjugates were used to hybridize with ssDNA 1, the surface plasmon resonances (SPR) of Au NPs enhanced ECL intensity (signal on) while Au NPs and CdS:La QDs were separated at a certain distance. Secondly, In the presence of Hg2+, the oligonucleotide conformation changed from linear chain to hairpin due to the thymine–Hg2+–thymine (T–Hg2+–T) base pairs. ECL quenching (signal off) achieved lie in resonance energy transfer (RET) between the CdS:La QDs and the proximal Au NPs at a close distance. Finally, after being incubated with TB, a strong and stable TB–aptamer complex was generated, which led to the release of Au NP–ssDNA 2 conjugates. The ECL signal of the CdS:La QDs was ultimately recovered (signal on again). The “on–off–on” approach was used to detect Hg2+ and TB, sensitively and respectively. The line ranges were 1.00 × 10−12 –1.00 × 10−5 mol L−1 and 1.00 × 10−16 –1.00 × 10−6 mol L−1, respectively. The low limits of detection (S/N = 3) were at 3.00 × 10−13 mol L−1 and 3.00 × 10−17 mol L−1. Moreover, the ECL sensor exhibited high selectivity and good stability, and was successfully applied to the detection of TB in real sample. |
| Databáze: | OpenAIRE |
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