Inhibition Assay of Biomolecules based on Fluorescence Resonance Energy Transfer (FRET) between Quantum Dots and Gold Nanoparticles

Abstract

An inhibition assay method was developed based on the modulation in the FRET efficiency between quantum dots (QDs) and gold nanoparticles (AuNPs) in the presence of the molecules which inhibit the interactions between QD- and AuNP-conjugated biomolecules. For the functionalization, AuNPs were first stabilized by chemisorption of n-alkanethiols and then capped with the first generation polyamidoamine (G1 PAMAM) dendrimers. By employing a streptavidin-biotin couple as a model system, avidin was quantitatively analyzed as an inhibitor by sensing the change in photoluminescence (PL) quenching of SA-QDs by biotin-AuNPs. The detection limit for avidin was about 10 nM. It is anticipated that the PL quenching-based sensing system can be used for the quantitative analysis and high throughput screening of molecules which inhibit the specific biomolecular interactions.

Novel synthesis of Au nanoparticles using fluorescent carbon nitride dots as photocatalyst

“…Indeed, substantial fluorescence quenching is observed for the CNDs-HAuCl 4 mixture after UV irradiation (ESM Fig. S2), which can be attributed to the fact that some CNDs are associated with the AuNPs formed; subsequently, fluorescence quenching occurs with the fluorescence resonance energy transfer between CNDs and AuNPs [30]. The residual fluorescence observed originates from free CNDs existing in the dispersion.…”

Simultaneous Detection of Multi-DNAs and Antigens Based on Self-Assembly of Quantum Dots and Carbon Nanotubes

“…QD PL quenching may occur by several mechanisms (Fan and Jones Jr, 2006;Pan et al, 2006c): (1) dynamic quenching, (2) static quenching, (3) quenching by energy transfer, and (4) charge-transfer reactions. In this paper we can draw the conclusion that QD quenching in the presence of CNTs is mainly caused by dynamic quenching and energy-transfer mechanisms (Clapp et al, 2004;Oh et al, 2005). When quenching occurs by a dynamic mechanism, the quenching is an additional process that deactivates the excited state besides radiative emission (Cui et al, 2004b).…”

Preparation of fluorescent DNA probe by solid-phase organic synthesis

“…As novel luminescent inorganic fluorophores, Quantum dots (QDs) are currently being widely used in biological probes, in vitro assay detection, in vivo cell labeling and imaging, because QDs show a broad and continuous excitation spectrum, narrow size-tunable symmetric emission spectrum and high fluorescence quantum yield [3][4][5][6][7][8]. Recently, complex nanostructures formed by linking QDs as energy donors and gold nanoparticles (AuNPs) as energy acceptors through DNA hybridization or streptavidin-biotin interaction have also been realized [9][10][11][12][13] and applied in the sensing biomolecular concentration [10]. AuNPs have a high extinction coefficient and a broad absorption spectrum in visible light that is overlapped by the emission wavelength of the usual energy donors.…”