A fluorescent probe based on FRET effect between carbon nanodots and gold nanoparticles for sensitive detection of thiourea

Gold Nanoparticles as a Biosensor for Cancer Biomarker Determination

“…Dadmehr [41] et al conjugated the aptamers to deposit on the surface of graphene oxide decorated with AuNPs, and the following formation of a hetero-duplex stem-loop structure led to fluorescence quenching. Moreover, Hu et al [42] also reported a sensitive fluorescent probe with off-on FRET response for harmful thiourea that can be detected by fluorescent carbon nanodots combined with AuNPs via electrostatic interaction. As shown in Figure 4a, the electromagnetic field generated by the long-axis absorption peak of AuNPs very strongly absorbs photons, which consequently enhances the absorption rate of photons via the surrounding upconversion nanoparticles, thus increasing the intensity of the emitted light.…”

A Highly Sensitive Dual-Signal Strategy via Inner Filter Effect between Tween 20-Gold Nanoparticles and CdSe/ZnS Quantum Dots for Detecting Cu2+

“…Quantum dots (QDs) have become a research hotspot because of their excellent photophysical properties, for example, tunable and narrow emission spectrum, high quantum yield, and high stability and photobleaching threshold [ 15 ]. Benefiting from these properties, QDs have been widely used as photocatalysts [ 16 , 17 ], photoelectric devices [ 18 ], biological imaging [ 19 ] and fluorescent probes [ 20 ]. Due to the excellent properties of QDs and the high extinction coefficient of AuNPs, various novel fluorescence sensors are composed of AuNPs and QDs, which are developed for the detection of thiourea [ 20 ], cysteine [ 21 ], and organophosphorus pesticide [ 22 ].…”

“…Benefiting from these properties, QDs have been widely used as photocatalysts [ 16 , 17 ], photoelectric devices [ 18 ], biological imaging [ 19 ] and fluorescent probes [ 20 ]. Due to the excellent properties of QDs and the high extinction coefficient of AuNPs, various novel fluorescence sensors are composed of AuNPs and QDs, which are developed for the detection of thiourea [ 20 ], cysteine [ 21 ], and organophosphorus pesticide [ 22 ]. Most of them are based on fluorescence resonance energy transfer (FRET), in which QDs are considered to be ideal fluorescent donors, and AuNPs are outstanding absorbers.…”