Silica-Coated Silver Nanoparticles Decorated with Fluorescent CdTe Quantum Dots and DNA Aptamers for Detection of Tetracycline

Abstract

An aptamer-labelled fluorescent nanoprobe-integrated shellisolated nanoparticle-enhanced fluorescence spectroscopy (SHINEFs) had been proposed for selective and sensitive detection of Tc. In the study, CdTe quantum dots were used as a fluorescent source; silica-coated silver nanoparticles (Ag@SiO 2 ) were used as the SHINEFs material for signal amplification. The maximum SHINEFs was obtained with a 9 nm silica spacer. The linear range of the nanoprobe was from 0.2 to 400 μM, and the detection limit was 16.2 nM. Furthermore, our synthesized nanoprobe was applied to detect Tc in milk with a recovery rate of 96.50−101.80%. These results showed that the as-prepared nanoprobe was a rapid detection tool for Tc with high sensitivity and selectivity. The aptamer-modified nanoprobe can also be applied to the analysis of other substances by altering the aptamer.

Green synthetic nitrogen-doped graphene quantum dot fluorescent probe for the highly sensitive and selective detection of tetracycline in food samples

“…The fluorescence intensity diminishes dramatically, if the pH value reaches this range, as the surface bound carboxyl groups are protonated in an acidic environment and the hydroxide ions are protonated in alkaline media, resulting in a decrease in the fluorescence intensity of the system. 53 Therefore, we used the N-GQDs/TC solution system with pH = 7.0 in a neutral environment for the next experimental exploration.…”

Synthesis and Application of Silica-Coated Quantum Dots in Biomedicine

“…Interestingly, QD-based nanostructures can also be used as detection probes for Tc, which is a broad-spectrum tetracycline antibiotic. Xueqing et al [ 54 ], for example, used aptamer-labeled fluorescent nanoprobe-integrated shell-isolated NP-enhanced fluorescence spectroscopy (SHINEFs) for Tc detection ( Figure 3 b). The authors introduced silica-coated Ag (Ag@SiO 2 ) NPs to produce fluorescence (Ag@SiO 2 /QDs), and an aptamer was added to the QD surfaces (Ag@SiO 2 /QDs-Apt) to ensure highly sensitive detection.…”

“…( b ) QD-embedded silica-coated Ag NPs (Ag@SiO 2 /QDs) and attached aptamer (Ag@SiO 2 /QDs-Apt). Tc detection using shell-isolated NP-enhanced fluorescence (SHINEF) [ 54 ]. ( c ) Detection of zealralenone (ZEN) and deoxynivalenol (DON) using LFIA with QD@SiO 2 [ 55 ].…”

ZnS quantum dots as fluorescence sensor for quantitative detection of tetracycline

“…Indirect detection relying on the fact that Eu 3+ or Al 3+ can bind specifically with TC has been reported [11,[20], however these sensors were found to be complex [21] and exhibited a narrower linear range of TCs compared to direct sensors [1]. Aptamers-based fluorescent sensors have been designed for the detection of TC [22]. Nevertheless, despite their high affinity, these approaches involve tedious DNA labeling or modification techniques based on condensation reactions between the carboxyl group and the amino group, or streptavidin-biotin specific reaction, which make these processes technically demanding, time consuming, expensive in terms of reagents that may also affect the affinity of the aptamer [23].…”