Aptamer-Pendant DNA Tetrahedron Nanostructure Probe for Ultrasensitive Detection of Tetracycline by Coupling Target-Triggered Rolling Circle Amplification

Abstract

Tetracycline (TET) is a broad-spectrum antibiotic, which is frequently used in the prevention and treatment of animal diseases, feed additives, and so on. However, its residue and accumulation in animal-derived foods could cause several side effects to the human body. Herein, we fabricated TET aptamerpendant DNA tetrahedral nanostructure-functionalized magnetic beads (Apt-tet MBs) as a probe to detect TET. In the presence of target TET, DNA primer was released from Apt-tet MBs since the TET aptamer could specifically bind TET. Next, the separated DNA primer could effectively initiate rolling circle amplification (RCA) reaction and generate a long tandem single-stranded sequence. Finally, with SYBR Green I as the fluorescence dye, the fluorescence signal could be detected by detection probes through hybridizing the RCA product. Under optimal conditions, the fluorescent signal increased with the increasing target TET concentration within the 5 orders of magnitude dynamic range from 0.001 to 10 ng mL −1 . The detection limit was calculated to be 0.724 pg mL −1 and the method showed high selectivity toward TET among different antibiotics. More impressively, this method was employed for TET determination in fish and honey samples. The as-obtained results were consistent with those of ELISA kits, holding great potential in the field of food analysis.

Colorimetric determination of tetracyclines based on aptamer-mediated dual regulation of gold nanoparticle aggregation and in situ silver metallization

“…The concentration of the AuNPs was calculated to be 4.24 × 10 −9 mol L −1 based on the Lambert–Beer law ( ε 450 = 7.2 × 10 6 L (mol cm) −1 ). 29…”

Organic–Inorganic Hybrid Near-Infrared Emitting Porous Polymer for Detection and Photodegradation of Antibiotics

“…Recently, fluorescence detection has been widely applied to detection of antibiotics because of its facile operation and high sensitivity. 12 In addition, various techniques for removing antibiotics from water involve catalysis, adsorption, membrane separation, etc. 13−15 In water pollution control, catalysis treatment has also been recognized as a convenient and efficient method.…”

“…To detect antibiotics, high-performance liquid chromatography (HPLC), electrochemical, or voltammetric analyses have been used. − These methods are accurate and sensitive, but the analysis is restricted to laboratories and rapid screening is not possible. Recently, fluorescence detection has been widely applied to detection of antibiotics because of its facile operation and high sensitivity . In addition, various techniques for removing antibiotics from water involve catalysis, adsorption, membrane separation, etc. − In water pollution control, catalysis treatment has also been recognized as a convenient and efficient method .…”

DNA Aptamer-Conjugated Magnetic Graphene Oxide for Pathogenic Bacteria Aggregation: Selective and Enhanced Photothermal Therapy for Effective and Rapid Killing

“…Although gold-based nanostructures with certain morphologies (rod, shell, cages, and roses) have been used as effective PTT agents, − biocompatibility, one-step preparation, and easy functionalization make GO an ideal candidate for PTT. − However, to provide effective and efficient PTT, active targeting is an indispensable requirement. To date, several targeting ligands including DNA/RNA aptamers, antibodies, RGD peptides, and boronic acids have been actively used for active targeting by researchers. − …”

“…Aptamers composed of DNA or RNA generated by the process called systematic evolution of ligands by exponential enrichment (SELEX) toward several different targets including metal ions, small molecules, protein, virus, bacteria, and cancer cells have been attractively used. − Among targeting ligands, aptamers have quite advantages owing to their easy modification with various functional groups, great stability in experimental conditions, and high specificity and affinity (with nanomolar). , …”