title: Optical aptasensors for the analysis of the vascular endothelial growth factor (VEGF).
abstract: The vascular endothelial growth factor, VEGF, is an important biomarker for different diseases and clinical disorders. We present a series of optical aptasensor-based sensing platforms for VEGF that include the following: (i) A FRET-based sensor that involves the VEGF-induced separation of aptamer-functionalized quantum dots blocked by a quencher nucleic acid (detection limit 1 nM). (ii) A FRET-based sensor based on the VEGF-induced assembly of the aptamer subunits functionalized with QDs and a dye acceptor (Cy5), respectively (detection limit 12 nM). (iii) A chemiluminescence aptasensor based on VEGF-induced assembly of a hemin/G-quadruplex catalyst (detection limit 18 nM). (iv) A chemiluminescence aptasensor based on the VEGF-stimulated assembly of two aptamer subunits into the hemin/G-quadruplex catalyst (detection limit 2.6 nM). (v) A chemiluminescence resonance energy transfer (CRET) aptasensor based on the VEGF-induced assembly of a semiconductor QDs-hemin/G-quadruplex supramolecular structure (detection limit 875 pM). Furthermore, an amplified optical aptasensor system based on the Exonuclease III (Exo III) recycling of the VEGF analyte was developed. In this system, one aptamer subunit is modified at its 5' and 3' ends with QDs and a black hole quencher, respectively. The VEGF-induced self-assembly of the aptamer subunits result in the digestion of the quencher units and the autonomous recycling of the analyte, while triggering-on the luminescence of the QDs (detection limit 5 pM). The system was implemented to analyze VEGF in human sera samples.
authors: Institute of Chemistry, The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Ronit
authors: R
authors: Freeman
authors: Julia
authors: J
authors: Girsh
authors: Amily Fang-ju
authors: AF
authors: Jou
authors: Ja-an Annie
authors: JA
authors: Ho
authors: Thomas
authors: T
authors: Hug
authors: Jens
authors: J
authors: Dernedde
authors: Itamar
authors: I
authors: Willner
mesh_terms: D052157:Aptamers, Nucleotide / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D005090:Exodeoxyribonucleases / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D054856:G-Quadruplexes; D006427:Hemin / Q000378:metabolism; D006801:Humans; D008163:Luminescent Measurements; D055620:Optical Phenomena; D045663:Quantum Dots; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis* / Q000097:blood
chemical_list: D052157:Aptamers, Nucleotide; D042461:Vascular Endothelial Growth Factor A; D006427:Hemin; D005090:Exodeoxyribonucleases; C020133:exodeoxyribonuclease III