title: Enhancement of the Upconversion Emission by Visible-to-Near-Infrared Fluorescent Graphene Quantum Dots for miRNA Detection.
abstract: We developed a sensor for the detection of specific microRNA (miRNA) sequences that was based on graphene quantum dots (GQDs) and ssDNA-UCNP@SiO2. The proposed sensor exploits the interaction between the sp(2) carbon atoms of the GQD, mainly π-π stacking, and the DNA nucleobases anchored on the upconversion nanoparticles (UCNPs). This interaction brings the GQD to the surface of the ssDNA-UCNP@SiO2 system, enhancing the upconversion emission. On the other hand, hybridization of the single-stranded DNA (ssDNA) chains anchored on the nanoparticles with their complementary miRNA sequences blocks the capacity of the UCNPs to interact with the GQD through π-π stacking. That gives as result a reduction of the fluorescent enhancement, which is dependent on the concentration of miRNA sequences. This effect was used to create a sensor for miRNA sequences with a detection limit of 10 fM.
authors.affiliation: Department of Physical Chemistry II, Faculty of Pharmacy, Complutense University of Madrid , 28040 Madrid, Spain.
authors.forename: Marco
authors.initials: M
authors.lastname: Laurenti
authors.affiliation: Department of Physical Chemistry II, Faculty of Pharmacy, Complutense University of Madrid , 28040 Madrid, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Paez-Perez
authors.affiliation: Department of Inorganic Chemistry. Faculty of Science, University of Málaga , 29071 Málaga, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Algarra
authors.affiliation: Department of Physical Chemistry II, Faculty of Pharmacy, Complutense University of Madrid , 28040 Madrid, Spain.
authors.forename: Paulino
authors.initials: P
authors.lastname: Alonso-Cristobal
authors.affiliation: Department of Physical Chemistry II, Faculty of Pharmacy, Complutense University of Madrid , 28040 Madrid, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Lopez-Cabarcos
authors.affiliation: Department of Physical Chemistry II, Faculty of Pharmacy, Complutense University of Madrid , 28040 Madrid, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Mendez-Gonzalez
authors.affiliation: Department of Physical Chemistry II, Faculty of Pharmacy, Complutense University of Madrid , 28040 Madrid, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Rubio-Retama
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D005453:Fluorescence; D006108:Graphite / Q000737:chemistry*; D035683:MicroRNAs / Q000032:analysis*; D053758:Nanoparticles / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D035683:MicroRNAs; D012822:Silicon Dioxide; D006108:Graphite
keywords: energy transfer; graphene quantum dots; miRNA sensor; nanoparticles; upconversion