Person: Melle Hernández, Sonia
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First Name
Sonia
Last Name
Melle Hernández
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Óptica
Area
Optica
Identifiers
20 results
Search Results
Now showing 1 - 10 of 20
Item Oligonucleotide Sensor Based on Selective Capture of Upconversion Nanoparticles Triggered by Target Induced DNA Inter-Strand Ligand Reaction(ACS applied materials & interfaces, 2017) Méndez González, Diego; Laurenti, Marco; Latorre, Alfonso; Somoza, Álvaro; Vázquez, Ana; Negredo, Ana Isabel; López Cabarcos, Enrique; Calderón, Oscar Gómez; Melle Hernández, Sonia; Rubio Retama, JorgeWe present a sensor that exploits the phenomenon of upconversion luminescence to detect the presence of specific sequences of small oligonucleotides like miRNAs among others. The sensor is based on NaYF4:Yb,Er@SiO2 nanoparticles functionalized with ssDNA that contain azide groups on the 3' ends. In the presence of a target sequence, inter-strand ligation is possible via click-reaction between one azide of the upconversion probe and a DBCO-ssDNA-biotin probe present in the solution. As result of this specific and selective process, biotin is covalently attached to the surface of the upconversion nanoparticles. The presence of biotin on the surface of the nanoparticles allows their selective capture on a streptavidin-coated support, giving a luminescent signal proportional to the amount of target present in the test samples. With the aim of studying the analytical properties of the sensor, total RNA samples were extracted from healthy mosquitoes and spiked-in with a specific target sequence at different concentrations. The result of these experiments revealed that the sensor was able to detect 10-17 moles (100 fM) of the target sequence in mixtures containing 100 ng of total RNA per well. Similar limit of detection was found for spiked human serum samples, demonstrating its suitability for detecting specific sequences of small oligonucleotides under real conditions. By contrast, under the presence of non-complementary sequences or sequences having mismatches, the luminescent signal was negligible or conspicuously reduced.Item Líneas de investigación del Grupo UCM de Física del Láser, Óptica Cuántica y Óptica No Lineal(Óptica Pura y Aplicada, 2011) Antón Revilla, Miguel Ángel; Arrieta Yáñez, Francisco; Cabrera Granado, Eduardo; Carreño Sánchez, Fernando; Ezquerro Rodríguez, José Miguel; Gómez Calderón, Óscar; Gonzalo Fonrodona, Isabel; Guerra Pérez, José Manuel; Melle Hernández, Sonia; Soler Rus, Miguel Odín; Sánchez Balmaseda, Margarita María; Weigand Talavera, Rosa MaríaEn este trabajo presentamos las líneas de investigación del Grupo de Física del Láser, Óptica Cuántica y Óptica No Lineal de la UCM. La investigación comprende trabajos experimentales y teóricos en el desarrollo de prototipos de láser, análisis de inestabilidades espacio-temporales en láseres de gran apertura, el estudio de propagación de radiación en régimen de luz lenta y de pulsos ultracortos en medios resonantes y no resonantes, la generación de radiación por procesos no lineales y el estudio de memorias ópticas por eco fotónico.Item Dynamic population gratings in highly doped erbium fibers(Journal of the Optical Society of America B, 2011) Melle Hernández, Sonia; Gómez Calderón, Óscar; Zhuo, Zhong C.; Antón Revilla, Miguel Ángel; Carreño Sánchez, FernandoThe efficiency of the dynamic population gratings recorded in highly doped erbium fibers has been studied. We find that the grating response increases with optical density, although the presence of erbium ion pairs in fibers with ion density of the order of 6:3 × 1025 m−3 degrades the grating efficiency. The experimental results have been reproduced including inhomogeneous upconversion processes in the nonlinear coupled-wave equations.Item Control of upconversion luminescence by gold nanoparticle size: from quenching to enhancement(Nanoscale, 2019) Méndez González, Diego; Melle Hernández, Sonia; Gómez Calderón, Óscar; Laurenti, Marco; Cabrera Granado, Eduardo; Egatz-Gómez, Ana; López Cabarcos, Enrique; Rubio Retama, Jorge; Díaz García, ElenaMetallic nanostructures have the potential to modify the anti-Stokes emission of upconverting nanoparticles (UCNPs) by coupling their plasmon resonance with either the excitation or the emission wavelength of the UCNPs. In this regard gold nanoparticles (AuNPs) have often been used in sensors for UCNP luminescence quenching or enhancement, although systematic studies are still needed in order to design optimal UCNP–AuNP based biosensors. Amidst mixed experimental evidence of quenching or enhancement, two key factors arise: the nanoparticle distance and nanoparticle size. In this work, we synthesize AuNPs of different sizes to assess their influence on the luminescence of UCNPs. We find that strong luminescence quenching due to resonance energy transfer is preferentially achieved for small AuNPs, peaking at an optimal size. A further increase in the AuNP size is accompanied by a reduction of luminescence quenching due to an incipient plasmonic enhancement effect. This enhancement counterbalances the luminescence quenching effect at the biggest tested AuNP size. The experimental findings are theoretically validated by studying the decay rate of the UCNP emitters near a gold nanoparticle using both a classical phenomenological model and the finite-difference time-domain method. Results from this study establish general guidelines to consider when designing sensors based on UCNPs–AuNPs as donor–quencher pairs, and suggest the potential of plasmon-induced luminescence enhancement as a sensing strategy.Item FRET distance dependence from upconverting nanoparticles to quantum dots(Journal of physical chemistry C, 2018) Melle Hernández, Sonia; Gómez Calderón, Óscar; Laurenti, Marco; Méndez González, Diego; Egatz-Gómez, Ana; López Cabarcos, Enrique; Cabrera Granado, Eduardo; Díaz García, Elena; Rubio Retama, JorgeFörster resonant energy transfer (FRET) with upconverting nanoparticles (UCNPs) as donors and quantum dots (QDs) as acceptors has been regarded as a promising tool for biosensing applications. In this work, we use time-resolved fluorescence spectroscopy to analyze the UCNP-to-QD FRET and we focus on the most relevant parameter of the FRET phenomenon, UCNP-QD distance. This distance is controlled by a nanometric silica shell around the UCNP surface. We theoretically reproduce the experimental results applying FRET theory to the distribution of emitting erbium ions in the UCNP. This simple model allows us to estimate the contribution of every erbium ion to the final FRET response and to explore different strategies to improve FRET efficiency.Item Homogeneous broadening effect on temperature dependence of green upconversion luminescence in erbium doped fibers(Journal of Luminescence, 2013) Egatz-Gómez, Ana; Gómez Calderón, Óscar; Melle Hernández, Sonia; Carreño Sánchez, Fernando; Antón Revilla, Miguel Ángel; Gort, Elske M.We study the green upconversion luminescence of Er3+ ions in an aluminosilicate optical fiber upon near infrared excitation at 787 nm. The dependence of the upconversion luminescence on temperature has been determined. As temperature drops from room to cryogenic temperatures, the upconversion green emission reaches a maximum around 40 K, and then decreases. A nearly quadratic dependence of the upconversion luminescence with excitation power is found, which is consistent with a sequential stepwise two-photon absorption process. These results have been explained with a semiclassical model that considers the inhomogeneous broadening of the optical transitions due to glass imperfections, and the dependence of the homogeneous linewidth broadening on temperature.Item Plasmon-enhanced terahertz emission in self-assembled quantum dots by femtosecond pulses(Journal of Applied Physics, 2014) Carreño Sánchez, Fernando; Antón Revilla, Miguel Ángel; Melle Hernández, Sonia; Gómez Calderón, Óscar; Cabrera Granado, Eduardo; Cox, Joel; Singh, Mahi R.; Egatz-Gómez, AnaA scheme for terahertz (THz) generation from intraband transition in a self-assembled quantum dot (QD) molecule coupled to a metallic nanoparticle (MNP) is analyzed. The QD structure is described as a three-level atom-like system using the density matrix formalism. The MNP with spherical geometry is considered in the quasistatic approximation. A femtosecond laser pulse creates a coherent superposition of two subbands in the quantum dots and produces localized surface plasmons in the nanoparticle which act back upon the QD molecule via dipole-dipole interaction. As a result, coherent THz radiation with a frequency corresponding to the interlevel spacing can be obtained, which is strongly modified by the presence of the MNP. The peak value of the terahertz signal is analyzed as a function of nanoparticle's size, the MNP to QD distance, and the area of the applied laser field. In addition, we theoretically demonstrate that the terahertz pulse generation can be effectively controlled by making use of a train of femtosecond laser pulses. We show that by a proper choice of the parameters characterizing the pulse train a huge enhancement of the terahertz signal is obtained.Item Radiation emission from an asymmetric quantum dot coupled to a plasmonic nanostructure(Journal of Optics, 2016) Antón Revilla, Miguel Ángel; Carreño Sánchez, Fernando; Gómez Calderón, Óscar; Melle Hernández, Sonia; Cabrera Granado, EduardoWe propose a scheme for controlling the absorption and RFS of a quantum dot (QD) with broken inversion symmetry interacting with a plasmonic nanostructure. The QD is described as a two-level atom-like system with a permanent dipole moment in the excited state. A linearly polarized laser field drives the optical transition of the QD and produces localized surface plasmons in the MNP. The influence of plasmonic effects between the nanoparticle and the dot is analyzed using the Green tensor method. We found terahertz (THz) emission in the resonance fluorescence spectrum when the laser frequency lies above the transition frequency. The position and strength of the THz peaks is controlled by means of the dot-nanoparticle separation. The quantum nature of the emitted THz photons is analyzed by evaluating the second-order fluorescence intensity correlation function. We found a periodic alternation of photon bunching and anti-bunching with a period that depends on the polarization of the driving field.Item Phase shift of amplitude-modulated optical signals in graphene oxide water dispersions due to thermal lens focal length oscillation(Journal of the Optical Society of America B, 2014) Melle Hernández, Sonia; Gómez Calderón, Óscar; Egatz-Gómez, Ana; Cabrera Granado, Eduardo; Carreño Sánchez, Fernando; Salavagione, H. J.; Antón Revilla, Miguel ÁngelWe analyze the phase shift induced in an amplitude-modulated laser beam propagating through a water dispersion of graphene oxide sheets in a fiber-to-fiber U-bench. This phase shift arises from the thermally induced nonlinear refraction in the sample. The system exhibits strong optical limiting performance for weak continuous-wave signals. A theoretical model including beam propagation and thermal lens focal length oscillation reproduces the experimental findings.- Project number: 200
Item Desarrollo de herramientas interactivas con acceso remoto para el aprendizaje de óptica biomédica(2015) Cabrera Granado, Eduardo; Gómez Calderón, Óscar; Melle Hernández, Sonia; Antón Revilla, Miguel Ángel; Carreño Sánchez, Fernando; Díaz García, Elena; López Alonso, José Manuel; Arrieta Yañez, FranciscoNuevos documentos de trabajo y consulta basados en IPython Notebook han sido desarrollados con el fin de ofrecer nuevas herramientas para el aprendizaje de la asignatura de Óptica Biomédica de la Facultad de Óptica y Optometría. Este tipo de documentos permiten una mayor libertad al estudiante para explorar distintos temas de Óptica Biomédica facilitando su acceso remoto sin la necesidad de instalar software en su ordenador personal.