Person:
Laurenti, Marco

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First Name
Marco
Last Name
Laurenti
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Farmacia
Department
Química en Ciencias Farmacéuticas
Area
Química Física
Identifiers
UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet IDGoogle Scholar ID

Search Results

Now showing 1 - 10 of 15
  • Publication
    Oligonucleotide Sensor Based on Selective Capture of Upconversion Nanoparticles Triggered by Target Induced DNA Inter-Strand Ligand Reaction
    (Amer Chemical Soc., 2017-03-23) 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, Jorge
    We 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.
  • Publication
    Jugando con métodos interactivos para incentivar el aprendizaje de la física y fisicoquímica
    (2023-07-28) Marciello, Marzia; Alvear Jiménez, Alexis Fernando; Contreras Cáceres, Rafael; Díaz García, Diana; Fernández Fernández, María de la Cabeza; Filice, Marco; García Almodóvar, Victoria; Gómez Ruiz, Santiago; Laurenti, Marco; Lozano Chamizo, Laura; Méndez Gonzalez, Diego; Ovejero Paredes, Karina; Sanchez Sanchez, Visitación
    La sociedad actual se presenta cada día más tecnificada y los estudiantes están creciendo en ella desarrollando distintas capacidades cognitivas que resultan casi imprescindible comprender y atender para poder aumentar su interés en el aprendizaje de diferentes temas. Esta realidad está llevando los profesores a reconfigurar sus estrategias pedagógicas, actualizando los métodos educativos con el fin de mejorar la calidad de la educación adaptando los contenidos que se imparten con las necesidades de la sociedad. Por ello, cada vez es más frecuente recurrir a nuevas herramientas como las TIC (Tecnologías de la Información y las Comunicaciones) y a aplicaciones lúdicas que apoyen y fomenten el proceso de aprendizaje. La aplicación de las TICs en la enseñanza, ha supuesto un avance en la transmisión y recepción del conocimiento para incentivar a los alumnos al aprendizaje de aquellas asignaturas que suponen una mayor dificultad durante su proceso formativo. Asimismo, la gamificación, que consiste en incorporar elementos de juegos como las recompensas y la competición para animar a las estudiantes a realizar tareas que normalmente se consideran aburridas, está ganando cada día más atención sobre todo gracias a su innegable carácter motivacional. De hecho, el juego es un activador en la atención y surge como alternativa para complementar los esquemas de la enseñanza tradicional. Debido a su naturaleza intrínseca, el aprendizaje de la física y de la fisicoquímica (tanto en campo farmacéutico como en general) suele resultar un proceso complicado y muchas veces difícil de entender. Los métodos tradicionales de enseñanza de la ciencia en general, y de la física y fisicoquímica en particular, hacen que estas disciplinas fundamentales sean vistas por los alumnos como algo abstracto y poco estimulante. El objetivo de la actividad propuesta en este proyecto es convertir el estudio de dichas materias en algo más interesante y participativo, motivando a los estudiantes mediante juegos basados en herramientas TIC y generando finalmente un mejor conocimiento gracias a la competición lúdica, al aprendizaje colaborativo y a la autoevaluación. En este sentido, nuestra propuesta se ha centrado en actividades interactivas basadas en la gamificación para el desarrollo de un aprendizaje proactivo de asignaturas complejas permitiendo al mismo tiempo una autoevaluación tanto a los estudiantes como a los profesores. De hecho, los alumnos, gracias a la resolución de preguntas en forma de juego han podido valorar su nivel de aprendizaje durante el desarrollo del curso y el profesor ha podido comprobar si sus clases son los suficientemente claras y/o cuales argumentos debería de profundizar y/o explicar de otra manera para obtener una mayor comprensión por parte de los estudiantes.
  • Publication
    Control of upconversion luminescence by gold nanoparticle size: from quenching to enhancement
    (RSC, 2019-08-07) 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, Elena
    Metallic 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.
  • Publication
    Ultrafast photochemistry produces superbright short-wave infrared dots for low-dose in vivo imaging
    (Nature Publishing Group, 2020-06-10) Santos, Harrison D. A.; Zabala Gutiérrez, Irene; Shen, Yingli; Lifante, José; Ximendes, Erving; Laurenti, Marco; Méndez González, Diego; Melle Hernández, Sonia; Gómez Calderón, Óscar; López Cabarcos, Enrique; Fernández Monsalve, Nuria; Chavez Coria, Irene; Lucena Agell, Daniel; Monge, Luis; Mackenzie, Mark D.; Marqués Hueso, José; Jones, Callum M. S.; Jacinto, Carlos; Rosal, Blanca, del; Kar, Ajoy K.; Rubio Retama, Jorge; Jaque García, Daniel
    Optical probes operating in the second near-infrared window (NIR-II, 1,000-1,700 nm), where tissues are highly transparent, have expanded the applicability of fluorescence in the biomedical field. NIR-II fluorescence enables deep-tissue imaging with micrometric resolution in animal models, but is limited by the low brightness of NIR-II probes, which prevents imaging at low excitation intensities and fluorophore concentrations. Here, we present a new generation of probes (Ag2S superdots) derived from chemically synthesized Ag2S dots, on which a protective shell is grown by femtosecond laser irradiation. This shell reduces the structural defects, causing an 80-fold enhancement of the quantum yield. PEGylated Ag2S superdots enable deep-tissue in vivo imaging at low excitation intensities (<10 mW cm−2) and doses (<0.5 mg kg−1), emerging as unrivaled contrast agents for NIR-II preclinical bioimaging. These results establish an approach for developing superbright NIR-II contrast agents based on the synergy between chemical synthesis and ultrafast laser processing.
  • Publication
    Las TICs: un instrumento de ayuda en las prácticas de laboratorio
    (2022-01-31) Laurenti, Marco; Ovejero Paredes, Karina; Zabala Gutiérrez, Irene; Sanchez Sanche, Visitación; Yusta San Roman, Piedad; Contreras Cáceres, Rafael; Filice, Marco; López Cabarcos, Enrique; Marciello, Marzia; Méndez González, Diego; Rubio Retama, Benito Jorge; Villaverde Cantizano, Gonzalo
    Desde la implantación del Espacio Europeo de Educación Superior nos encontramos ante dos grandes retos; el desarrollo metodológico y tecnológico en la formación y docencia on-line y en segundo lugar la cada vez más elevada especialización requerida a los estudiantes durante el Grado y Doble Grado en Farmacia. Esto hace que el foco de la formación de los estudiantes se desvíe de los conocimientos básicos y competencias de formación tanto en el trabajo experimental como en el conocimiento teórico. El proyecto se encuadra en el marco de la asignatura obligatoria Física Aplicada a Farmacia de Grado y Doble Grado en Farmacia, unas carreras con una elevada carga práctica y experimental.
  • Publication
    FRET distance dependence from upconverting nanoparticles to quantum dots
    (Amer Chemical Soc, 2018-05) 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, Jorge
    Förster 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.
  • Publication
    Oligonucleotide sensor based on magnetic capture and photoligation of upconverting nanoparticles in solid surfaces
    (Elsevier, 2021-03-11) Méndez González, Diego; Silva Ibáñez, Pedro Pablo; Valiente Dies, Fernando; Gómez Calderón, Óscar; Mendez González, Juan Luis; Laurenti, Marco; Egatz-Gómez, Ana; Díaz García, Elena; Rubio Retama, Jorge; Melle Hernández, Sonia
    In this work, we present a luminescence platform that can be used as point of care system for determining the presence and concentration of specific oligonucleotide sequences. This sensor exhibited a limit of detection as low as 50 fM by means of: i) the use of single-stranded DNA (ssDNA) functionalized magnetic microparticles that captured and concentrated ssDNA-upconverting nanoparticles (ssDNA-UCNPs) on a solid support, when the target sequence (miR-21-5p DNA-analogue) was in the sample, and ii) a photoligation reaction that covalently linked the ssDNA-UCNPs and the ssDNA magnetic microparticles, allowing stringent washes. The presented sensor showed a similar limit of detection when the assays were conducted in samples containing total miRNA extracted from human serum, demonstrating its suitability for detecting small specific oligonucleotide sequences under real-like conditions. The strategy of combining UCNPs, magnetic microparticles, and photoligation reaction provides new insight into low-cost, rapid, and ultra-sensitive detection of oligonucleotide sequences.
  • Publication
    Zinc oxide nanocrystals as nano-antibiotic and osteoinductive agents
    (Royal Society of Chemistry, 2019-01) Garino, Nadia; Sanvitale, Pasquale; Dumontel, Bianca; Laurenti, Marco; Colilla, Montserrat; Izquierdo-Barba, Isabel; Cauda, Valentina; Vallet Regí, María
    The use of nanomaterials in the field of bone tissue engineering implants is continuously dealing with the development of innovative solutions to common problems, as infection by colonization with common microbial agents, antibiotic bacterial resistance, and the formation of new bone tissue. Among them, ZnO nanostructures are promising candidates thanks to their intrinsic antimicrobial activity and high biocompatibility. In this paper we aim to analyse the behaviour of ZnO nanocrystals (ZnO NCs), prepared with a new synthetic approach and not embedded in any composite matrix, for bone implants applications in-vitro. In particular, we have developed a novel, fast and reproducible microwave-assisted synthesis, obtaining highly-crystalline, round-shaped ZnO NCs of 20 nm in diameter as an extremely-stable colloidal solution in ethanol. Part of them were also chemically functionalized by anchoring amino-propyl groups to the ZnO surface (ZnO-NH2 NCs). Thus, the role of both ZnO NCs concentration and surface chemistry are tested in terms of biocompatibility towards pre-osteoblasts cells, promotion of cell proliferation and differentiation, and also in terms of antimicrobial activity against Gram positive and negative bacteria, such as Escherichia coli and Staphylococcus aureus, respectively. The results propose the ZnO-NH2 NCs as the most promising candidate to solve infections disease in bone implants and promote bone tissue proliferation at the same time, even at high concentrations. Whereas further investigations are needed for example to clarify the mechanism inhibiting biofilm formation and to investigate their role in in-vivo assays, we demonstrated that a fine and reproducible control over the chemical and structural parameters in ZnO nanomaterials can open new horizons in the use of functionalized ZnO NCs as a highly biocompatible and osteoinductive nanoantibiotic agent for bone tissue engineering.
  • Publication
    The effects of dopant concentration and excitation intensity on the upconversion and downconversion emission processes of β-NaYF4:Yb3+,Er3+nanoparticles
    (Royal Soc. Chemistry, 2021-06-04) Torres Vera, Vivian; Méndez González, Diego; Ramos Ramos, D.J.; Igalla El Youssfi, Asmae; Laurenti, Marco; Contreras Cáceres, Rafael; López Cabarcos, Enrique; Díaz García, Elena; Rubio Retama, Jorge; Melle Hernández, Sonia; Gómez Calderón, Oscar
    The dopant concentration of lanthanide ions in photon upconversion nanoparticles (UCNPs) remains one of the key points to boost the brightness of these nanomaterials and, therefore, their application developments. Here, we analyzed the effect of Er3+ and Yb3+ dopant concentrations of b-NaYF4:Yb3+,Er3+ nanoparticles on the visible upconversion and near-infrared downconversion luminescence intensities. Our approach carefully excluded all other factors whose variation affects luminescence properties such as the size, morphology, crystal structure, ion distribution, ligand, and surrounding medium, allowing us to exactly infer the influence of the ratio of Yb3+ to Er3+ ions on the nanoparticle luminescence. To maintain the size and morphological properties of nanoparticles, we used a total dopant concentration of 22% while varying the ratio of Yb3+ to Er3+ ions from 0 to 10. A huge increase in luminescence takes place as the Yb/Er ratio increases following a power-law behavior, and this luminescence enhancement is greater at low excitation intensities. Above a Yb/Er ratio of around two, saturation occurs with a slight peak when this ratio is around four. Simulations using a rate equation model showed that upconversion luminescence (UCL) is mainly produced by the energy transfer between neighboring Er3+ ions at low Yb/Er ratios, while at high ratios, the energy transfer from Yb3+ to Er3+ ions dominates. However, downconversion luminescence (DCL) is produced at all analyzed ratios, except 0, by the previous mechanism.
  • Publication
    Upconverting Nanoparticles in Aqueous Media: Not a Dead-End Road. Avoiding Degradation by Using Hydrophobic Polymer Shells
    (Wiley, 2021-12-13) Méndez González, Diego; Torres Vera, Vivian Andrea; Zabala Gutiérrez, Irene; Gerke, Christoph; Cascales Sedano, Concepción; Rubio Retama, Jorge; Gómez Calderón, Óscar; Melle Hernández, Sonia; Laurenti, Marco
    The stunning optical properties of upconverting nanoparticles (UCNPs) have inspired promising biomedical technologies. Nevertheless, their transfer to aqueous media is often accompanied by intense luminescence quenching, partial dissolution by water, and even complete degradation by molecules such as phosphates. Currently, these are major issues hampering the translation of UCNPs to the clinic. In this work, a strategy is developed to coat and protect β-NaYF4 UCNPs against these effects, by growing a hydrophobic polymer shell (HPS) through miniemulsion polymerization of styrene (St), or St and methyl methacrylate mixtures. This allows one to obtain single core@shell UCNPs@HPS with a final diameter of ≈60–70 nm. Stability studies reveal that these HPSs serve as a very effective barrier, impeding polar molecules to affect UCNPs optical properties. Even more, it allows UCNPs to withstand aggressive conditions such as high dilutions (5 μg mL−1), high phosphate concentrations (100 mm), and high temperatures (70 °C). The physicochemical characterizations prove the potential of HPSs to overcome the current limitations of UCNPs. This strategy, which can be applied to other nanomaterials with similar limitations, paves the way toward more stable and reliable UCNPs with applications in life sciences.