Person: García Fresnadillo, David
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First Name
David
Last Name
García Fresnadillo
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Orgánica
Area
Química Orgánica
Identifiers
7 results
Search Results
Now showing 1 - 7 of 7
- Project number: 166
Item Determinantes del bajo rendimiento académico universitario: análisis del impacto de las variables previas al acceso a la universidad(2022) García Fresnadillo, David; Constante Amores, Israel Alexander; Cuervo Rodríguez, María Rocío; Martínez Sánchez, Juan Carlos; Moreno Jiménez, Florencio; Ramírez Castellanos, JulioMejora del rendimiento académico en la asignatura Química de 1º de Grado en Química, Ing. Química, Optometría y Biología. Enfoque preventivo y diagnóstico. Análisis de factores (sociodemográficos, académicos y uso de TIC) al inicio de 1º curso. - Project number: 365
Item Influencia del cambio en la metodología de enseñanza-aprendizaje y de evaluación, de presencial a on-line, en el aprendizaje de contenidos, competencias y en el rendimiento académico de estudiantes de primer curso de grado de la UCM(2021) García Fresnadillo, David; Cuervo Rodríguez, María Rocío; Moreno Jiménez, Florencio; Ramírez Castellanos, Julio; Arrieta Dillon, Marina Patricia; Constante Amores, Israel Alexander; Martínez Sánchez, Juan CarlosDebido a Covid-19, el cambio en el modo de enseñar y evaluar al alumnado, con más énfasis en el campus virtual, afectará sensiblemente al curso 2020-2021. Se analiza la influencia sobre el aprendizaje y rendimiento académico de la asignatura Química en los estudiantes de 1º curso de varios grados de ciencias de la UCM. Item An Ultra‐Long‐Lived Triplet Excited State in Water at Room Temperature: Insights on the Molecular Design of Tridecafullerenes(Angewandte Chemie International Edition, 2021) Ramos Soriano, Javier; Pérez Sánchez, Alfonso; Ramírez Barroso, Sergio; Illescas, Beatriz M.; Azmani, Khalid; Rodríguez Fortea, Antonio; Poblet, Josep M.; Hally, Cormac; Nonell, Santi; García Fresnadillo, David; Rojo, Javier; Martín León, NazarioSuitably engineered molecular systems exhibiting triplet excited states with very long lifetimes are important for high-end applications in nonlinear optics, photocatalysis, or biomedicine. We report the finding of an ultra-long-lived triplet state with a mean lifetime of 93 ms in an aqueous phase at room temperature, measured for a globular tridecafullerene with a highly compact glycodendrimeric structure. A series of three tridecafullerenes bearing different glycodendrons and spacers to the C60 units have been synthesized and characterized. UV/Vis spectra and DLS experiments confirm their aggregation in water. Steady-state and time-resolved fluorescence experiments suggest a different degree of inner solvation of the multifullerenes depending on their molecular design. Efficient quenching of the triplet states by O2 but not by waterborne azide anions has been observed. Molecular modelling reveals dissimilar access of the aqueous phase to the internal structure of the tridecafullerenes, differently shielded by the glycodendrimeric shell.Item Exploring BODIPY Derivatives as Singlet Oxygen Photosensitizers for PDT(Photochemistry and Photobiology, 2020) Prieto Moreno, Ruth; Prieto Castañeda, Alejandro; Sola Llano, Rebeca; Rodríguez Agarrabeitia, Antonia; García Fresnadillo, David; López Arbeloa, Íñigo María; Villanueva Oroquieta, Ángeles; Ortíz García, María Josefa; Moya Cerero, Santiago de la; Martínez Martínez, VirginiaThis minireview is devoted to honoring the memory of Dr. Thomas Dougherty, a pioneer of modern photodynamic therapy (PDT). It compiles the most important inputs made by our research group since 2012 in the development of new photosensitizers based on BODIPY chromophore which, thanks to the rich BODIPY chemistry, allows a finely tuned design of the photophysical properties of this family of dyes to serve as efficient photosensitizers for the generation of singlet oxygen. These two factors, photophysical tuning and workable chemistry, have turned BODIPY chromophore as one of the most promising dyes for the development of improved photosensitizers for PDT. In this line, this minireview is mainly related to the establishment of chemical methods and structural designs for enabling efficient singlet oxygen generation in BODIPYs. The approaches include the incorporation of heavy atoms, such as halogens (iodine or bromine) in different number and positions on the BODIPY scaffold, and also transition metal atoms, by their complexation with Ir(III) center, for instance. On the other hand, low‐toxicity approaches, without involving heavy metals, have been developed by preparing several orthogonal BODIPY dimers with different substitution patterns. The advantages and drawbacks of all these diverse molecular designs based on BODIPY structural framework are described.- Project number: 30
Item Mentoría y aprendizaje significativo enfocado en estudiantes de primer curso de universidad: necesidades, expectativas y logros(2021) Cuervo Rodríguez, María Rocío; García Fresnadillo, David; Moreno Jiménez, Florencio; Ramírez Castellanos, Julio; García Pereira, Francisco Javier; Martínez Sánchez, Juan Carlos; Arrieta Dillon, Marina Patricia; Schad Alburquerque, Cristobal Martín Item 'Desde el aprobado al no presentado. ¿Cuáles son las causas del abandono de una asignatura? Análisis de la asignatura Química de primer curso de grado en facultades de ciencias'(2023) García Fresnadillo, David; Cuervo Rodríguez, María Rocío; Moreno Jiménez, Florencio; Ramírez Castellanos, Julio; Yang, Fan; Martínez Sánchez, Juan Carlos; Ribeiro González, Antonio; Agudo Blanco, Carlos; García Fresnadillo, DavidLa universidad española presenta un elevado porcentaje de estudiantes que abandonan la titulación que están cursando, o que muestran muy bajo rendimiento académico durante el primer curso de grado. Entre estos estudiantes hay que destacar un significativo número de estudiantes que abandonan ciertas asignaturas durante el curso académico, no presentándose a los exámenes finales (ordinario y extraordinario) de las mismas. El objetivo general del proyecto se centra en el estudio y análisis de los factores que, en el momento de entrada en la Universidad, están asociados al abandono de la asignatura de Química, con el propósito de llevar a cabo el diseño de un conjunto de acciones formativas destinadas a los estudiantes del primer curso del Grado en Óptica y Optometría, Grado en Ingeniería Química, Grado en Biología y Grado en Química, persiguiendo reducir la alta tasa de abandono de esta asignatura. Hay que tener presente que este trabajo se propone analizar las variables previas al acceso a la universidad, puesto que, únicamente de esta manera, se puede llevar a cabo un enfoque preventivo y diagnóstico.Item An integrated photosensitizing/adsorbent material for the removal of triclosan from water samples(Separation and Purification Technology, 2020) Marazuela Lamata, María Dolores; García Fresnadillo, DavidTriclosan, a recalcitrant micropollutant linked to antimicrobial resistance, is not completely eliminated during wastewater treatment, reason why it has become ubiquitous, causing serious environmental problems. Photocatalytic removal of triclosan has been investigated using sunlight and a composite material consisting of tris(4,7-diphenyl-1,10 phenanthroline)ruthenium(II) chloride [Ru(dip)3]Cl2 –a singlet oxygen (1O2) photosensitizer– immobilized on poly-dimethylsiloxane (PDMS) membranes. The efficiency of triclosan photodegradation has been evaluated, as well as the influence of variables such as pH, water matrix composition and triclosan adsorption on the material. The sunlight-driven process led to an effective decrease in triclosan concentration (C0 as high as 0.35 or 1.5 mg L−1 in ultra-pure and natural water samples, respectively), with removal rates > 80% within 30 min in the presence of the photosensitizing material, while it was ≤ 50% in direct photolysis tests in the absence of the material. The improved efficiency of triclosan removal with the photosensitizing material is even more effective with the phenolic form of triclosan, which may be attributed to synergistic adsorption of the pollutant on the polymer matrix and subsequent photodegradation by 1O2. Direct photolysis is, however, the dominant pathway for the depletion of the phenolate form, although the reaction with 1O2 always increases the removal rates of the deprotonated triclosan, due to the strong electrophilic nature of this reactive oxygen species. LC-QTOF-MS screening of treated water samples did not show the presence of ions characteristic of already reported toxic triclosan phototransformation products (e.g. dioxins, dichlorophenols, etc). Moreover, these photosensitizing/adsorbent materials can be easily incorporated into solar photoreactors, allowing simple separation of the treated water. Therefore, these integrated photosensitizing/adsorbent materials may offer novel green and cost-effective options for sustainable treatment of polluted waters.