Person: Villaverde Cantizano, Gonzalo
Loading...
First Name
Gonzalo
Last Name
Villaverde Cantizano
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Farmacia
Department
Química en Ciencias Farmacéuticas
Area
Química Física
Identifiers
17 results
Search Results
Now showing 1 - 10 of 17
Item New chiral ligands bearing two N-heterocyclic carbene moieties at a dioxolane backbone. Gold, palladium and rhodium complexes as enantioselective catalysts(2010) Arnanz, Avelina ; González-Arellano, Camino ; Juan, Alberto; Villaverde Cantizano, Gonzalo; Corma, Avelino ; Iglesias, Marta ; Sánchez, FélixBiscarbene ligands with two imidazolin-2-ylidene moieties at a chiral dioxolane backbone were used as ligands for gold, rhodium and palladium complexes. All new complexes showed varying degrees of enantioselectivity toward hydrogenation of prochiral alkenes with ees up to 95%.Item Chiral NHC‐Complexes with Dioxolane Backbone Heterogenized on MCM‐41. Catalytic Activity(2011) Villaverde Cantizano, Gonzalo; Corma, Avelino ; Iglesias, Marta ; Sánchez, FélixRhodium, palladium, and gold complexes of chiral (NHC)–dioxolane–amino ligands were prepared. Herein, new methods for the heterogenization of NHC-chiral complexes on porous silica supports are demonstrated for the facile recovery and recycling of these expensive catalysts. Activity, selectivity, and recyclability were investigated and compared to that of the analogous homogeneous catalysts for asymmetric hydrogenation reactions. The compounds were characterized by using a variety of methods, including solid state cross-polarization magic-angle spinning (CP MAS) 13C NMR, FT-IR spectroscopy, and elemental analysis. Heterogenized rhodium(I) and palladium(II) catalysts could be used at least four times without loss of activity or enantioselectivity. (NHC)–gold(I) complexes were easily immobilized and recycled by a treatment with benzonitrile during the washing steps between cycles. This washing maintained the activity and enantioselectivity.Item A new targeting agent for the selective drug delivery of nanocarriers for treating neuroblastoma(2015) Villaverde Cantizano, Gonzalo; Baeza, Alejandro ; Melen, Gustavo J. ; Alfranc, Arantzazu ; Ramírez, Manuel ; Vallet Regí, María Dulce NombreNovel targeting agents against neuroblastoma based on the meta-iodobenzylguanidine (MIBG) moiety were synthesized and biologically evaluated for nanocarrier vectorization. These compounds have been anchored on the surface of drug loaded mesoporous silica nanocarriers, resulting in the improved cellular uptake in tumoral cells. Neuroblastoma (NB) is the most frequent extracranial pediatric tumor. Advanced forms of the disease (metastatic and/or refractory) have a dismal prognosis despite the combination of chemotherapy, radiotherapy, surgery and bone narrow transplants. These treatments carry severe side effects and, in some cases, compromise the life of the patient. MIBG has been widely applied in the medical diagnosis of NB due to its affinity for tumor cells through the norepinephrine transporter (NET), which is expressed in 90% of NB tumors. The exclusive accumulation of MIBG in neuroblastoma has been widely studied; however, its properties have been never exploited as a targeting agent in nanocarrier drug delivery systems. Several structural analogues of MIBG have been prepared and attached on the surface of nanocarriers. Their selective internalization has been tested against human neuroblastoma cells, which show, in the best case, cellular uptake four times higher than that of the naked nanosystem. Furthermore, in vivo experiments showed preferential and selective accumulation and retention of the targeted nanosystem comparing with the naked and only PEGylated counterpart systems. This novel nanosystem could be easily applicable to all kinds of drug delivery nanocarriers, providing a universal tool for neuroblastoma chemotherapies that is superior to classical approaches through a novel nanosystem exclusively designed to target this terrible malignancy.Item Controlling Size and Morphology in Hybrid Core@Shell and Core@Shell@Satellite Nanostructures for Sensing by Surface-Enhanced Raman Scattering(2020) Alarcón-Fernández, Carlos; Doña Flores, Manuel; Tapia-Fernández, Antonio; Villaverde Cantizano, Gonzalo; López-Ramírez, María Rosa; López-Moreno, Juan Manuel; Contreras-Cáceres, RafaelHere, we report the fabrication of several hybrid bimetallic core@shell and core@shell@satellite colloidal nanostructures. These nanosystems are structured as spherical and non-spherical metallic and bimetallic cores encapsulated by a thermo-responsive N-isopropylacrylamide (pNIPAM) shell (core@shell) with incorporated Ag satellites (core@shell@satellite). The metallic and bimetallic non-spherical cores include Au nanotriangles and bimetallic AuAg nanocubes, respectively. By using different amounts of AgNO3 during chemical reduction and through the seed-mediated approach, we are able to modify the Ag satellite sizes. We performed thermo-responsive surface-enhanced Raman spectroscopy (SERS) investigations for core@shell and core@shell@satellite nanosystems as a function of temperature, with improved SERS responses for the core@shell@satellite structure.Item Targeting strategies for improving the efficacy of nanomedicine in oncology(2019) Villaverde Cantizano, Gonzalo; Baeza García, AlejandroThe use of nanoparticles as drug carriers has provided a powerful weapon in the fight against cancer. These nanocarriers are able to transport drugs that exhibit very different nature such as lipophilic or hydrophilic drugs and big macromolecules as proteins or RNA. Moreover, the external surface of these carriers can be decorated with different moieties with high affinity for specific membrane receptors of the tumoral cells to direct their action specifically to the malignant cells. The selectivity improvement yielded by these nanocarriers provided a significative enhancement in the efficacy of the transported drug, while the apparition of side effects in the host was reduced. Additionally, it is possible to incorporate targeting moieties selective for organelles of the cell, which improves even more the effect of the transported agents. In the last years, more sophisticated strategies such as the use of switchable, hierarchical or double targeting strategies have been proposed for overcoming some of the limitations of conventional targeting strategies. In this review, recent advances in the development of targeted nanoparticles will be described with the aim to present the current state of the art of this technology and its huge potential in the oncological field.Item Double Sequential Encrypted Targeting Sequence: A New Concept for Bone Cancer Treatment(2017) Villaverde Cantizano, Gonzalo; Nairi, Valentina ; Baeza, Alejandro ; Vallet Regí, María Dulce NombreThe selective transportation of therapeutic agents to tumoral cells is usually achieved by their conjugation with targeting moieties able to recognize these cells. Unfortunately, simple and static targeting systems usually show a lack in selectivity. Herein, a double sequential encrypted targeting system is proposed as a stimuli-responsive targeting analogue for selectivity enhancement. The system is able to recognize diseased bone tissue in the first place, and once there, a hidden secondary targeting group is activated by the presence of an enzyme overproduced in the malignant tissue (cathepsin K), thereby triggering the recognition of diseased cells. Transporting the cell targeting agent in a hidden conformation that contains a high selective tissular primary targeting, could avoid not only its binding to similar cell receptors but also the apparition of the binding-site barrier effect, which can enhance the penetration of the therapeutic agent within the affected zone. This strategy could be applied not only to conjugate drugs but also to drug-loaded nanocarriers to improve the efficiency for bone cancer treatments.Item 10-Fold Quantum Yield Improvement of Ag2S Nanoparticles by Fine Compositional Tuning(ACS Applied materials and interfaces, 2020) Ortega Rodríguez, Alicia; Shen, Yingli; Zabala Gutiérrez, Irene; Santos, Harrison D. A.; Torres Vera, Vivian Andrea; Ximedes, Erving; Villaverde Cantizano, Gonzalo; Lifante, José; Gerke, Christoph; Fernández Monsalve, Nuria; Gómez Calderón, Óscar; Melle Hernández, Sonia; Marqués Hueso, José; Méndez González, Diego; Laurenti, Marco; Jones, Callum M. S.; López Romero, Juan Manuel; Contreras Cáceres, Rafael; Jaque García, Daniel; Rubio Retama, Benito Jorge; Garma Pons, SantiagoAg2S semiconductor nanoparticles (NPs) are near-infrared luminescent probes with outstanding properties (good biocompatibility, optimum spectral operation range, and easy biofunctionalization) that make them ideal probes for in vivo imaging. Ag2S NPs have, indeed, made possible amazing challenges including in vivo brain imaging and advanced diagnosis of the cardiovascular system. Despite the continuous redesign of synthesis routes, the emission quantum yield (QY) of Ag2S NPs is typically below 0.2%. This leads to a low luminescent brightness that avoids their translation into the clinics. In this work, an innovative synthetic methodology that permits a 10-fold increment in the absolute QY from 0.2 up to 2.3% is presented. Such an increment in the QY is accompanied by an enlargement of photoluminescence lifetimes from 184 to 1200 ns. The optimized synthetic route presented here is based on a fine control over both the Ag core and the Ag/S ratio within the NPs. Such control reduces the density of structural defects and decreases the nonradiative pathways. In addition, we demonstrate that the superior performance of the Ag2S NPs allows for high-contrast in vivo bioimaging. .Item Double sequential encrypted targeting sequence: A new concept for bone cancer treatment(Chemistry: a european journal, 2017) Villaverde Cantizano, Gonzalo; Nairi, Valentina; Baeza, Alejandro; Vallet Regí, María Dulce NombreThe selective transportation of therapeutic agents to tumoral cells is usually achieved by their conjugation with targeting moieties able to recognize these cells. Unfortunately, simple and static targeting systems usually show selectivity lacks. Herein, double sequential encrypted targeting system is proposed as stimuliresponsive targeting analogue for selectivity enhancement. The system is able to recognize diseased bone tissue in first place, and once there, a hidden secondary targeting group is activated by the presence of an enzyme overproduced in the malignant tissue (cathepsin K), triggering the recognition of diseased cells. Transporting the cell targeting agent in a hidden conformation which contains a high selective tissular primary targeting, could avoid not only its binding to similar cell receptors but also the apparition of the binding-site barrier effect, which can enhance the penetration of the therapeutic agent within the affected zone. This strategy could be applied not only to conjugate drugs but also to drug loaded nanocarriers in order to improve the efficiency for bone cancer treatments.Item Targeted Chemo‐Photothermal Therapy: A Nanomedicine Approximation to Selective Melanoma Treatment(2018) Villaverde Cantizano, Gonzalo; Gómez Graña, Sergio; Guisasola, Eduardo ; García García, María Isabel; Hanske, Christoph ; Liz‐Marzán, Luis M. ; Baeza, Alejandro ; Vallet Regí, María Dulce NombreMelanoma is one of the most severe public health issues worldwide, not only because of the high number of cases but also for its poor prognosis in late stages. Therefore, early diagnosis and efficient treatment are key toward a future solution. However, melanoma is highly resistant to cytotoxicity in its metastatic form. In this context, a therapeutic strategy based on a targeted chemo-photothermal nanotransporter for cytotoxic compounds is proposed. This approach comprises the use of core–multishell gold nanorods, coated with mesoporous silica and further covered with a thermosensitive polymer, which is vectorized for selective internalization in melanoma cells. The proposed nanoformulation is capable of releasing the transported cytotoxic compounds on demand, in response to near-IR irradiation, with high selectivity and efficacy against malignant cells, even at low concentrations, thereby providing a new tool against melanoma disease.Item SPION nanoparticles for delivery of dopaminergic isoquinoline and benzazepine derivatives(Bioorganic & Medicinal Chemistry, 2022) Lucena-Serrano, Cristina; Lucena-Serrano, Ana; Díaz, Amelia; Valpuesta, María; Villaverde Cantizano, Gonzalo; López-Romero, J. Manuel; Sarabia, Francisco; Laurenti, Marco; Rubio Retama, Benito Jorge; Contreras Cáceres, RafaelSuperparamagnetic iron nanoparticles (SPIONs) have become one of the most useful colloidal systems in nanomedicine. We report here the preparation of new hybrid core@shell systems based on SPION nanoparticles coated with a SiO2 shell (SPION@SiO2) and functionalized with carboxyl groups SPION@SiO2-COOH). A series of new N-alkylamino- and N-alkylamido-terminated 1-phenyl- tetrahydroisoquinolines (THIQs) and 3 tetrahydrobenzazepines (THBs) derivatives presenting -SMe and -Cl groups, respectively, with potential dopaminergic activity, are synthesized and incorporated to the hybrid system. We include the synthetic details for THIQs and THBs derivatives preparation and investigate the influence of the terminal-functional group as well as the number of carbon atoms linked to THIQ and THB molecules during the coupling to the SPION@SiO2-COOH. Nuclear magnetic resonance (NMR) and electron ionization mass spectrometry (EI-MS) are used to characterize the synthesized THIQs and THBs. High-angle annular dark-field transmission electron microscopy (HAADFTEM), energy dispersive X-ray transmission electron microscopy (EDX-TEM), and proton high-resolution magic angle spinning NMR spectroscopy1 H HRMAS-NMR) are used to confirm the presence of THB and THIQ molecules onto the surface of the nanoparticles. The hybrid SPION@SiO2-THIQ and THB systems show significant activity toward the D2 receptor, reaching Ki values of about 20 nM, thus having potential application in the treatment of central nervous system (CNS) diseases.