Person: Vallet Regí, María Dulce Nombre
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First Name
María Dulce Nombre
Last Name
Vallet Regí
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Farmacia
Department
Química en Ciencias Farmacéuticas
Area
Química Inorgánica
Identifiers
37 results
Search Results
Now showing 1 - 10 of 37
Item Preventing bacterial adhesion on scaffolds for bone tissue engineering(International Journal of Bioprinting, 2016) Sánchez Salcedo, Sandra; Colilla Nieto, Montserrat; Izquierdo Barba, Isabel; Vallet Regí, María Dulce NombreBone implant infection constitutes a major sanitary concern which is associated to high morbidity and health costs. This manuscript focused on overviewing the main research efforts committed up to date to develop innovative alternatives to conventional treatments, such as those with antibiotics. These strategies mainly rely on chemical modifi-cations of the surface of biomaterials, such as providing it of zwitterionic nature, and tailoring the nanostructure surface of metal implants. These surface modifications have successfully allowed inhibition of bacterial adhesion, which is the first step to implant infection, and preventing long-term biofilm formation compared to pristine materials. These strate-gies could be easily applied to provide three-dimensional (3D) scaffolds based on bioceramics and metals, of which its manufacture using rapid prototyping techniques was reviewed. This opens the gates for the design and development of advanced 3D scaffolds for bone tissue engineering to prevent bone implant infections. Keywords: Antibacterial adhesion, biofilm formation, zwitterionic surfaces, nanostructured surfaces, rapid prototyping 3D scaffolds, bone tissue engineering.Item From Proof-of-Concept Material to PEGylated and Modularly Targeted Ultrasound-Responsive Mesoporous Silica Nanoparticles(Journal of Materials Chemistry B, 2018) Paris, J.L.; Villaverde, Gonzalo; Cabañas Criado, María Victoria; Manzano García, Miguel; Vallet Regí, María Dulce NombreIn this work we present the synthesis, characterization and in vitro biological evaluation of PEGylated and actively-targeted ultrasound-responsive hybrid mesoporous silica nanoparticles. This work covers the development of the chemical strategies necessary to afford a modular nanocarrier starting from a proof-of-concept material presented in previous work. This functional ultrasound-responsive material can be adapted to different specific pathological conditions by carefully choosing the appropriate targeting moieties. The new ultrasound responsive material is able to target HeLa cells when conjugated with biotin or an RGD peptide. Ultrasound-responsive cytotoxicity towards cancer cells of doxorubicinloaded nanoparticles is demonstrated in an in vitro cytotoxicity assay.Item Decidua-derived mesenchymal stem cells as carriers of mesoporous silica nanoparticles. In vitro and in vivo evaluation on mammary tumors(Acta Biomaterialia, 2016) Paris, Juan L.; Torre, Paz de la; Manzano, Miguel; Cabañas Criado, María Victoria; Flores, Ana I.; Vallet Regí, María Dulce NombreThe potential use of human Decidua-derived mesenchymal stem cells (DMSCs) as a platform to carry mesoporous silica nanoparticles in cancer therapy has been investigated. Two types of nanoparticles were evaluated. The nanoparticles showed negligible toxicity to the cells, a fast uptake and a long retention inside them. Nanoparticle location in the cell was studied by colocalization with the lysosomes. Moreover, the in vitro and in vivo migration of DMSCs towards tumors was not modified by the evaluated nanoparticles. Finally, DMSCs transporting doxorubicin-loaded nanoparticles were capable of inducing cancer cell death in vitro.Item Reversible nanogate system for Mesoporous Silica Nanoparticles based on Diels-Alder adducts.(Chemistry - A European Journal, 2018) Castillo Romero, Rafael; Hernández-Escobar, David; Gómez Graña, Sergio; Vallet Regí, María Dulce NombreThe implementation of nanoparticles as nanomedicines require from sophisticated surface modifications in order to reduce immune response and enhance recognition abilities. In addition to that, Mesoporous Silica nanoparticles present extraordinary host-guest abilities and facile surface functionalization. These two factors make them ideal candidates for the development of novel drug delivery systems, at the expense of increasing the structural complexity. With this idea in mind, a system of triggerable and tunable silica nanoparticles was developed for its application as drug delivery nanocarriers. For that purpose, Diels-Alder cycloaddition adducts were chosen as thermalresponsive units; that permitted to bind Au nanocaps able to block the pores and allow the incorporation of targeting fragments. The capping efficiency was tested under different thermal conditions, obtaining outstanding efficiencies within the physiological range and mild temperatures, as well as enhanced releases under pulsing heating cycles which showed the best release profiles.Item Assembly of Multicomponent Nano-Bioconjugates Composed of Mesoporous Silica Nanoparticles, Proteins, and Gold Nanoparticles(ACS Omega, 2019) Delpiano, Giulia; Casula, Maria; Piludu, Marco; Corpino, Riccardo; Ricci, Pier Carlo; Vallet Regí, María Dulce Nombre; Sanjust, Enrico; Monduzzi, Maura; Salis, AndreaThe purpose of this work was the assembly of multicomponent nano-bioconjugates based on mesoporous silica nanoparticles (MSNs), proteins (bovine serum albumin, BSA, or lysozyme, LYZ), and gold nanoparticles (GNPs). These nanobioconjugates may find applications in nanomedicine as theranostic devices. Indeed, MSNs can act as drug carriers, proteins stabilize MSNs within the bloodstream, or may have therapeutic or targeting functions. Finally, GNPs can either be used as contrast agents for imaging or for photothermal therapy. Here, amino-functionalized MSNs (MSN−NH2) were synthesized and characterized through various techniques (small angle X-rays scattering TEM, N2 adsorption/desorption isotherms, and thermogravimetric analysis (TGA)). BSA or lysozyme were then grafted on the external surface of MSN−NH2 to obtain MSN−BSA and MSN−LYZ bioconjugates, respectively. Protein immobilization on MSNs surface was confirmed by Fourier transform infrared spectroscopy, ζ-potential measurements, and TGA, which also allowed the estimation of protein loading. The MSN−protein samples were then dispersed in a GNP solution to obtain MSN−protein−GNPs nano-bioconjugates. Transmission electron microscopy (TEM) analysis showed the occurrence of GNPs on the MSN−protein surface, whereas almost no GNPs occurred in the protein-free control samples. Fluorescence and Raman spectroscopies suggested that proteins−GNP interactions involve tryptophan residues.Item Molecular gates in mesoporous bioactive glasses for the treatment of bone tumors and infection(Acta Biomaterialia, 2016) Polo, Lorena; Gómez Cerezo, María Natividad; Vivancos, Jose Luis; Sancenón, Félix; Arcos Navarrete, Daniel; Vallet Regí, María Dulce Nombre; Martínez Máñez, RamónSilica mesoporous nanomaterials have been proved to have meaningful application in biotechnology and biomedicine. Particularly, mesoporous bioactive glasses are recently gaining importance thanks to their bone regenerative properties. Moreover, the mesoporous nature of these materials makes them suitable for drug delivery applications, opening new lines in the field of bone therapies. In this work, we have developed innovative nanodevices based on the implementation of adenosine triphosphate (ATP) and e-poly-l-lysine molecular gates using a mesoporous bioglass as an inorganic support. The systems have been previously proved to work properly with a fluorescence probe and subsequently with an antibiotic(levofloxacin) and an antitumoral drug(doxorubicin). The bioactivity of the prepared materials has also been tested, giving promising results. Finally, in vitro cell culture studies have been carried out; demonstrating that this gated devices can provide useful approaches for bone cancer and bone infection treatments. Statement of Significance Molecular-gated materials have recently been drawing attention due to their applications in fields as biomedicine and molecular recognition. For the first time as we are aware, we report herein a new enzymatic responsive molecular-gated device consisting in a mesoporous bioactive glass support implemented with two different molecular gates. Both controlled drug delivery properties and apatite-like phase formation ability of the device have been demonstrated, getting promising results. This approach opens up the possibility of developing new stimuli-responsive tailored biomaterials for bone cancer and infection treatments as well as regenerative bone grafts.Item Heating at the Nanoscale through Drug-Delivery Devices: Fabrication and Synergic Effects in Cancer Treatment with Nanoparticles(Small Methods, 2018) Guisasola, Eduardo; Baeza, Alejandro; Asin, Laura; De la Fuente, J. M.; Vallet Regí, María Dulce NombreNanocarriers for cancer therapy have been extensively studied, but there is still some research that must be addressed in order to achieve their safe application. In this field, hyperthermia thermal treatments mediated by the us of responsive nanomaterials are not different, and researchers have carried out many attempts to overcome their drawbacks due to the valuable potential of these techniques. Here, an overview is presented of nanodevices based on magnetic- and photoresponsive nanocrystals that respond to magnetic fields and/or near-infrared stimuli for cancer therapies. Special attention is given to the synergic effect that can be achieved with nanoscale heating in combination with chemotherapy through drug-delivery devices to effectively kill cancer cells. In this way, the nanoparticles act as heating sources or “hot spots,” which can trigger cellular responses in the absence of a global temperature rise, making the tumor cells more sensitive to chemotherapeutics. The fabrication of optical and magnetic drug-delivery devices, the heating mechanisms, and their applications in tumor treatment are also summarized.Item 3D scaffold with effective multidrug sequential release against bacteria biofilm(Acta Biomaterialia, 2016) García Álvarez, Rafaela; Izquierdo Barba, Isabel; Vallet Regí, María Dulce NombreBone infection is a feared complication following surgery or trauma that remains as an extremely difficult disease to deal with. So far, the outcome of therapy could be improved with the design of 3D implants, which combine the merits of osseous regeneration and local multidrug therapy so as to avoid bacterial growth, drug resistance and the feared side effects. Herein, hierarchical 3D multidrug scaffolds based on nanocomposite bioceramic and polyvinyl alcohol (PVA) prepared by rapid prototyping with an external coating of gelatin-glutaraldehyde (Gel-Glu) have been fabricated. These 3D scaffolds contain three antimicrobial agents (rifampin, levofloxacin and vancomycin), which have been localized in different compartments of the scaffold to obtain different release kinetics and more effective combined therapy. Levofloxacin was loaded into the mesopores of nanocomposite bioceramic part, vancomycin was localized into PVA biopolymer part and rifampin was loaded in the external coating of Gel-Glu. The obtained results show an early and fast release of rifampin followed by sustained and prolonged release of vancomycin and levofloxacin, respectively, which are mainly governed by the progressive in vitro degradability rate of these scaffolds. This combined therapy is able to destroy Gram-positive and Gram-negative bacteria biofilms as well as inhibit the bacteria growth; in addition, these multifunctional scaffolds exhibit excellent bioactivity as well as good biocompatibility with complete cell colonization of preosteoblast in the entire surface, ensuring good bone regeneration. These findings suggest that these hierarchical 3D multidrug scaffolds are promising candidates as platforms for local bone infection therapy.Item Mesoporous Silica Nanoparticles in Nanomedicine applications(Journal of Materials Science: Materials in Medicine, 2018) Manzano García, Miguel; Vallet Regí, María Dulce NombreIn the last few years Mesoporous Silica Nanoparticles (MSNs) have gained the attention of the nanomedicine research community, especially for the potential treatment of cancer. Although this topic has been reviewed before, periodic updates on such a hot topic are necessary due to the dynamic character of this field. The reasons that make MSNs so attractive for designing controlled drug delivery systems lie beneath their physico-chemical stability, easy functionalisation, low toxicity and their great loading capacity of many different types of therapeutic agents. The present brief overview tries to cover some of the recent findings on stimuli-responsive mesoporous silica nanocarriers together with the efforts to design targeted nanosystems using that platform. The versatility of those smart nanocarriers has promoted them as very promising candidates to be used in the clinic in the near future to overcome some of the pitfalls of conventional medicine.Item Concanavalin A-targeted mesoporous silica nanoparticles for infection treatment.(Acta Biomaterialia, 2019) Martínez Carmona, Marina; Izquierdo Barba, Isabel; Colilla Nieto, Montserrat; Vallet Regí, María Dulce NombreThe ability of bacteria to form biofilms hinders any conventional treatment for chronic infections and has serious socio-economic implications. For this purpose, a nanocarrier capable of overcoming the barrier of the mucopolysaccharide matrix of the biofilm and releasing its loadedantibiotic within this matrix would be desirable. Herein, we developed a new nanosystem based on levofloxacin (LEVO)-loaded mesoporous silica nanoparticles (MSNs) decorated with the lectin concanavalin A (ConA). The presence of ConA promotes the internalization of this nanosystem into the biofilm matrix, which increases the antimicrobial efficacy of the antibiotic hosted within the mesopores. This nanodevice is envisioned as a promising alternative to conventional treatments for infection by improving the antimicrobial efficacy and reducing side effects.