Person: Guerrero Martínez, Andrés
Loading...
First Name
Andrés
Last Name
Guerrero Martínez
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Física
Area
Química Física
Identifiers
7 results
Search Results
Now showing 1 - 7 of 7
Item Gemini Cationic Lipid-Type Nanovectors Suitable for the Transfection of Therapeutic Plasmid DNA Encoding for Pro-Inflammatory Cytokine Interleukin-12(Pharmaceutics, 2021) Sánchez Arribas, Natalia; Martínez Negro, María; Aicart Ramos, Clara; Tros de Ilarduya, Conchita; Aicart Sospedra, Emilio; Guerrero Martínez, Andrés; Junquera González, ElenaAmple evidence exists on the role of interleukin-12 (IL-12) in the response against many pathogens, as well as on its remarkable antitumor properties. However, the unexpected toxicity and disappointing results in some clinical trials are prompting the design of new strategies and/or vectors for IL-12 delivery. This study was conceived to further endorse the use of gemini cationic lipids (GCLs) in combination with zwitterionic helper lipid DOPE (1,2-dioleoyl-sn-glycero-3-phosphatidyl ethanol amine) as nanovectors for the insertion of plasmid DNA encoding for IL-12 (pCMV-IL12) into cells. Optimal GCL formulations previously reported by us were selected for IL-12-based biophysical experiments. In vitro studies demonstrated efficient pCMV-IL12 transfection by GCLs with comparable or superior cytokine levels than those obtained with commercial control Lipofectamine2000*. Furthermore, the nanovectors did not present significant toxicity, showing high cell viability values. The proteins adsorbed on the nanovector surface were found to be mostly lipoproteins and serum albumin, which are both beneficial to increase the blood circulation time. These outstanding results are accompanied by an initial physicochemical characterization to confirm DNA compaction and protection by the lipid mixture. Although further studies would be necessary, the present GCLs exhibit promising characteristics as candidates for pCMV-IL12 transfection in future in vivo applications.Item Nanocapillarity and the liquid bridge mediated force between colloidal nanoparticles(ACS Omega, 2018) MacDowell, Luis G.; Llombart, Pablo; Benet, Jorge; Palanco, Jose; Guerrero Martínez, AndrésIn this work we probe the concept of interface tension for ultra thin adsorbed liquid films in the nanoscale by studying the surface fluctuations of films down to the monolayer. Our results show that the spectrum of film height fluctuations of a liquid-vapor surface may be extended to ultra thin films provided we take into account the interactions of the substrate with the surface. Global fluctuations of film height are described in terms of the disjoining pressure, while surface deformations that are proportional to the interface area are accounted for by a film thick dependent surface tension. As a prove of concept, we model the capillary forces between colloidal nanoparticles held together by liquid bridges. Our results indicate that the classical equations for capillarity follow very precisely down to the nanoscale, provided we account for the film height dependence of the surface tension.Item Intracellular pH-Induced Tip-to-Tip Assembly of Gold Nanorods for Enhanced Plasmonic Photothermal Therapy(ACS Omega, 2016) Ahijado Guzmán, Rubén; Bañares Morcillo, Luis; Guerrero Martínez, Andrés; López Montero, Iván; Tardajos Rodríguez, Gloria María; González Rubio, Guillermo; Izquierdo, Jesús G.; Calzado Martín, Alicia; Calleja, MontserratThe search for efficient plasmonic photothermal therapies using nonharmful pulse laser irradiation at the near-infrared (NIR) is fundamental for biomedical cancer research. Therefore, the development of novel assembled plasmonic gold nanostructures with the aim of reducing the applied laser power density to a minimum through hot-spot-mediated cell photothermolysis is an ongoing challenge. We demonstrate that gold nanorods (Au NRs) functionalized at their tips with a pH-sensitive ligand assemble into oligomers within cell lysosomes through hydrogen-bonding attractive interactions. The unique intracellular features of the plasmonic oligomers allow us to significantly reduce the femtosecond laser power density and Au NR dose while still achieving excellent cell killing rates. The formation of gold tip-to-tip oligomers with longitudinal localized surface plasmon resonance bands at the NIR, obtained from low-aspect-ratio Au NRs close in resonance with 800 nm Ti:sapphire 90 fs laser pulses, was found to be the key parameter for realizing the enhanced plasmonic photothermal therapy.Item Effectiveness of Gold Nanorods of Different Sizes in Photothermal Therapy to Eliminate Melanoma and Glioblastoma Cells(International Journal of Molecular Sciences, 2023) Domingo-Diez, Javier; Souiade, Lilia; Manzaneda González, Vanesa; Sánchez-Díez, Marta; Megias, Diego; Guerrero Martínez, Andrés; Ramírez-Castillejo, Carmen; Serrano-Olmedo, Javier; Ramos-Gómez, MilagrosGold nanorods are the most commonly used nanoparticles in photothermal therapy for cancer treatment due to their high efficiency in converting light into heat. This study aimed to investigate the efficacy of gold nanorods of different sizes (large and small) in eliminating two types of cancer cell: melanoma and glioblastoma cells. After establishing the optimal concentration of nanoparticles and determining the appropriate time and power of laser irradiation, photothermal therapy was applied to melanoma and glioblastoma cells, resulting in the highly efficient elimination of both cell types. The efficiency of the PTT was evaluated using several methods, including biochemical analysis, fluorescence microscopy, and flow cytometry. The dehydrogenase activity, as well as calcein-propidium iodide and Annexin V staining, were employed to determine the cell viability and the type of cell death triggered by the PTT. The melanoma cells exhibited greater resistance to photothermal therapy, but this resistance was overcome by irradiating cells at physiological temperatures. Our findings revealed that the predominant cell-death pathway activated by the photothermal therapy mediated by gold nanorods was apoptosis. This is advantageous as the presence of apoptotic cells can stimulate antitumoral immunity in vivo. Considering the high efficacy of these gold nanorods in photothermal therapy, large nanoparticles could be useful for biofunctionalization purposes. Large nanorods offer a greater surface area for attaching biomolecules, thereby promoting high sensitivity and specificity in recognizing target cancer cells. Additionally, large nanoparticles could also be beneficial for theranostic applications, involving both therapy and diagnosis, due to their superior detection sensitivity.Item Microfluidic fabrication of vesicles with hybrid lipid/nanoparticle bilayer membranes(Soft Matter, 2019) Julie Perrotton; Ahijado Guzmán, Rubén; Lara H Moleiro; Berta Tinao; Guerrero Martínez, Andrés; Esther Amstad; Monroy Muñoz, Francisco; Laura R ArriagaHybrid lipid/nanoparticle membranes are suitable model systems both to study the complex interactions between nanoparticles and biological membranes, and to demonstrate technological concepts in cellular sensing and drug delivery. Unfortunately, embedding nanoparticles into the bilayer membrane of lipid vesicles is challenging due to the poor control over the vesicle fabrication process of conventional methodologies and the fragility of the modified lipid bilayer assembly. Here, the utility of water-in-oil-in-water double emulsion drops with ultrathin oil shells as templates to form vesicles with hybrid lipid/nanoparticle membranes is reported.Item Tunable gold nanorod/NAO conjugates for selective drug delivery in mitochondria-targeted cancer therapy(Nanoscale, 2022) González-Rubio, Sergio; Salgado, Cástor; Manzaneda González, Vanesa; Muñoz Úbeda, Mónica; Ahijado Guzmán, Rubén; Natale, Paolo; Almendro Vedia, Víctor Galileo; Junquera González, María Elena; Osío Barcina, José De Jesús; Ferrer, Irene; Guerrero Martínez, Andrés; Paz-Ares Rodríguez, Luis Gonzaga; López Montero, IvánItem From multi- to single-hollow trimetallic nanocrystals by ultrafast heating(Chemistry of Materials, 2023) Manzaneda González, Vanesa; Jenkinson, Kellie; Peña-Rodríguez, Ovidio; Borrell Grueiro, Olivia; Triviño-Sánchez, Sergio; Bañares Morcillo, Luis; Junquera González, María Elena; Espinosa, Ana; González-Rubio, Guillermo; Bals, Sara; Guerrero Martínez, AndrésMetal nanocrystals (NCs) display unique physicochemical features that are highly dependent on the nanoparticle dimensions, anisotropy, structure, and composition. The development of synthesis methodologies that allow us to tune such parameters finely emerges crucial for the application of metal NCs in catalysis, optical materials, or biomedicine. Here, we describe a synthetic methodology to fabricate hollow multimetallic heterostructures using a combination of seed-mediated growth routes and femtosecond pulsed laser irradiation. The envisaged methodology relies on the co-reduction of Ag and Pd ions on gold nanorods (Au NRs) to form Au@PdAg core–shell nanostructures containing small cavities at the Au-PdAg interface. The excitation of Au@PdAg NRs with low fluence femtosecond pulses was employed to induce the coalescence and growth of large cavities, forming multihollow anisotropic Au@PdAg nanostructures. Moreover, single-hollow alloy AuPdAg could be achieved in high yield by increasing the irradiation energy. Advanced electron microscopy techniques, energy-dispersive X-ray spectroscopy (EDX) tomography, X-ray absorption near edge structure (XANES) and FDTD (finite differences in the time domain) simulationsallowed us to characterize the morphology, structure, and elemental distribution of the irradiated NCs in detail. The ability of the reported synthesis route to fabricate multimetallic NCs with unprecedented hollow nanostructures brings attractive prospects for the fabrication of tailored high-entropy alloy nanoparticles.