30 research outputs found

    Experimental studies on intermolecular, hydrodynamic and capillary interactions at the nanoscale

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    En la port.: Instituto de Microelectrónica de MadridTesis doctoral inédita leída en la Universidad Autónoma de Madrid. Facultad de Ciencias, Departamento de Física de la Materia Condensada. Fecha de lectura: 16-07-201

    Decrease of the adhesion force with vapor pressure

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    Trabajo presentado a NanoSpain 2010 celebrado en Málaga del 23-26 Marzo, 2010. -- Incluye comunicación oral y póster.Experimental evidence of a monotonous decrease of the capillary forces between hydrophilic surfaces with increasing relative humidity from 0 to 100% is presented. In concordance with the results of a theoretical simulation, we identified the objects’ shape as the origin of different adhesion force vs. RH behaviours when treating with nanoscale objects. If the water neck is formed between a flat surface and a nanometric object presenting a truncated cone shape the adhesion force decreases with increasing vapour pressure. The variety of meniscus force behaviours found for different shapes emphasizes the importance of geometry in capillary phenomena at the nanometric scale.Peer reviewe

    Quatsomes Loaded with Squaraine Dye as an Effective Photosensitizer for Photodynamic Therapy

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    Photodynamic therapy is a non-invasive therapeutic strategy that combines external light with a photosensitizer (PS) to destroy abnormal cells. Despite the great progress in the development of new photosensitizers with improved efficacy, the PS’s photosensitivity, high hydrophobicity, and tumor target avidity still represent the main challenges. Herein, newly synthesized brominated squaraine, exhibiting intense absorption in the red/near-infrared region, has been successfully incorporated into Quatsome (QS) nanovesicles at different loadings. The formulations under study have been characterized and interrogated in vitro for cytotoxicity, cellular uptake, and PDT efficiency in a breast cancer cell line. The nanoencapsulation of brominated squaraine into QS overcomes the non-water solubility limitation of the brominated squaraine without compromising its ability to generate ROS rapidly. In addition, PDT effectiveness is maximized due to the highly localized PS loadings in the QS. This strategy allows using a therapeutic squaraine concentration that is 100 times lower than the concentration of free squaraine usually employed in PDT. Taken together, our results reveal the benefits of the incorporation of brominated squaraine into QS to optimize their photoactive properties and support their applicability as photosensitizer agents for PDT

    Antibiofilm surfaces based on the immobilization of a novel recombinant antimicrobial multidomain protein using self-assembled monolayers

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    The constant increase of microorganisms resistant to antibiotics has been classified as a global health emergency, which is especially challenging when biofilms are formed. Herein, novel biofunctionalized gold surfaces with the antimicrobial multidomain recombinant protein JAMF1, both in the soluble form and nanostructured as nanoparticles, were developed. The interaction between His-tag termination of the protein and a nitriloacetic acid–Ni complex formed on mixed self-assembled monolayers (mixed SAMs) was exploited. The obtained antibiofilm surfaces based on the immobilization of the novel JAMF1 protein using self-assembled monolayers were characterized using a multi-technique approach including: cyclic voltammetry, X-ray photoelectron spectroscopy, atomic force microscopy and fluorescence, proving that the modification and immobilization of JAMF1 were successfully done. The antibiofilm activity against Escherichia coli and carbapenem-resistant Klebsiella pneumoniae showed that the immobilized antimicrobial proteins were able to reduce biofilm formation of both microorganisms. This strategy opens up new possibilities for controlled biomolecule immobilization for fundamental biological studies and biotechnological applications, at the interface of materials science and molecular biology.info:eu-repo/semantics/publishedVersio

    Ultrabright Föster Resonance Energy Transfer Nanovesicles:The Role of Dye Diffusion

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    The development of contrast agents based on fluorescent nanoparticles with high brightness and stability is a key factor to improve the resolution and signal-to-noise ratio of current fluorescence imaging techniques. However, the design of bright fluorescent nanoparticles remains challenging due to fluorescence self-quenching at high concentrations. Developing bright nanoparticles showing FRET emission adds several advantages to the system, including an amplified Stokes shift, the possibility of ratiometric measurements, and of verifying the nanoparticle stability. Herein, we have developed Förster resonance energy transfer (FRET)-based nanovesicles at different dye loadings and investigated them through complementary experimental techniques, including conventional fluorescence spectroscopy and super-resolution microscopy supported by molecular dynamics calculations. We show that the optical properties can be modulated by dye loading at the nanoscopic level due to the dye's molecular diffusion in fluid-like membranes. This work shows the first proof of a FRET pair dye's dynamism in liquid-like membranes, resulting in optimized nanoprobes that are 120-fold brighter than QDot 605 and exhibit >80% FRET efficiency with vesicle-to-vesicle variations that are mostly below 10%.J.M.-F. gratefully thanks the financial support received by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 712949 (TECNIOspring PLUS) and from the Agency for Business Competitiveness of the Government of Catalonia. We acknowledge the European Commission (EC) FP7-PEOPLE-2013-Initial Training Networks (ITN) “NANO2FUN” project no. 607721 for being the spark that initiates this work and EC project MSCA-RISE-2020 "MICRO4NANO" project no.101007804. This work was also financially supported by Generalitat de Catalunya (grant no. 2017-SGR-918), the Ministry of Economy, Industry, and Competitiveness (Spain), through the “MOTHER” project (MAT2016-80826-R), the Ministry of Science and Innovation of Spain through the grant PID2019-105622RB-I00 (Mol4Bio). ICMAB-CSIC also acknowledges support from the MINECO through the Severo Ochoa Programme FUNFUTURE (SEV-2015-0496 and CEX2019-000917-S). K.D.B. acknowledges the National Science Foundation (CBET-1517273 and CHE-1726345). C.S. and A.P. benefited from the equipment and framework of the COMP-HUB Initiative, funded by the “Departments of Excellence” program of the Italian Ministry for Education, University and Research (MIUR, 2018-2022). We thank the CESGA Supercomputing Center for technical support and the use of computational resources. The contribution of S.I.-T. has been done under the Materials Science PhD program in the Barcelona Autonomous University (UAB). Characterizations of nanovesicles were made at the ICTS “NANBIOSIS”, more specifically by the U6 unit of CIBER-BBN. The authors would like also to thank the collaboration of Hamamatsu Photonics for the quantum yield determinations using the Quantaurus-QY Plus UV–NIR absolute PL quantum yield spectrometer.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe

    Engineering pH-Sensitive Stable Nanovesicles for Delivery of MicroRNA Therapeutics

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    Nanovesicles; Neuroblastoma; Pediatric cancerNanovesículas; Neuroblastoma; Cáncer pediátricoNanovesícules; Neuroblastoma; Càncer pediàtricMicroRNAs (miRNAs) are small non-coding endogenous RNAs, which are attracting a growing interest as therapeutic molecules due to their central role in major diseases. However, the transformation of these biomolecules into drugs is limited due to their unstability in the bloodstream, caused by nucleases abundantly present in the blood, and poor capacity to enter cells. The conjugation of miRNAs to nanoparticles (NPs) could be an effective strategy for their clinical delivery. Herein, the engineering of non-liposomal lipid nanovesicles, named quatsomes (QS), for the delivery of miRNAs and other small RNAs into the cytosol of tumor cells, triggering a tumor-suppressive response is reported. The engineered pH-sensitive nanovesicles have controlled structure (unilamellar), size (24 weeks), and are prepared by a green, GMP compliant, and scalable one-step procedure, which are all unavoidable requirements for the arrival to the clinical practice of NP based miRNA therapeutics. Furthermore, QS protect miRNAs from RNAses and when injected intravenously, deliver them into liver, lung, and neuroblastoma xenografts tumors. These stable nanovesicles with tunable pH sensitiveness constitute an attractive platform for the efficient delivery of miRNAs and other small RNAs with therapeutic activity and their exploitation in the clinics.The funding was received by Ministerio de Educación, Cultura y Deporte (Grant no. FPU16/01099), Ministerio de Economía, Industria y Competividad (Grants MAT2016-80820-R, MAT2016-80826-R and SAF2016-75241-R), the Ministry of Science and Innovation (MINECO) of Spain through grant PID2019-105622RB-I00, from Instituto de Salud Carlos III (Grant no. CP16/00006, PI17/00564, PI20/00530, DTS20/00018) (Co-funded by European Regional Development Fund/European Social Fund) “Investing in your future”), from the EuroNanoMed II platform through the NanoVax project, from CIBER-BBN through grant TAG-SMARTLY, Joan Petit Foundation, Asociación Matem Lo Bitxo and Asociación Española Contra el Cáncer (Grant no. LABAE18009SEGU), as well as, Generalitat de Catalunya through the Centres de Recerca de Catalunya (CERCA) programme and grant no. 2017-SGR-918, and from Agency for Management of University and Research Grants (AGAUR) (Grant no 2018LLAV0064 and SIFECAT IU68-010017). Furthermore, ICMAB-CSIC acknowledges support from the MINECO through the Severo Ochoa Programme for Centres of Excellence in R&D (SEV-2015-0496 and CEX2019-000917-S)

    Engineering DNA-Grafted Quatsomes as Stable Nucleic Acid-Responsive Fluorescent Nanovesicles

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    The development of artificial vesicles into responsive architectures capable of sensing the biological environment and simultaneously signaling the presence of a specific target molecule is a key challenge in a range of biomedical applications from drug delivery to diagnostic tools. Herein, the rational design of biomimetic DNA-grafted quatsome (QS) nanovesicles capable of translating the binding of a target molecule to amphiphilic DNA probes into an optical output is presented. QSs are synthetic lipid-based nanovesicles able to confine multiple organic dyes at the nanoscale, resulting in ultra-bright soft materials with attractiveness for sensing applications. Dye-loaded QS nanovesicles of different composition and surface charge are grafted with fluorescent amphiphilic nucleic acid-based probes to produce programmable FRET-active nanovesicles that operate as highly sensitive signal transducers. The photophysical properties of the DNA-grafted nanovesicles are characterized and the highly selective, ratiometric detection of clinically relevant microRNAs with sensitivity in the low nanomolar range are demonstrated. The potential applications of responsive QS nanovesicles for biosensing applications but also as functional nanodevices for targeted biomedical applications is envisaged.This work was financially supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska- Curie grant agreement “Nano-Oligo Med” (No 778133), Ministry of Science and Innovation (MINECO), Spain, through the “MOL4BIO” project (PID2019-105622RB-I00) and by Instituto de Salud Carlos III (DTS20/00018), Italian Ministry of University and Research (Project of National Interest, PRIN, 2017Y2PAB8_004 through the project “Cutting Edge Analytical Chemistry Methodologies and Bio-Tools to Boost Precision Medicine in Hormone-Related Diseases”. M.R. was supported from a Fondazione Umberto Veronesi postdoctoral fellowship. Furthermore, ICMAB-CSIC acknowledges support from the MINECO through the Severo Ochoa Programme for Centers of Excellence in R&D (SEV-2015-0496 and CEX2019-000917-S). Quatsome production and their physicochemical characterization has been performed by the Biomaterial Processing and Nanostructuring Unit (U6) of the ICTS “NANBIOSIS”, a unit of the CIBER network in Bioengineering, Biomaterials & Nanomedicine (CIBER-BBN) located at the Institute of Materials Science of Barcelona (ICMAB-CSIC).Peer reviewe

    Dye-Loaded Quatsomes Exhibiting FRET as Nanoprobes for Bioimaging

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    Fluorescent organic nanoparticles (FONs) are emerging as an attractive alternative to the well-established fluorescent inorganic nanoparticles or small organic dyes. Their proper design allows one to obtain biocompatible probes with superior brightness and high photostability, although usually affected by low colloidal stability. Herein, we present a type of FONs with outstanding photophysical and physicochemical properties in-line with the stringent requirements for biomedical applications. These FONs are based on quatsome (QS) nanovesicles containing a pair of fluorescent carbocyanine molecules that give rise to Förster resonance energy transfer (FRET). Structural homogeneity, high brightness, photostability, and high FRET efficiency make these FONs a promising class of optical bioprobes. Loaded QSs have been used for in vitro bioimaging, demonstrating the nanovesicle membrane integrity after cell internalization, and the possibility to monitor the intracellular vesicle fate. Taken together, the proposed QSs loaded with a FRET pair constitute a promising platform for bioimaging and theranostics.J.M.F. gratefully thank the financial support received by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 712949 (TECNIOspring PLUS) and from the Agency for Business Competitiveness of the Government of Catalonia (TECSPR17-1-0035). This work was also financially supported by the Ministry of Economy, Industry, and Competitiveness, Spain, through the “MOTHER” project (MAT2016-80826-R) and the “FLOWERS” project (FUNMAT-FIP-2016) funded by the Severo Ochoa (SEV-2015-0496) awarded to ICMAB. Instituto de Salud Carlos III, through “Acciones CIBER”, also supported this work. Characterization of nanovesicles was made at the ICTS “NANBIOSIS”, more specifically by the U6 unit of CIBER-BBN. The authors acknowledge the European Commission (EC) FP7-PEOPLE-2013-Initial Training Networks (ITN) “NANO2FUN” project no. 607721 for being the spark that initiated this work. K.B.D. acknowledges support from the National Science Foundation (CBET-1517273 and CHE-1726345). C.S. and A.P. benefited from the equipment and framework of the COMP-HUB Initiative, funded by the “Departments of Excellence” program of the Italian Ministry for Education, University and Research (MIUR, 2018-2022).Peer reviewe

    Antibiofilm surfaces based on the immobilization of a novel recombinant antimicrobial multidomain protein using self-assembled monolayers

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    The constant increase of microorganisms resistant to antibiotics has been classified as a global health emergency, which is especially challenging when biofilms are formed. Herein, novel biofunctionalized gold surfaces with the antimicrobial multidomain recombinant protein JAMF1, both in the soluble form and nanostructured as nanoparticles, were developed. The interaction between His-tag termination of the protein and a nitriloacetic acid-Ni complex formed on mixed self-assembled monolayers (mixed SAMs) was exploited. The obtained antibiofilm surfaces based on the immobilization of the novel JAMF1 protein using self-assembled monolayers were characterized using a multi-technique approach including: cyclic voltammetry, X-ray photoelectron spectroscopy, atomic force microscopy and fluorescence, proving that the modification and immobilization of JAMF1 were successfully done. The antibiofilm activity against Escherichia coli and carbapenem-resistant Klebsiella pneumoniae showed that the immobilized antimicrobial proteins were able to reduce biofilm formation of both microorganisms. This strategy opens up new possibilities for controlled biomolecule immobilization for fundamental biological studies and biotechnological applications, at the interface of materials science and molecular biology.This work has been developed under the Biochemistry and Biomedicine and Materials Science Program of Universitat Autònoma de Barcelona (UAB). The characterization has been performed by the ICTS ‘‘NANBIOSIS’’, more specifically by the Biomaterial Processing and Nanostructuring Unit (U6), Unit of CIBER-BBN located at ICMAB-CSIC. Authors are grateful for the financial support received from MICINN (PID2020-115296RA-I00 and PID2019–105622RB-I00), the Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN), GenCat (grant 2017-SGR-918, SGR Cat 2021-00438 and CERCA programme), the European Social Fund, and Fundació La Marató de TV3 (Nr. 201812). This project has received funding from the European Union's Horizon 2020 research and innovation program under the HORIZON-RIA project NABIHEAL (GA number 101092269), the Marie Skłodowska-Curie grant agreement No. 801342 (Tecniospring INDUSTRY) and the Government of Catalonia's Agency for Business Competitiveness (ACCIÓ; TECSPR19-1-0065). J.G. is grateful to MICINN for a ‘‘Ramón y Cajal’’ fellowship (RYC-2017-22614) as well as to the Max Planck Society through the Max Planck Partner Group “Dynamic Biomimetics for Cancer Immunotherapy” in collaboration with the Max Planck Institute for Medical Research (Heidelberg, Germany). R.R-P received a PhD fellowship from Secretaria d’Universitats i Recerca del Departament d’Economia i Coneixement de la Generalitat de Catalunya (AGAUR) and E.G-F a post-doctoral fellowship from INIA (DOC-INIA). ICMAB-CSIC acknowledges the support from the Severo Ochoa Programme for Centres of Excellence in R&D (FUNFUTURE, CEX2019-000917-S). Table of contents entry and Fig. 2 were designed with BioRender.com.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe
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