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Linking structure and optical properties of plasmonic nanoparticles on tunable spherical surfaces
Authors:
Francesco Brasili,
Angela Capocefalo,
Giovanni Del Monte,
Rodrigo Rivas-Barbosa,
Javier Pérez,
Edouard Chauveau,
Federico Bordi,
Carlo Rizza,
Domenico Truzzolillo,
Emanuela Zaccarelli,
Simona Sennato
Abstract:
The complexation of plasmonic nanoparticles (NPs) and thermoresponsive microgels is widely exploited for applications, but a microscopic description of the mechanisms governing the spatial organization of the NPs is still lacking. Combining small angle X-ray scattering, state-of-the-art simulations and a simple toy model, we uncover how the volume phase transition of microgels controls NP-NP inter…
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The complexation of plasmonic nanoparticles (NPs) and thermoresponsive microgels is widely exploited for applications, but a microscopic description of the mechanisms governing the spatial organization of the NPs is still lacking. Combining small angle X-ray scattering, state-of-the-art simulations and a simple toy model, we uncover how the volume phase transition of microgels controls NP-NP interactions, establishing for the first time a microscopic link between plasmon coupling and NP local structure. Our study paves the way to experimentally investigate phase transitions on controlled curved surfaces at the nanoscale.
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Submitted 27 March, 2025; v1 submitted 3 July, 2024;
originally announced July 2024.
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Influence of drug/lipid interaction on the entrapment efficiency of isoniazid in liposomes for antitubercular therapy: a multi-faced investigation
Authors:
Francesca Sciolla,
Domenico Truzzolillo,
Edouard Chauveau,
Silvia Trabalzini,
Luisa Di Marzio,
Maria Carafa,
Carlotta Marianecci,
Angelo Sarra,
Federico Bordi,
Simona Sennato
Abstract:
Hypothesis. Isoniazid is one of the primary drugs used in tuberculosis treatment. Isoniazid encapsulation in liposomal vesicles can improve drug therapeutic index and minimize toxic and side effects. In this work, we consider mixtures of hydrogenated soy phosphatidylcholine/phosphatidylglycerol (HSPC/DPPG) to get novel biocompatible liposomes for isoniazid pulmonary delivery. Our goal is to unders…
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Hypothesis. Isoniazid is one of the primary drugs used in tuberculosis treatment. Isoniazid encapsulation in liposomal vesicles can improve drug therapeutic index and minimize toxic and side effects. In this work, we consider mixtures of hydrogenated soy phosphatidylcholine/phosphatidylglycerol (HSPC/DPPG) to get novel biocompatible liposomes for isoniazid pulmonary delivery. Our goal is to understand if the entrapped drug affects bilayer structure.
Experiments. HSPC-DPPG unilamellar liposomes are prepared and characterized by dynamic light scattering, $ζ$-potential, fluorescence anisotropy and Transmission Electron Microscopy. Isoniazid encapsulation is determined by UV and Laser Transmission Spectroscopy. Calorimetry, light scattering and Surface Pressure measurements are used to get insight on adsorption and thermodynamic properties of lipid bilayers in the presence of the drug.
Findings. We find that INH-lipid interaction can increase the entrapment capability of the carrier due to isoniazid adsorption. The preferential INH-HSPC dipole-dipole interaction promotes modification of lipid packing and ordering and favors the condensation of a HSPC-richer phase in molar excess of DPPG. Our findings highlight the importance of fundamental investigations of drug-lipid interactions for the optimal design of liposomal nanocarriers.
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Submitted 26 January, 2021;
originally announced January 2021.
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Assembling patchy plasmonic nanoparticles with aggregation-dependent antibacterial activity
Authors:
Francesco Brasili,
Angela Capocefalo,
Damiano Palmieri,
Francesco Capitani,
Ester Chiessi,
Gaio Paradossi,
Federico Bordi,
Fabio Domenici
Abstract:
We realise an antibacterial nanomaterial based on the self-limited assembly of patchy plasmonic colloids, obtained by adsorption of lysozyme to gold nanoparticles. The possibility of selecting the size of the assemblies within several hundred nanometres allows for tuning their optical response in a wide range of frequencies from visible to near infrared. We also demonstrate an aggregation-dependen…
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We realise an antibacterial nanomaterial based on the self-limited assembly of patchy plasmonic colloids, obtained by adsorption of lysozyme to gold nanoparticles. The possibility of selecting the size of the assemblies within several hundred nanometres allows for tuning their optical response in a wide range of frequencies from visible to near infrared. We also demonstrate an aggregation-dependent modulation of the catalytic activity, which results in an enhancement of the antibacterial performances for assemblies of the proper size. The gained overall control on structure, optical properties and biological activity of such nanomaterial paves the way for the development of novel antibacterial nanozymes with promising applications in treating multi drug resistant bacteria.
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Submitted 27 July, 2020;
originally announced July 2020.
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Biophysical characterization of membrane phase transition profiles for the discrimination of Outer Membrane Vesicles (OMVs) from Escherichia coli grown at different temperatures
Authors:
Angelo Sarra,
Antonella Celluzzi,
Stefania Paola Bruno,
Caterina Ricci,
Simona Sennato,
Maria Grazia Ortore,
Stefano Casciardi,
Paolo Postorino,
Federico Bordi,
Andrea Masotti
Abstract:
Dynamic Light Scattering (DLS), Small Angle X-ray Scattering (SAXS) and Transmission Electron Microscopy (TEM) are physical techniques widely employed to characterize the morphology and the structure of vesicles such as liposomes or human extracellular vesicles (exosomes). Bacterial extracellular vesicles are similar in size to human exosomes, although their function and membrane properties have n…
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Dynamic Light Scattering (DLS), Small Angle X-ray Scattering (SAXS) and Transmission Electron Microscopy (TEM) are physical techniques widely employed to characterize the morphology and the structure of vesicles such as liposomes or human extracellular vesicles (exosomes). Bacterial extracellular vesicles are similar in size to human exosomes, although their function and membrane properties have not been elucidated in such detail as in the case of exosomes. Here, we applied the above cited techniques, in synergy with the thermodynamic characterization of the vesicles lipid membrane using a turbidimetric technique to the study of vesicles produced by Gram-negative bacteria (Outer Membrane Vesicles, OMVs) grown at different temperatures. This study demonstrated that our combined approach is useful to discriminate vesicles of different origin or coming from bacteria cultured under different experimental conditions. We envisage that in a near future the techniques employed in our work will be further implemented to discriminate complex mixtures of bacterial vesicles, thus showing great promises for biomedical or diagnostic applications.
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Submitted 28 November, 2019;
originally announced November 2019.