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Pneumococcal conjugate vaccines offer an excellent safety profile and high protection against the serotypes comprised in the vaccine. However, inclusion of protein antigens fromStreptococcus pneumoniaecombined with potent adjuvants and a suitable delivery system are expected to both extend protection to serotype strains not represented in the formulation and stimulate a broader immune response, thus more effective in young children, elderly, and immunocompromised populations. Along this line, nanoparticle (NP) delivery systems can enhance the immunogenicity of antigens by protecting them from degradation and increasing their uptake by antigen-presenting cells, as well as offering co-delivery with adjuvants. We report herein the encapsulation of a semisynthetic glycoconjugate (GC) composed of a synthetic tetrasaccharide mimicking theS. pneumoniae serotype 14 capsular polysaccharide (CP14) linked to the Pneumococcal surface protein A (PsaA) using chitosan NPs (CNPs). These GC-loaded chitosan nanoparticles (GC-CNPs) were not toxic to human monocyte-derived dendritic cells (MoDCs), showed enhanced uptake, and displayed better immunostimulatory properties in comparison to the naked GC. A comparative study was carried out in mice to evaluate the immune response elicited by the glycoconjugate-administered subcutaneously (SC), where the GC-CNPs displayed 100-fold higher IgG response as compared with the group treated with nonencapsulated GC. Overall, the study demonstrates the potential of this chitosan-based nanovaccine for efficient delivery of glycoconjugate antigens.

[ES] La combinación de la plasmónica y la optomecánica molecular está demostrando ser un campo potencialmente prometedor para el desarrollo de sensores de THz integrados que permiten acoplar esta señal a la del espectro visible, proporcionando un nuevo abanico de oportunidades de diagnóstico prácticamente inocuo para el paciente. La espectroscopia Raman es un aspecto clave en este caso, ya que ofrece la posibilidad de detectar la señal resultante del acople de señales. Por ello, el desarrollo de nuevas metodologías experimentales es esencial para generar y caracterizar las estructuras nanofotónicas que compondrán estos detectores de THz. En este trabajo, se han utilizado dos tipos de moléculas para funcionalizar las superficies plasmónicas, las cuales permiten el acoplamiento de señales en estos rangos de frecuencia. Estas son el Biphenil-4-tiol (BPT) y el 5-amino-2- mercaptobenzimidazole (ABIZ), habiendo desarrollado para esta última nueva técnica de funcionalización de superficies. Para generar las estructuras plasmónicas, se han depositado nanopartículas (NPs) de oro en la superficie de estructuras litografiadas mediante dos metodologías, siendo una de ellas una nueva técnica de transferencia de NPs que se ha denominado \textit{micro-contact printing}. Estas estructuras han sido caracterizadas con éxito mediante distintas técnicas. También se ha ensamblado un nuevo setup experimental para realizar Espectroscopia Raman mejorada por guía de ondas (WERS), lo cual es importante para simular las condiciones de guiado de la onda, así como para caracterizar dichos circuitos. Por ultimo, se han realizado simulaciones para determinar posibles estructuras plasmónicas nuevas que permitan el acoplamiento de las señales., [CA] La combinacio de la plasm ´ onica i l’optomec ´ anica molecular est ´ a demostrant ser un camp potencial- ` ment prometedor per al desenrotllament de sensors de THz integrats que permeten acoblar este senyal a la de l’espectre visible, proporcionant un nou palmito d’oportunitats de diagnostic pr ` acticament ` innocu per al pacient. L’espectroscopia Raman ` es un aspecte clau en este cas, ja que oferix la pos- ´ sibilitat de detectar el senyal resultant de l’acoble de senyals. Per aixo, el desenrotllament de noves ` metodologies experimentals es essencial per a generar i caracteritzar les estructures nanofot ´ onicas que ´ compondran estos detectors de THz. En aquest treball, s’han utilitzat dos tipus de molecules per a fun- ` cionalizar les superf´ıcies plasmoniques, les quals permeten l’adaptament de senyals en estos rangs de ` frequ¨encia. Estes s ` on el Biphenil-4-tiol (BPT) i el 5-amino-2-mercaptobenzimidazole (ABIZ), havent ´ desenvolupat per a aquesta ultima una nova t ´ ecnica de funcionalitzaci ` o de superf ´ ´ıcies. Per a generar les estructures plasmoniques, s’han depositat nanopart ` ´ıculas (NPs) d’or en la superf´ıcie d’estructures litografiades per mitja de dos metodologies, sent una d’elles una nova t ` ecnica de transfer ` encia de ` NPs que s’ha denominat micro-contact printing. Estes estructures han sigut caracteritzades amb exit per mitj ` a de distintes t ` ecniques. Tamb ` e s’ha generat un nou setup experimental per a realitzar ´ Espectroscopia Raman millorada per guia d’ones (WERS), la qual cosa ` es important per a simular ´ les condicions de guiat de l’onda, aix´ı com per a caracteritzar els mencionats circuits. Per ultim, ´ s’han realitzat simulacions per a determinar possibles estructures plasmoniques noves que permeten ` l’adaptament de les senyals, [EN] Combining plasmonics and molecular optomechanics is proving to be a potentially promising approach for the development of integrated THz sensors which allow the coupling of this signal to the visible spectrum, providing a new range of diagnostic opportunities that are virtually innocuous for the patient. Raman spectroscopy is a key issue here, as it offers the possibility to detect the resulting signal coupling. Therefore, the development of new experimental methodologies is essential to generate and characterize the nanophotonic structures that will compose these THz detectors. In this work, two types of molecules have been used to functionalize the plasmonic surfaces, which allow the coupling of signals in these frequency ranges. These are Biphenyl-4-thiol (BPT) and 5-amino-2-mercaptobenzimidazole (ABIZ), having developed a new surface functionalization technique for the latter. In order to generate the plasmonic structures, gold nanoparticles (NPs) have been deposited on the surface of lithographed structures by two methodologies, one of them being a new NPs transfer technique called micro-contact printing. These structures have been successfully characterized using different techniques. A new experimental setup has also been assembled to perform Waveguide Enhanced Raman Spectroscopy (WERS), which is important to simulate the wave-guiding conditions, as well as to characterize such circuits. Finally, simulations have been performed to determine possible new photonic nanostructures for signal coupling.

A wide range of nanomaterials have been developed for biomedical applications, such as drug delivery, biomedical imaging, and sensors. Nanomaterials can include nanoparticles (NPs) and nanofibers with various dimensions that are both natural and synthetic. A successful nanomaterial, for use in biological applications, is characterized by its biocompatibility, biodegradability, intrinsic high surfaces area, high interconnected porosity, and functionality. These features were achieved with the development of metal-organic framework (MOF) nanostructures. MOFs are assemblies of metal ions and organic linkers that are built into different geometries and can exist in all dimensions (up to 3-D). The choice of linkers with well-defined shapes and connectivity to secondary building units (SBUs) allows for the desired design of MOF structures. Furthermore, these reticular materials can be post-synthetically modified and fine-tuned for specific biological properties. BioMOFs have proven their effective delivery of various molecular drug entities, however, a focus on these materials as a stand-alone treatment is needed. The intrinsic peroxidase activity of Cu2+ and its ability to cause oxidative stress in cancer and bacterial cells sparked our interest in studying and further evaluating the efficacy of copper-based MOFs as anti-cancer and anti-bacterial stand-alone treatments. Gallic Acid (GA), an edible phytochemical found in nature, can exhibit pro-oxidant and antioxidant properties by causing reactive oxidative species (ROS) accumulation while decreasing glutathione (GSH) levels in tumor cells. In this work, the effectiveness of Cu-BTC and Cu-GA MOFs were evaluated in gastric and colon cancer cell lines. The bacterial inhibition of gram-negative and gram-positive bacteria was also examined with both pristine MOFs. In addition, Cu-BTC, a microporous MOF, was chosen for the development of a hierarchical structure containing both micro-and mesopores for the intend

This article discusses the requirements for reference materials (RMs) for measuring the size of nanoparticles (NPs). Such RMs can be used for instrument calibration, statistical quality control or interlaboratory comparisons. They can come in the form of suspensions, powders or matrix-embedded materials [i.e. NPs integrated in a natural matrix (e.g., food, soil, or sludge)]. At present, uncertainty about the most suitable form of material, the most relevant measurands and the most useful metrological-traceability statement inhibits the production of NP RMs. In addition, the lack of validated methods and qualified laboratories to produce NP RMs present formidable challenges. Metal, inorganic and organic NPs are available, but most of them are intended to be laboratory chemicals. With the exception of latex materials, certified RMs are not available, although some metrology institutes have started to develop such materials for colloidal gold and silica particles.

Polymerní nanokompozity (PNCs) mají slibnou budoucnost jako lehké funkční materiály zpracovatelné aditivními výrobními technologiemi. Jejich rychlému rozšíření však brání silná závislost jejich užitných vlastností na prostorovém uspořádání nanočástic (NP). Schopnost řídit disperzi nanočástic je tak klíčovým předpokladem pro jejich uplatnění ve funkčních kompozitech. Tato práce zkoumá přípravu polymerních nanokompozitů v modelové sklotvorné polymerní matrici roztokovou metodou, technikou schopnou vytvářet prostorové uspořádání nanočástic řízené strukturními a kinetickými parametry přípravného procesu. Prezentované výsledky popisují rozdíly mezi změnami rheologického chování roztoku polystyrenu při oscilačním smyku s vysokou amplitudou (LAOS) vyvolanými nanočásticemi. Výsledky vedou k závěru, že vysoce-afinní OP-POSS nanočástice při nízkých koncentracích dobře interagují s PS a tvoří tuhé agregáty, zatímco nízko-afinní OM-POSS nanočástice za těchto podmínek neovlivňují deformační chování polymerních řetězců. Dále byla pozornost zaměřena na vliv použitého rozpouštědla na uspořádání nanočástic v SiO2/PMMA a SiO2/PS nanokompozitech, který je v literatuře prezentován jako parametr řídící prostorové uspořádání nanočástic v pevném stavu. Důraz byl kladen na kvalitativní rozdíly mezi „špatně dispergovanými“ shluky nanočástic, které byly na základě rheologie a strukturální analýzy (TEM, USAXS) identifikovány jako polymerními řetězci vázané nanočásticové klastry a dva typy agregátů, jeden termodynamického a druhý kinetického původu. Jednotlivé druhy agregátů se vyznačují odlišnými kinetikami vzniku a rozdílnými vlastnostmi jak mezi sebou, tak v porovnání s dispergovanými nanočásticemi. Pozorované typy disperze nanočástic byly kvantitativně posouzeny podle svých rheologických vlastností během roztokové přípravy, podle kterých byla vyhodnocena míra adsorpce polymeru na povrch nanočástic a atrakce ve vypuzeném objemu. Výsledky byly porovnány s teorií PRISM. Důležitost uspořádání, Polymer nanocomposites (PNCs) hold a great promise as future lightweight functional materials processable by additive manufacturing technologies. However, their rapid deployment is hindered by their performance depending strongly on the nanoparticle (NP) spatial organization. Therefore, the ability to control the nanoparticle dispersion in the process of PNCs preparation is a crucial prerequisite for utilizing their potential in functional composites. This work investigates solution blending of PNCs in a model glass forming polymer matrix, a bulk processing technique of a tailored NP spatial organization controlled by structural and kinetic variables of the preparation protocol. The presented results describe the differences between nanoparticle induced changes on the rheological behavior of a polystyrene solution under large amplitude oscillation shear (LAOS). High-affinity OP-POSS NPs seem to interact with the PS at low filler loadings and form stiffened aggregates, whereas low-affinity OM-POSS NPs remained rather uninvolved in the polymer deformation at these conditions. Furthermore, an interest was focused on the impact of the blending solvent on the NP spatial arrangement in silica/PMMA and silica/PS nanocomposites, which has already been suggested as the controlling parameter of the solid-state structure. An emphasis was put on the qualitative differences between “poorly dispersed” NP arrays which, by combination of rheological assessment and structural analysis (TEM, USAXS), were identified as chain bound clusters and two types of aggregates, one of thermodynamic and the other of a kinetic origin, which are characterized by substantially distinct formation kinetics and mismatched properties compared to individually dispersed NPs and each other. The currently observed types of NP dispersion were quantitatively linked with their rheological properties during the solution blending step and the amount of polymer adsorption and depletion attraction. The results we

Polymerní nanokompozity (PNCs) mají slibnou budoucnost jako lehké funkční materiály zpracovatelné aditivními výrobními technologiemi. Jejich rychlému rozšíření však brání silná závislost jejich užitných vlastností na prostorovém uspořádání nanočástic (NP). Schopnost řídit disperzi nanočástic je tak klíčovým předpokladem pro jejich uplatnění ve funkčních kompozitech. Tato práce zkoumá přípravu polymerních nanokompozitů v modelové sklotvorné polymerní matrici roztokovou metodou, technikou schopnou vytvářet prostorové uspořádání nanočástic řízené strukturními a kinetickými parametry přípravného procesu. Prezentované výsledky popisují rozdíly mezi změnami rheologického chování roztoku polystyrenu při oscilačním smyku s vysokou amplitudou (LAOS) vyvolanými nanočásticemi. Výsledky vedou k závěru, že vysoce-afinní OP-POSS nanočástice při nízkých koncentracích dobře interagují s PS a tvoří tuhé agregáty, zatímco nízko-afinní OM-POSS nanočástice za těchto podmínek neovlivňují deformační chování polymerních řetězců. Dále byla pozornost zaměřena na vliv použitého rozpouštědla na uspořádání nanočástic v SiO2/PMMA a SiO2/PS nanokompozitech, který je v literatuře prezentován jako parametr řídící prostorové uspořádání nanočástic v pevném stavu. Důraz byl kladen na kvalitativní rozdíly mezi „špatně dispergovanými“ shluky nanočástic, které byly na základě rheologie a strukturální analýzy (TEM, USAXS) identifikovány jako polymerními řetězci vázané nanočásticové klastry a dva typy agregátů, jeden termodynamického a druhý kinetického původu. Jednotlivé druhy agregátů se vyznačují odlišnými kinetikami vzniku a rozdílnými vlastnostmi jak mezi sebou, tak v porovnání s dispergovanými nanočásticemi. Pozorované typy disperze nanočástic byly kvantitativně posouzeny podle svých rheologických vlastností během roztokové přípravy, podle kterých byla vyhodnocena míra adsorpce polymeru na povrch nanočástic a atrakce ve vypuzeném objemu. Výsledky byly porovnány s teorií PRISM. Důležitost uspořádání, Polymer nanocomposites (PNCs) hold a great promise as future lightweight functional materials processable by additive manufacturing technologies. However, their rapid deployment is hindered by their performance depending strongly on the nanoparticle (NP) spatial organization. Therefore, the ability to control the nanoparticle dispersion in the process of PNCs preparation is a crucial prerequisite for utilizing their potential in functional composites. This work investigates solution blending of PNCs in a model glass forming polymer matrix, a bulk processing technique of a tailored NP spatial organization controlled by structural and kinetic variables of the preparation protocol. The presented results describe the differences between nanoparticle induced changes on the rheological behavior of a polystyrene solution under large amplitude oscillation shear (LAOS). High-affinity OP-POSS NPs seem to interact with the PS at low filler loadings and form stiffened aggregates, whereas low-affinity OM-POSS NPs remained rather uninvolved in the polymer deformation at these conditions. Furthermore, an interest was focused on the impact of the blending solvent on the NP spatial arrangement in silica/PMMA and silica/PS nanocomposites, which has already been suggested as the controlling parameter of the solid-state structure. An emphasis was put on the qualitative differences between “poorly dispersed” NP arrays which, by combination of rheological assessment and structural analysis (TEM, USAXS), were identified as chain bound clusters and two types of aggregates, one of thermodynamic and the other of a kinetic origin, which are characterized by substantially distinct formation kinetics and mismatched properties compared to individually dispersed NPs and each other. The currently observed types of NP dispersion were quantitatively linked with their rheological properties during the solution blending step and the amount of polymer adsorption and depletion attraction. The results we