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We have developed a new strategy for the preparation of a light-responsive ionic liquid crystal (LC) that shows photo-switchable proton conduction. The ionic LC consists of a bowl-shaped calix[4]arene core ionically functionalized with azobenzene moieties. The non-covalent architectures were obtained by the formation of ionic salts between the carboxylic acid group of an azo-derivative and the terminal amine groups of a calixarene core. The presence of ionic salts results in a hierarchical self-assembly process that extends to the formation of a nanostructured lamellar LC arrangement (smectic A phase). In this LC phase, the ionic LC calixarene is able to display proton conductive properties, since the ionic nanosegregated areas (formed by the ionic pairs) generate the continuous channels that favor proton transport. The optical and photo-responsive properties were studied by UV-Vis spectroscopy, demonstrating that the azobenzene moieties of the ionic LC undergo reversible (E)-to-(Z) isomerization by irradiation with UV light. Interestingly, this (E)-to-(Z) photoisomerization results in a decrease of the proton conductivity values since the bent-shaped (Z)-isomer disrupts the lamellar LC phase. This isomerization process is totally reversible and leads to an ionic LC material with unique photo-switchable proton conductive properties.

We report a new family of liquid crystalline porphyrin-core dendrimers with coumarin units at the periphery of the dendrimer. These compounds have been prepared by copper-catalyzed azide–alkyne “click” cycloaddition (CuAAC). The mesomorphic properties have been investigated via polarized optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The peripheral coumarin units play a key role in the liquid crystal behavior, contributing to the appearance of discotic nematic mesophases with hole mobility values among the highest values reported for discotic liquid crystals (of the order of 1 cm2 V−1 s−1). It has also been demonstrated that excitation of the coumarin moieties leads to energy transfer (antenna effect) to the luminescent porphyrin core. Therefore, this strategy, which involves ‘click’ chemistry, has been proven to be a powerful and elegant synthetic tool for the preparation of optoelectronic materials based on complex dendritic architectures.

Background: Infertility is a huge reproductive health problem in developed countries. The aim was to understand the infertility experience of women who have undergone assisted reproduction technologies. Methods: Qualitative study using Grounded Theory. Through intentional sampling and theoretical sampling, 20 women who had undergone Assisted Reproduction Technologies in public hospitals and specialized private clinics in Spain were selected. Data were collected using semi-structured interviews and were analysed using the principles of Grounded Theory: initial coding and focused coding, memo writing, theoretical sampling and constant comparative method. Results: “Uncovering infertility: unveiling the unknown” is the core category that explains the process which women go through. Four subcategories emerged and describe the temporal process from seeking pregnancy to reception and coping with the infertility diagnosis: “Seeking for a vital desire: being mothers/fathers”, “Suspecting infertility: the absence of the natural”, “In search of a diagnosis: knowing and understanding the problem” and “The impact of diagnosis: a vital grief”. Conclusions: Uncovering infertility is a process that has an impact on the different areas of women’s lives. This process produces different emotions and feelings such as guilt, frustration, sadness or anger. This process could be easier if women have the support of their partner, their social environment and if they share their problem with women who have the same situation., Fundamentos: La infertilidad es uno de los grandes problemas de salud reproductiva en los países desarrollados. El objetivo de este estudio fue comprender la experiencia vivida de la infertilidad por mujeres que se han sometido a técnicas de reproducción asistida. Métodos: Estudio cualitativo de Teoría Fundamentada. Mediante muestreo intencional y muestreo teórico se seleccionaron 20 mujeres que habían sido sometidas a técnicas de reproducción asistida tanto en hospitales públicos como en clínicas privadas especializadas en España. La técnica de recogida de los datos fue la entrevista semiestructurada. El análisis siguió los procedimientos de la Teoría Fundamentada: codificación inicial y focalizada, escritura de memos analíticos, muestreo teórico y método de comparación constante. Resultados: “Descubrir la infertilidad: desvelar lo desconocido” es la categoría principal que explica el proceso que viven las mujeres. Emergieron cuatro subcategorías que describen el proceso temporal desde el inicio de la búsqueda de embarazo hasta la recepción y afrontamiento del diagnóstico de infertilidad: “Buscar un deseo vital: ser madres/ padres”, “Sospechar la infertilidad: la ausencia de lo natural”, “En busca de un diagnóstico: conocer y comprender el problema” y “El impacto del diagnóstico: un duelo vital”. Conclusiones: Descubrir la infertilidad es un proceso que afecta a los distintos ámbitos de la vida de las mujeres y en el que aparecen emociones y sentimientos como culpa, frustración, tristeza o rabia. Este proceso puede estar facilitado cuando se tiene el apoyo de su pareja, el entorno y se comparte el problema con mujeres que tienen su misma situación.

The design of efficient drug-delivery vehicles remains a big challenge in materials science. Herein, we describe a novel class of amphiphilic hybrid dendrimers that consist of a poly(amidoamine) (PAMAM) dendritic core functionalized with bisMPA dendrons bearing cholesterol and coumarin moieties. Their self-assembly behavior both in bulk and in water was investigated. All dendrimers exhibited smectic A or hexagonal columnar liquid crystal organizations, depending on the generation of the dendrimer. In water, these dendrimers self-assembled to form stable spherical micelles that could encapsulate Nile Red, a hydrophobic model compound. The cell viability in vitro of the micelles was studied in HeLa cell line, and proved to be non-toxic up to 72 h of incubation. Therefore, these spherical micelles allow the encapsulation of hydrophobic molecules, and at the same time provided fluorescent traceability due to the presence of coumarin units in their chemical structure, demonstrating the potential of these dendrimers as nanocarriers for drug-delivery applications.

Two novel series of ionic liquid crystal polymers that display proton conductive properties are presented here. These materials are based on linear (l-PEI) or branched (b-PEI) poly(ethyleneimine) functionalized with unsymmetrical oxadiazole carboxylic acids derived from 1,3,4-oxadiazole (1,3,4-OXAm) or 1,2,4-oxadiazole (1,2,4-OXAm). The subscript “m” indicates the length of the spacer between the rigid moiety and the carboxyl group, namely m = 4 and 10. The occurrence of proton transfer from the carboxylic acid to the amine groups was confirmed by FTIR and NMR measurements. The liquid crystalline properties were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and X-ray diffraction (XRD). All ionic complexes displayed enantiotropic smectic A mesophases and in the case of the l-PEI derivatives a nematic phase was also observed at high temperatures. All investigated derivatives presented good proton conductivity values as determined by electrochemical impedance spectroscopy (EIS). Therefore, these ionic LC hyperbranched polymers represent an effective approach for the preparation of proton-transporting polymeric materials with potential applications in electrochemical devices.

We have prepared nanoporous polymers from columnar hexagonal hydrogen-bonded complexes, whose order is fixed by coumarin photoinduced [2 + 2] cycloaddition (photodimerization). Two different hydrogen-bonded complexes were used and consisted of a melamine (M) or tris(triazolyl)triazine (T) derivative acting as central templates and three peripheral carboxylic acids containing coumarin units. These coumarin units were employed for the cross-linking process by photodimerization in order to fix the LC arrangement. Template removal leads to the formation of self-standing nanoporous polymers keeping the columnar hexagonal order. Two nanoporous polymers with different pore diameters were obtained depending on size of the utilized template. These polymers with carboxylic acids at the pore surface demonstrate the ability to selectively adsorb certain molecules depending on their size. Moreover, after base treatment of the nanoporous polymers, they are able to adsorb cationic dyes over anionic and larger cations, demonstrating size- and charge-selective adsorption.

The self-assembly of liquid crystals (LCs) is an important method to control the organization of single molecules into periodically nanostructured phases that have found applications in organic electronics. Herein, we report a new family of LC porphyrin-core dendrimers bearing carbazole moieties at the periphery of the dendrimer. These compounds are synthetic light-harvesting antennas, which exhibit intramolecular energy transfer from the carbazole moieties to the central porphyrin core. We also demonstrate that it is possible to deposit spherical polymeric nanoparticles on ITO electrodes via electrochemical crosslinking of peripheral carbazole units. Moreover, the porphyrin-core dendrimers exhibit discotic nematic phases with excellent film-forming properties and a strong tendency towards defect-free homeotropic alignment. Charge mobility studies reveal promising semiconductor properties with high hole mobility values. Therefore, such carbazole-containing LC dendrimers exhibit a unique combination of interesting properties, opening the way for the preparation of new optoelectronic materials.

Liquid crystal macrocycles (LCMs) combine the unique properties of liquid crystals with those associated with macrocyclic compounds—shape persistence and the capability of hosting small molecules. Herein, we investigate the grafting of coumarin-containing promesogenic moieties to pillar[5]arene as a strategy to obtain multifunctional LCMs. Pillar[5]arenes containing 10 and 30 coumarin units are glassy materials with nematic mesomorphism. Moreover, the coumarin moieties afford the pillar[5]arene derivatives with enhanced film-forming and photoresponsive properties. Photodimerization of the coumarin moieties results in cross-linked polymer networks, which can be used as alignment layers. Therefore, liquid-crystal coumarin-containing pillar[5]arenes represent a significant addition to the family of LCMs and may become useful for the development of engineered, hierarchical structures and materials.

The design of efficient drug-delivery vehicles remains a big challenge in materials science. Herein, we describe a novel class of amphiphilic hybrid dendrimers that consist of a poly(amidoamine) (PAMAM) dendritic core functionalized with bisMPA dendrons bearing cholesterol and coumarin moieties. Their self-assembly behavior both in bulk and in water was investigated. All dendrimers exhibited smectic A or hexagonal columnar liquid crystal organizations, depending on the generation of the dendrimer. In water, these dendrimers self-assembled to form stable spherical micelles that could encapsulate Nile Red, a hydrophobic model compound. The cell viability in vitro of the micelles was studied in HeLa cell line, and proved to be non-toxic up to 72 h of incubation. Therefore, these spherical micelles allow the encapsulation of hydrophobic molecules, and at the same time provided fluorescent traceability due to the presence of coumarin units in their chemical structure, demonstrating the potential of these dendrimers as nanocarriers for drug-delivery applications.

We have prepared nanoporous polymers from columnar hexagonal hydrogen-bonded complexes, whose order is fixed by coumarin photoinduced [2 + 2] cycloaddition (photodimerization). Two different hydrogen-bonded complexes were used and consisted of a melamine (M) or tris(triazolyl)triazine (T) derivative acting as central templates and three peripheral carboxylic acids containing coumarin units. These coumarin units were employed for the cross-linking process by photodimerization in order to fix the LC arrangement. Template removal leads to the formation of self-standing nanoporous polymers keeping the columnar hexagonal order. Two nanoporous polymers with different pore diameters were obtained depending on size of the utilized template. These polymers with carboxylic acids at the pore surface demonstrate the ability to selectively adsorb certain molecules depending on their size. Moreover, after base treatment of the nanoporous polymers, they are able to adsorb cationic dyes over anionic and larger cations, demonstrating size- and charge-selective adsorption.

Los dendrímeros constituyen en la actualidad un área de extraordinario interés en la investigación de materiales funcionales. El uso de los cristales líquidos como agentes capaces de promover la ordenación de las unidades activas presentes dentro de la estructura dendrítica puede dar lugar a la creación de un nuevo tipo de materiales orgánicos con aplicaciones tanto en Ciencia de Materiales como en Biomedicina. El objetivo principal de esta tesis ha sido la obtención de nuevos materiales funcionales a partir de dendrímeros cristales líquidos para su aplicación como semiconductores orgánicos, para la obtención de materiales conductores de protones, para la preparación de membranas nanoporosas y para aplicaciones biomédicas.

In this work, we have successfully examined for the first time the use of ionic dendrimers as building blocks for the preparation of 1D and 2D proton conductive materials. For this purpose, a new family of liquid crystalline dendrimers has been synthesized by ionic self-assembly of poly(amidoamine) (PAMAM) dendrimers bearing 4, 8, 16, 32 or 64 NH2 terminal groups and a coumarin-containing bifunctional dendron. The noncovalent architectures were obtained by the formation of ionic salts between the carboxylic acid group of the dendron and the terminal amine groups of the PAMAM dendrimer. The liquid crystal properties have been investigated by polarized optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). All the compounds exhibited mesogenic behavior with smectic A or hexagonal columnar mesophases depending on the generation of the dendrimer. Coumarin photodimerization was used as a crosslinking reaction to obtain liquid crystalline polymer networks. All the materials showed good proton conductive properties as the LC arrangement leads to the presence of ionic nanosegregated areas (formed by the ion pairs) that favor proton conduction.

In the early eighties, Lin Lei proposed the concept of liquid crystals formed by bowl-like molecules. Thus, if calixarene cores (bowlic-like molecules) are functionalized with promesogenic units they could self-organize into bowlic liquid crystalline mesophases. Liquid crystal (LC) calixarenes represent an attractive option for the design of functional materials that combine the inherent properties of calixarenes with the anisotropic properties provided by the LC state, thus achieving the preparation of materials with a variety of new applications. Here we described the synthesis and mesomorphic properties of a new family of liquid crystals calix[4]arenes incorporating Schiff bases in the periphery that exhibit Smectic A or Nematic mesophase. XRD studies revealed interesting structural details concerning the packing of these compounds in their mesophases. On the basis of the experimental results, some supramolecular models have been proposed (Figure 1). The three calix[4]arene derivatives were subjected to metal complexation with different alkali, alkaline earth and transition metals, a novel and effective off-on-off type dihydrophosphate derivative chemosensor has been developed based on Zn-complexes.

The synthesis and liquid crystalline behavior of new calixarene Schiff base derivatives are reported. The materials were obtained by reaction of a tetraaminocalix[4]arene derivative with three aldehydes as mesogenic promotor moieties: 4‐(4′‐decyloxybenzoyloxy)benzaldehyde (A), 4‐(4′‐decyloxybenzoyloxy)salicylaldehyde (B) and 4‐(3′,4′‐didecyloxybenzoyloxy)salicylaldehyde (C). All of the compounds exhibit liquid crystalline properties and these were studied by optical microscopy, DSC and X‐ray diffraction. The relationship between the structure and the mesomorphic behavior of the compounds is discussed. The binding recognition and selectivity towards cations have been studied by absorption and fluorescence spectroscopy.

We report a new family of multifunctional liquid-crystalline porphyrin-core dendrimers that have coumarin functional groups around the porphyrin core. Porphyrin metalation strongly affects the photophysical properties, and therefore Zn and Cu derivatives have also been prepared. All the synthesized dendrimers form a nematic discotic mesophase. Their high tendency for homeotropic alignment makes these dendrimers excellent candidates for device applications, owing to their easy processability, spontaneous alignment between electrodes, and self-healing of defects because of their dynamic nature. The charge mobility values of these materials are the highest ever reported for a nematic discotic phase. Moreover, these values are similar to the highest values reported for ordered columnar mesophases, and this shows that a supramolecular organization in columns is not necessary to achieve high charge mobility.

The increment of world population increases the need of improving feed efficiency traits of livestock. However, the molecular mechanisms underlying different feed efficiency traits and their regulation by nutrition remain poorly understood. The present study was designed to identify plasmatic metabolites and metabolic pathways of fattening merino lambs caused by milk restriction during the suckling period. Forty male lambs were assigned randomly to two groups (n=20 per group) with different suckling regime: ADL (lambs were kept continuously with their dams) and RES (lambs were allowed to suck for 15 hours). When they reached 15 kg of live body weight (LBW), all the animals were offered the same complete pelleted diet at a restricted level (40 g DM/kg LBW). All the lambs were slaughtered with 27 kg of LBW and 12 representative animals from each group were selected for the analysis. Metabolomic analysis was carried out on a mass spectrometer coupled to an UHPLC chromatographic system (UHPLC/QTOF-MS). According to the data obtained in the present study, a restricted milk intake level during the suckling period of merino lambs promoted long term effects on efficiency traits and metabolic profile which might have modified fatty acids metabolism during the fattening period.