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El grupo de investigación de ingeniería textil (TECTEX) INTEXTER y del Departamento de Ciencia e Ingeniería de Materiales de la Universitat Politècnica de Catalunya tiene como principal objetivo el desarrollo y optimización de nuevos materiales, procesos y tecnologías de la cadena de valor de la industria textil (desde la producción y caracterización de fibras y tejidos, procesos de tintura y acabado, hasta productos textiles). La finalidad de la actividad de nuestro grupo de investigación es reducir los impactos ambientales, aumentar la circularidad y optimizar los materiales, procesos y tecnologías textiles, así como desarrollar soluciones de alto valor añadido. Todo ello para contribuir a la creación de un sector textil más sostenible y competitivo. En particular, la investigación que llevamos a cabo en TECTEX se centra en contribuir a resolver los retos globales y las necesidades de competitividad industrial europea relacionadas con la transición ecológica y la transición digital, así como con el desarrollo de nuevas soluciones de alto valor añadido enfocadas principalmente al desarrollo de dispositivos y sistemas para aplicaciones biomédicas. En este artículo se presentarán los principales proyectos que actualmente estamos liderando desde nuestro grupo de investigación, como son los proyectos relacionados con la obtención de fibras naturales a partir de residuos agrícolas (HEMPQUAL), la obtención de colorantes naturales a partir de residuos agrícolas (OLIWASTEX), el reciclaje de residuos textiles por métodos mecánicos (RECYWASTEX), el desarrollo de materiales compuestos de cemento reforzados con fibras y estructuras textiles (RECYBUILDMAT), el electrohilado para aplicaciones biomédicas (ONCOFIBRAS y la aplicación del blockchain y trazabilidad a la industria textil (TRICK), Los proyectos presentados en este artículo han recibido financiación de las siguientes entidades: Gobierno de España, Agencia estatal de investigación: PID2019-108067RB-I00/ AEI/10.13039/501100011033 (proyecto RECYBUILDMAT) Gobierno de España y Unión Europea: TED2021-130611B-I00 (proyecto RECYWASTEX), financiado por MCIN/AEI/10.13039/501100011033 y por la Unión Europea “NextGenerationEU”/PRTR Generalitat de Catalunya: ACE034/21/000053 (proyecto ONCOFIBRAS); 2021PROD00074 (proyecto OLIWASTEX), 2021PROD00079 (proyecto HEMPQUAL) Unión Europea: H2020-958352-TRICK (proyecto TRICK), Postprint (published version)

(English) Air jet spinning is an emerging technology, already well established in the textile market. The commercial success increased over the last decades and intensified the research and innovation approach in the field of air jet spinning machines. The requirements for establishing air spun yarn in the textile market include high yarn quality, high production speeds and high material yield during the process. The concept and the quality of the integrated drafting system of an air jet spinning machine is one of the responsible parts to influence the named requirements. Moreover, the drafting system directly influences the regularity of fibre motion during the transportation to the spinning nozzle. In this case, the fibres need to deal with challenges like highly increasing velocities of the roller pairs and resulting air turbulences which cause misaligned fibres at the main draft zone. False twist is a welt-known principle in the textile process technology. False twist is used to stabilize the spinning stability, to create special effects on yarn structure or to impact the spinning process in general. Based on the principles of false twist, the aim of this work is to use the characteristics of false twist in the drafting system of an air jet spinning machine to improve the fibre motion during drafting. The PhD thesis presents the use of the principles of false twist implementation into the drafting system to influence the fibre control during high speed drafting for air jet spinning machines. Therefore, two prototypes were developed, tested, and evaluated by their impact for the fibre motion through the drafting system. A dynamic false twist device which can insert false twist individually set by torque and velocity into the drafted fibre bundle is used. Moreover, a video analysis tool was developed to measure the fibre motion. In the theoretical part, a control analysis of false twist integration into a fibre assembly was developed, which simplified the predicti, (Español) La hilatura por chorro de aire o neumática es una tecnología emergente, actualmente bien establecida en el mercado textil. Su éxito comercial ha aumentado en las últimas décadas y ha intensificado el enfoque de la investigación y la innovación en el campo de las máquinas de hilar por aire. Los requisitos para consolidar la hilatura por aire en el mercado textil incluyen una alta calidad del hilo, altas velocidades de producción y un alto rendimiento del material durante el proceso. El concepto y la calidad del tren de estiraje integrado de una máquina de hilar por chorro de aire es uno de los aspectos más influyentes en los requisitos mencionados. Además, el sistema de estiraje influye directamente en la regularidad del movimiento de las fibras durante el transporte a la boquilla de hilatura de la tobera neumática. En este caso, las fibras tienen que enfrentarse a inconvenientes como el aumento de la velocidad de los pares de rodillos y las turbulencias de aire resultantes, que provocan la desalineación de las fibras en la zona de estiraje principal. La falsa torsión es un principio bien conocido en la tecnología del proceso textil. Se utiliza para estabilizar la formación del hilo, para crear efectos especiales en la estructura del hilo o para influir en el proceso de hilatura en general. Basándose en los principios de la falsa torsión, el objetivo de este trabajo es utilizar las características de la falsa torsión en el sistema de estiraje de una máquina de hilar por chorro de aire para mejorar el movimiento y recorrido de las fibras durante el estiraje. Esta tesis doctoral presenta el uso de los principios de la falsa torsión en el sistema de estiraje para mejorar el control de la fibra durante el estiraje de alta velocidad para máquinas de hilatura neumática. Por lo tanto, se ha desarrollado, probado y evaluado el impacto en el movimiento de la fibra en su recorrido durante a través del sistema de estiraje de dos prototipos funcionales. Además, se ha d, Postprint (published version)

Durante las últimas décadas, la administración de medicamentos a través de la piel ha evolucionado significativamente. En 1981, se patentaron parches que liberaban escopolamina para tratar mareos y náuseas. Este método, conocido como sistema de administración de fármacos (DDS), combina materiales poliméricos y farmacéuticos para administrar sustancias de manera menos invasiva. Los apósitos, utilizados desde los albores de la medicina, han evolucionado hacia versiones sintéticas multifuncionales. Estos apósitos buscan prevenir infecciones y fomentar la cicatrización. Las membranas nanofibrosas creadas mediante electrospinning son cruciales en este avance, permitiendo el transporte de fármacos en diversas patologías, como el cáncer y la regeneración ósea. El ácido poli-láctico (PLA), un polímero biodegradable, se emplea para formar membranas poliméricas que actúan como vehículos de fármacos. Estas membranas, llamadas estructuras sándwich, desempeñan un papel vital en la administración controlada de medicamentos. Las membranas nanofibrosas también sirven como base para andamios poliméricos, esenciales en la ingeniería de tejidos y que pueden ser reforzados con partículas electroactivas como la lanolina, con propiedades antibacterianas. El proyecto se centra en desarrollar estructuras sintéticas similares a la piel humana en términos de permeabilidad, capas, lubricación y porosidad. Estas estructuras podrían convertirse en una vía de transporte para fármacos microencapsulados en el futuro. Se obtuvieron cuatro membranas híbridas en cuya estructura llevaba intrínseca la lanolina, con distintas características de hidrofobicidad e hidrofilia y, a través de análisis potenciométrico y medida del ángulo de contacto, una de ellas demostró tener un comportamiento parecido a la piel humana en cuanto a afinidad por el agua, porosidad y transpirabilidad

The manipulation, assembly, and control of matter at the nanometer scale enable the fabrication of nanomaterials that could revolutionize the industry and impact our society. Various bacterial species such as K. xylinus or K. rhaeticus already manufacture nanocellulose directly at the nanometric scale. The resulting cellulose, called bacterial nanocellulose (BNC), is secreted in its purest form, with high crystallinity (up to 90%) and a high degree of polymerization. This bottomup approach to production comes with many advantages over traditional wood-based nanocellulose. In addition to growing without lignin, hemicellulose, or pectin, which eliminates the extraction step, BNC also does not need any mechanical separation or hydrolysis processes to become nano. Moreover, the formation of cellulosic microfibrils occurring during biosynthesis is influenced by many factors such as culture medium, temperature, pH, agitation, and oxygen level, which can be modified according to the desired properties. Today, there are some challenges that slow down the entry of this material into the industrial scene. The first is the optimization of production yield and cost of the raw materials used for cultivation. The second is its hard processability such as the dissolution process, which limits its scope of applications. In this study, three experimental parts have been conducted to measure the issues holding back BNC from developing on an industrial scale. The first part focuses on the parameters influencing the productivity and the quality of the BNC. Each parameter is analyzed by calculating the production yield and the water loss of the bacterial nanocellulose. The highest production yield of 12.85 g/L was obtained over a period of 20 days in a 0.5% w/v green tea and 10% w/v sucrosebased culture media. However, coffee showed impressive results with a yield of 7.08 g/L over a culture of 7 days. 32°C was found to be the optimal growing temperature. A pH set at 2.9 gave a higher yi

The scientific and medical communities are showing a growing interest in tissue engineering as a means to solve issues regarding donor tissues, wound healing and drug delivery systems. Nanofibers are gaining quite a lot of relevance in this pursuit as their excellent mechanical properties and morphological similarities to the extracellular matrix of skin make them an ideal component. This project has explored how closely hybrid structures created with a combination of PLA nanofiber membranes and lanolin could imitate the human skin, with a special emphasis on achieving a similar permeability. Tests were done with an Optical Tensiometer, Electro Kinetic Analyzer and a Franz Cell. The results have shown that a perfect sandwich hybrid structure, alternating a PLA nanofiber membrane with a layer of lanolin, had a transpirability of 5,63 g/(m2 ·h), which is within the range of human skin transpirability values; 2,3 to 44 g/(m2 ·h)

This project proposes a set of requirements for the implementation of a blockchain based traceability solution for the textile industry to support the transition from linear to circular. The study includes the Scenarios, the User Needs and the Use Cases required to develop a software platform and their corresponding services. The textile industry is one of the most pollutant industries in the world, causing irreversible impacts to the environment and society. The new market trends, policies and conscious consumers demand for a more sustainable, collaborative and transparent model. Innovation, digitalization and new technologies can help on the transition from linear to circular to overcome the complexity and opaqueness of the textile supply chain. Specifically, blockchain based solutions that can improve transparency and traceability due to their inherent functioning. A collaborative methodology has been designed in order to get the all perspectives for the supply chain actors and from all the stakeholders interested and relevant for the solution. Consisting on set of user experience focused interviews, questionnaires and workshops, the necessary data for the platform development has been collected. Data has been compiled on a set of scenarios, user needs and project implementation possible barriers. The scenarios are based on the common interests of the different stakeholders, and they describe the desired solution, reflecting the complexity of the solution and of the sector. The proposed Use Cases for software implementation contemplate the different types of usage of the traceability solution. The Use Cases are complemented with the product vision for the platform which broads the description of the expected solution from the user perspective. In order to face the different barriers and challenges, a de-risking proposal is also proposed. This project gives a whole framework for implementing a traceability solution accounting the challenges and proposes detailed s

En aquest projecte de fi de grau s’estudiarà el disseny d’un prototip per realitzar assajos de tracció de membranes obtingudes mitjançant el mètode d’electrospinning. Aquest prototip de mida reduïda s’ha d’utilitzar en una sala blanca de classe ISO 7 en condicions de protecció contra agents biològics, ja que estan dopades amb medicaments citotòxics.

This paper addresses the major concern which component porosity represents in Vacuum Infusion (VI) manufacturing due to resin gelation at pressures close to absolute vacuum. Degassing is a fundamental step to minimize or even avoid resin outgassing and enhance dissolution of voids created during preform impregnation. The efficacy of different degassing procedures based on vacuum degassing, and assisted by adding a nucleation medium, High Speed (HS) resin stirring and/or later pressurization during different time intervals have been analyzed in terms of final void content is studied. Through a rigorous and careful design of the manufacturing process, outgassing effects on final void content were isolated from the rest of porosity causes and specimens with two clearly identifiable regions in terms of porosity were manufactured to facilitate its analysis. Maximum void content was kept under 4% and porous area size was reduced by 72% with respect to conventional vacuum degassing when resin was stirred at HS; therefore, highlighting the importance of enhancing bubble formation during degassing, The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The research was financially supported by Escola Superior d’Enginyeries Industrial, Aeroespacial i Audiovisual de Terrassa (ESEIAAT), Universitat Politecnica de Catalunya (UPC) and SENER Ingenieria y Sistema, Postprint (published version)

Background: RPS local recurrence after radical surgery (SX) is frequent and a major cause of death. Locally delivered CHT by a biocompatible and biodegradable implant matrix (CEB-01) loaded with SN-38 and placed in the surgical bed during SX may increase local control and survival in RPS patients with reduced systemic toxicity. Methods: This is a multicentre, open label, first-in-human phase 1 trial comprising a dose-escalation phase (3 cohorts with total SN-38 doses of 9, 18 and 36 mg respectively), followed by an expansion cohort at the recommended phase 2 dose (RP2D). Recurrent or locally advanced RPS patients candidates for local surgery, with no option of systemic treatment, ECOG < 2, life expectancy > 6 months, and normal organ function are eligible. Primary objective is to determine RP2D, defined as the dose level at which less than 33% of patients present dose limiting toxicity (DLT) in a minimum of 6 at-risk patients during the first two weeks after SX. DLT is defined as any Grade =3 toxicity. Secondary objectives include safety, time to recurrence, biomarkers, pharmacokinetics (PK) and quality of life (QoL). Here we report preliminary safety, efficacy, and PK data for the initial patients enrolled. Results: First cohort of 9 mg SN-38 was completed in february 2021, with the inclusion of three patients with dedifferentiated liposarcoma, (grade 2-3) Patients were male, age 65 to 74, with ECOG of 0-1. Optimal SX were performed for recurrent/metastatic disease (2 patients) or locally advanced disease (1 patient) with complete (R0) and optimal (R1) outcomes. There were no surgical complications attributed to the SN-38 treatment. One patient suffered from grade 2 (Dindo Clavien classification) intestinal subocclusion due to SX complication resolved with medical treatment at day 5. Frequency and severity of adverse events (AE) was low. All the patients presented transitory abdominal discomfort and seroma. AEs consisted of one catheter infection and one hypomagnes, Postprint (published version)

The textile dyeing produces a large volume of wastewater with high salinity and deep colouration. Residual dyes are generally not removed in conventional wastewater treatments and therefore specific treatments are required to remove colour. Sometimes, textile mills are not able to accomplish water discharge regulations as salts cannot be removed in the common wastewater treatments. To face both problems, salinity and colour of effluents, a new system has been designed based on a coupled electrochemical and UV process (EC-UV). It is a fast and simple treatment that enables the effluents colour removal. In addition, the wastewater salinity can also be reduced through the reuse of the treated effluents in new productive processes. The treatment is particularly efficient in the reactive dyeing process, although it can also be used for direct effluents. The implementation of this new system in the textile industry achieves significant benefits. The reuse of effluents containing high amount of salts implies lower consumption of water and salt in the dyeing process, and the removal of colour improves the yield of wastewater treatment plants with less consumption of chemicals. Finally, the reduction of wastewater salinity is also an additional economic and environmental benefit of the treatment, which results in lower wastewater taxes and improvement of the aquatic ecosystems, This research was co-funded by the European Commission within the CIP Eco-Innovation initiative of the Competitiveness and Innovation Framework Programme, CIP: ECUVal project (ECO/13/630452). For more information: www.ecuval.eu, Postprint (author's final draft)

One of the great advantages of electrospun fibers is the large tridimensional area produced, capable of storing any type of material. The aim of our investigation is to study the electrospinning technique to produce polymer membranes for drug delivery applications, given their large surface area and ability to transport a bioactive compound. A mathematical modeling of the delivery system kinetics was also studied to find the mechanism that controls the releasing process. Results showed that electrospinning could provide regular and smooth membranes suitable for drug delivery processes. The choice of a proper solvent for this process was an important parameter analyzed, because it determined whether fibers were capable of forming, as well as influencing fiber porosity. The mathematical modeling also proved that thicker PLLA membranes exhibited a Fickian diffusion behavior during the drug transport, presenting better control in drug delivery processes, The authors are grateful to CAPES for financial support, Postprint (published version)

La falta de material de protección frente al COVID-19 afecta de forma alarmante a los profesionales de la salud, pero también a los cuidadores de personas mayores, profesionales de la limpieza, alimentación, transporte, fuerzas del orden, etc. Los equipos de protección individual (EPI) que deben utilizarse para COVID19 son, principalmente, las mascarillas, las gafas, los guantes y la ropa de protección, siendo esta última en la que nos vamos a centrar en este artículo, Postprint (author's final draft)

The world of technical textiles is present every day in more sectors. In the work presented, a new facet of textile materials has been shown, textiles as a drug excipient and functional matrix. It is known that electro-spinning technology has opened up a range of possibilities in the field of medical textiles. However, the environment and the requirements of the pharmaceutical sector make the implementation of any new product a long and expensive job. This work is part of a project to develop a new medicine for both adult and paediatric cancer use. The drug that is developed uses as excipient and support matrix a non-woven formed with nanofibers made by the electro-spinning technique. During the nonwoven formation process, the active ingredient (API) is integrated into the structure. In this way, a very effective drug is produced for its intended use. The present work focuses on finding solutions that help the development of this drug by adapting the textile production of nanofibers to the level of quality required for the production of a drug intended to be implanted inside a person. For this reason, a search has been made on the current state of the art of nanofiber production technologies. This has been done in order to ensure the production and scaling process in a future implementation in the development of the product at the commercial level. From a development point of view, the mode of deposition of the nanofiber beam in the collector has been analysed. Theoretical concepts of a textile nature have been developed such as fibre count, deposition rate, total draw and polymer adapted to the electro-spinning technique. With these developments, new studies may be carried out that include these variables to gain an in-depth understanding of their influence on the structure of fibres and their properties, as is the case with fibres produced by conventional textile filament extrusion techniques. Moreover, an analysis was carried out with its corresponding validation, El mundo de los textiles de técnicos está presente cada día en más sectores. En el trabajo presentado se ha mostrado una nueva faceta de los materiales textiles: los textiles como excipiente de medicamento. Es conocido que la tecnología de electrohilatura ha abierto un abanico de posibilidades en el sector de los textiles de uso médico. Sin embargo, el entorno y los requisitos del sector farmacéutico hacen que la implementación de cualquier nuevo producto sea un trabajo largo y costoso. Este trabajo se enmarca dentro de un proyecto de desarrollo de un nuevo medicamento de uso oncológico tanto adulto como pediátrico. El fármaco que se desarrolla usa como excipiente un no tejido formado con nanofibras elaboradas por la técnica de electrohilatura. Durante el proceso de formación del no tejido se integra el principio activo (API) en la estructura. De este modo, se produce un fármaco muy eficaz para el uso al que va destinado. El presente trabajo se centra en buscar soluciones que ayuden al desarrollo de este fármaco mediante la adecuación de la producción textil de nanofibras al nivel de calidad requerido para la producción de un fármaco destinado a ser implantado dentro de una persona. Por este motivo, se ha realizado una búsqueda en el estado actual de la técnica de las tecnologías de producción de nanofibras, con objeto de asegurar el proceso de producción y escalado en una futura implementación en el desarrollo del producto a nivel de comercial. Bajo un punto de vista de desarrollo, se ha analizado el modo de deposición del haz de nanofibras en el colector. En este apartado se han desarrollado conceptos teóricos de naturaleza textil como son: título de fibra, velocidad de deposición, estiraje total y de polímero adaptados a la técnica de electrohilatura. Con estos desarrollos se podrán realizar nuevos estudios que incluyan estas variables para conocer en profundidad la influencia de estos en la estructura de las fibras y sus propiedades, tal y como sucede con las fi, Postprint (published version)

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En este artículo se presenta un breve resumen de las tendencias observadas en los campos de hilatura y no tejidos en la feria ITMA 2019, celebrada en Barcelona. Se comenta de forma general donde se han concentrado los esfuerzos de innovación y desarrollo del sector y de forma particular las novedades más representativas mostradas por algunos de los principales fabricantes, Postprint (published version)

Descripción de un sistema para almacenar el perfil morfológico del usuario y aplicarlo después en comercio online de moda o cualquier sector cuyos productos o servicios dependan de este perfil. Financiado con el proyecto Morpheos del programa Horizon 2020 de la EU., Postprint (published version)

Delivery of chemotherapy in the surgical bed has shown preclinical activity to control cancer progression upon subtotal resection of pediatric solid tumors, but whether this new treatment is safe for tumor-adjacent healthy tissues remains unknown. Here, Wistar rats are used to study the anatomic and functional impact of electrospun nano¿ber matrices eluting SN-38—a potent chemotherapeutic agent—on several body sites where pediatric tumors such as neuroblastoma, Ewing sarcoma, and rhabdomyosarcoma arise. Blank and SN-38-loaded matrices embracing the femoral neurovascular bundle or in direct contact with abdominal viscera (liver, kidney, urinary bladder, intestine, and uterus) are placed. Foreign body tissue reaction to the implants is observed though no histologic damage in any tissue/organ. Skin healing is normal. Tissue reaction is similar for SN-38-loaded and blank matrices, with the exception of the hepatic capsule that is thicker for the former although within the limits consistent with mild foreign body reaction. Tissue and organ function is completely conserved after local treatments, as assessed by the rotarod test (forelimb function), hematologic tests (liver and renal function), and control of clinical signs. Overall, these ¿ndings support the clinical translation of SN-38-loaded nano¿ber matrices to improve local control strategies of surgically resected tumors, Postprint (author's final draft)

This paper addresses the design, simulation, manufacturing and experimental test of textile dipole antennas based on advanced embroidery techniques. The proposed dipoles are intended to operate at the 2.45 GHz industrial scientific and medical radio band for wireless body area network applications. Two medium stitch density embroidery patterns have been studied: satin fill and contour fill, implemented according to the ISO 4915:1991 301 stitch type standard. The impact and viability of these embroidery techniques over the dipole performance in cotton and felt textile substrates are reported. Test results confirm notable antenna parameter results in terms of return loss, radiation pattern, realized gain and efficiency. In particular, contour pattern has been revealed as the best embroidery manufacturing technique in terms of quality factor and losses, whereas the satin pattern fits with a higher degree of accuracy the resonance frequency of the antenna., Peer Reviewed, Postprint (published version)

One of the great advantages of electrospun fibers is the large tridimensional area produced, capable of storing any type of material. The aim of our investigation is to study the electrospinning technique to produce polymer membranes for drug delivery applications, given their large surface area and ability to transport a bioactive compound. A mathematical modeling of the delivery system kinetics was also studied to find the mechanism that controls the releasing process. Results showed that electrospinning could provide regular and smooth membranes suitable for drug delivery processes. The mathematical modeling also proved that thicker PLLA membranes exhibited a Fickian diffusion behavior during the drug transport, presenting better control in drug delivery processes, Postprint (published version)

The feasibility of using Phosphate Buffer Saline (PBS)/ethanol mixtures as a benign solvent to electrospin three types of gelatin was studied. Gelatins with different chemical properties, such as Bloom, were selected and the effect of the gelatin nature and its concentration on the electrospinnability of the dope solution and on the fiber diameter of the electrospun mats were studied. Viscosity of the gelatin solution, which follows a power law relationship with the gelatin concentration, was found to significantly influence the morphology of the mats and the fiber diameter. It was demonstrated that the PBS/ethanol solvent interacted with the gelatins as a good solvent with a Flory exponent of 0.65. In addition, the effect of the solvent composition on the fiber formation process was evaluated corroborating that the ionic strength of the medium and the PBS/ethanol ratio significantly affected the morphology and the diameter of the electrospun fibers. Chemical structure and thermal stability of the electrospun gelatin mats were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). Finally, cytotoxicity of the electrospun mats was analyzed by the Alamar Blue assay, using human foreskin fibroblasts (BJ-5ta), resulting in a high cell viability (80-90%) regardless the type of gelatin, Postprint (author's final draft)

Gelatin fibers were prepared by electrospinning of gelatin/acetic acid/water ternary mixtures with the aim of studying the feasibility of fabricating gelatin nanofiber mats at room temperature using an alternative benign solvent by significantly reducing the acetic acid concentration. The results showed that gelatin nanofibers can be optimally electrospun with low acetic acid concentration (25% v/v) combined with gelatin concentrations higher than 300 mg/ml. Both gelatin solutions and electrospun gelatin mats (prepared with different acetic acid aqueous solutions) were analyzed by FTIR and DSC techniques in order to determine the chemical and structure changes of the polymer. The electrospun gelatin mats fabricated from solutions with low acetic acid content showed some advantages as the maintenance of the decomposition temperature of the pure gelatin (~230ºC) and the reduction of the acid content on electrospun mats, which allowed to reach a cell viability upper than 90% (analyzed by cell viability test using human dermal fibroblast and embryonic kidney cells). This study has also analyzed the influence of gelatin and acetic acid concentration both on the solution viscosity and the electrospun fiber diameter, obtaining a clear relationship between these parameters, Postprint (author’s final draft)

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In addition to surgery, local tumor control in pediatric oncology requires new treatments as an alternative to radiotherapy. SN-38 is an anticancer drug with proved activity against several pediatric solid tumors including neuroblastoma, rhabdomyosarcoma and Ewing sarcoma. Taking advantage of the extremely low aqueous solubility of SN-38, we have developed a novel drug delivery system (DDS) consisting of matrices made of poly(lactic acid) electrospun polymer nanofibers loaded with SN-38 microcrystals for local release in difficult-to-treat pediatric solid tumors. To model the clinical scenario, we conducted extensive preclinical experiments to characterize the biodistribution of the released SN-38 using microdialysis sampling in vivo. We observed that the drug achieves high concentrations in the virtual space of the surgical bed and penetrates a maximum distance of 2 mm within the tumor bulk. Subsequently, we developed a model of subtotal tumor resection in clinically relevant pediatric patient-derived xenografts and used such models to provide evidence of the activity of the SN-38 DDS to inhibit tumor regrowth. We propose that this novel DDS could represent a potential future strategy to avoid harmful radiation therapy as a primary tumor control together with surgery, In addition to surgery, local tumor control in pediatric oncology requires new treatments as an alternative to radiotherapy. SN-38 is an anticancer drug with proved activity against several pediatric solid tumors including neuroblastoma, rhabdomyosarcoma and Ewing sarcoma. Taking advantage of the extremely low aqueous solubility of SN-38, we have developed a novel drug delivery system (DDS) consisting of matrices made of poly(lactic acid) electrospun polymer nanofibers loaded with SN-38 microcrystals for local release in difficult-to-treat pediatric solid tumors. To model the clinical scenario, we conducted extensive preclinical experiments to characterize the biodistribution of the released SN-38 using microdialysis sampling in vivo. We observed that the drug achieves high concentrations in the virtual space of the surgical bed and penetrates a maximum distance of 2 mm within the tumor bulk. Subsequently, we developed a model of subtotal tumor resection in clinically relevant pediatric patient-derived xenografts and used such models to provide evidence of the activity of the SN-38 DDS to inhibit tumor regrowth. We propose that this novel DDS could represent a potential future strategy to avoid harmful radiation therapy as a primary tumor control together with surgery, Postprint (author's final draft)

The main objective of this paper is to study the effects of the processing parameters of the needle-punching machine and the interactions between them on some physico-mechanical properties of interest of nonwoven (NW) fabrics. For this purpose, a fractional factorial design has been planned with two levels for each factor: feeding speed, delivery speed, stroke frequency, penetration depth and gap between plates. Sixteen NW fabrics were obtained from polyester fibre and characterized by tensile strength and stiffness for mechanical behaviour and air permeability as physical properties of interest in some technical applications. The results have been subjected to statistical analysis in order to find the effects of the processing variables and the interactions between them on the fabric properties. It was possible to find the effects of the five processing parameters studied on the thickness, fabric mass, stiffness, tensile strength and air permeability of the obtained needle-punched fabrics, Postprint (published version)

The development of suitable biomimetic scaffolds is a fundamental requirement of tissue engineering. Although electrospinning has emerged as an effective method for producing such scaffolds of nanometer-sized fibers, the influence of solution characteristics on the morphology of the resulting nanofibers depends on each polymer solution system. In this study, gelatin nanofibers and microfibers were prepared via electrospinning using mixtures of water and acetic acid at different ratios as solvents. The viscosities of gelatin solutions before electrospinning were analyzed and two different behaviors were found as a function of the solvent composition, taking into account classic models of polymer science. A power law relationship between viscosity and gelatin concentration was found for each solvent system, and an empirical model including the influence of acetic acid was obtained for aqueous systems. Moreover, a ternary diagram considering gelatin, water, and acetic acid mass fractions was constructed as a tool to establish the electrospinnability domains in terms of fiber occurrence and morphology. Also, the isodiametric curves were defined in the fibers region. Finally, in order to correlate the diameter of electrospun nanofibers and the electrospinnability zones, the Berry number was used. However, as its only allows the range of electrospinnability to be established for a fixed solvent composition, a new dimensionless parameter (Bemod) was suggested to take into account all the acetic acid aqueous solutions as a single solvent, Postprint (published version)

The primary advantages of electrospun membranes include the ability to obtain very thin fibers that are on the order of magnitude of several nanometers with a considerable superficial area and the possibility for these membranes to be manipulated and processed for many different applications. The purpose of this study is to evaluate and quantify the transport mechanisms that control the release of drugs from polymer-based sandwich membranes produced using the electrospinning processes. These electrospun membranes were composed of poly(lactic acid) (PLA) because it is one of the most promising biodegradable polymers due to its mechanical properties, thermoplastic processability and biological properties, such as its biocompatibility and biodegradability. The transport mechanism that controls the drug delivery was evaluated via the release kinetics of a bioactive agent in physiological serum, which was used as a corporal fluid simulation. To describe the delivery process, mathematical models, such as the Power Law, the classical Higuchi equation and an approach to Fick's Second Law were used. Using the applied mathematical models, it is possible to conclude that control over the release of the drug is significantly dependent on the thickness of the membrane rather than the concentration of the drug., Peer Reviewed, Postprint (published version)

Postprint (published version)

Postprint (published version)

En la cirugía digestiva, una anastomosis del intestino consiste en la reconstrucción del tubo digestivo por unión de dos cabos tras la resección de una porción del mismo. Este procedimiento, de común aplicación en diversos tipos de intervención quirúrgica se realiza actualmente mediante la aplicación de grapas metálicas debido a la complejidad inherente de la realización de una sutura manual. La automatización del proceso de sutura mediante un dispositivo diseñado a tal efecto supondría una notable mejora en el procedimiento quirúrgico asociado y posteriormente en la calidad de vida del paciente, ya que las grapas metálicas empleadas actualmente presentan diversos inconvenientes. El diseño de este dispositivo presenta gran complejidad debido al rigor de los requisitos funcionales y a la complejidad del entorno de funcionamiento así como las características de los materiales que intervienen en el proceso.En el presente trabajo se describe el desarrollo de un prototipo de dispositivo para anastomosis automática mediante sutura, evaluando su funcionalidad a nivel de laboratorio, con objeto de probar su validez, Postprint (published version)

Postprint (published version)