Artículos (Ingeniería Química)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/53665

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Combining extrusion and hot compression molding for the development of bioplastics and nano-biocomposites based on rice bran
(Elsevier, 2025-08) Alonso González, María; Félix Ángel, Manuel; Romero García, Alberto; Pollet, Eric; Universidad de Sevilla. Departamento de Ingeniería Química; Ministerio de Ciencia e Innovación (MICIN). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Universidad de Sevilla. TEP229: Tecnología y Diseño de Productos Multicomponentes
The increasing interest in environmentally friendly plastic materials has driven the search for alternative raw materials to replace conventional oil-based plastics. Proteins and starches derived from renewable biomass have emerged as potential sources for the production of bioplastics due to their biodegradability and abundance. This research paper focuses on the development of bioplastics and nano-biocomposites based on rice bran through the combination of extrusion and compression molding. The study explores the optimization of processing conditions for the biopolymer matrix and investigates the influence of montmorillonite (MMT) nanoparticles as a reinforcement phase. The results demonstrate the successful development of rice bran-based bioplastics, where optimized extrusion and compression molding conditions enhanced mechanical performance (35% increase in storage modulus, 15% in tensile strength, and 30% in elongation at break). The addition of MMT nanoclay further enhances these properties, increasing rigidity and adjusting water uptake capacity. The study highlights the suitability of extrusion and hot compression molding for processing complex starch/protein mixtures, offering a viable approach for and the valorization of industrial by-products.
Rheological Properties and Physical Stability of Aqueous Dispersions of Flaxseed Fibers
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Alfaro Rodríguez, M. C.; García, M. C.; Prieto Vargas, P.; Muñoz García, José; Universidad de Sevilla. Departamento de Ingeniería Química; Junta de Andalucía
The main objective of this work is to investigate the influence of shear on the rheological properties and physical stability of aqueous dispersions of flaxseed fiber. The variable to consider will be the homogenization rate in two different rotor-stator homogenizers, Ultraturrax T50 or T25. In order to achieve the proposed objective, small amplitude oscillatory tests, flow curves, and multiple light scattering measurements were carried out. All samples exhibited a shear thinning behavior that was not influenced by the shear imposed, and a weak gel-like behavior. The latter, unlike the flow behavior, was sensitive to the homogenization rate. Thus, an increase in this variable caused a decrease in the viscoelastic moduli values. This result pointed out a weakening of the network formed by the flaxseed fiber in an aqueous medium. On the contrary, the physical stability improved. Nevertheless, all samples were highly stable. The homogenizer used was a significant variable. The shear negatively influenced the microstructure of the aqueous flaxseed fiber dispersions, although the obtained gels were highly stable. The gel-like behavior, the high viscosity at low shear rates, and the high physical stability of the samples studied make them interesting food stabilizers and thickeners.
Enabling low molecular weight electrospinning through binary solutions of polymer blends
(Elsevier, 2025-01) Pérez-Puyana, Víctor Manuel; Romero García, Alberto; Guerrero Conejo, Antonio Francisco; Moroni, Lorenzo; Wieringa, Paul; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. Departamento de Ingeniería Química; Ministerio de Economía y Competitividad (MINECO). España; Universidad de Sevilla. TEP229: Tecnología y Diseño de Productos Multicomponentes
The formation of nanofibrous membranes via electrospinning is typically restricted to high molecular weight polymers in an appropriate solvent, correlated with the necessary formation of polymer chain entanglements that are needed to achieve successful production of electrospun fibers. The present work extends the electrospinning of low molecular weight polymers by investigating the electrospinning of a binary solution system consisting of two different low molecular weight polymers, using as a model system polycaprolactone (PCL) and gelatin in different ratios. The viscosities of the polymer solutions were characterized as a proxy for polymer chain entanglement and the resulting fibers were morphologically characterized by SEM imaging and further assessed water contact angle and molecular composition to determine the impact and homogeneity of the binary mixtures. We found that unitary solutions of either PCL or gelatin failed to generate proper fibers despite indications of chain entanglement. In contrast, binary solutions of low molecular weight PCL and gelatin generated different fiber quality and size distributions, depending on the ratio used, with direct correlations between fiber properties and the PCL:Gelatin ratio. It was discovered that the ratio of PCL to gelation was most predictive for successful fiber generation, with effective electrospinning occurring only for a define intermediate range of high blend ratios while both low and high blended binary solutions resulted in poor fiber production. Our study confirmed that this behavior was independent from absolute polymer concentration, indicating a unique interaction between these binary species which exists only under specific ratio concentrations and indicates promising new avenues to process low molecular weight polymers solutions.
Application of non-invasive technologies in dry-cured ham: An overview
(Elsevier, 2019-04) Pérez-Santaescolástica, Cristina; Fraeye, Ilse; Barba, Francisco J.; Gómez, Belén; Tomasevic, Igor; Romero García, Alberto; Moreno, Andrés; Toldrá, Fidel; Lorenzo, José M.; Universidad de Sevilla. Departamento de Ingeniería Química; Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA)
Background: Dry-cured ham is one of the most valued food products by Mediterranean consumers. In this sense, the appropriate development of its different production stages is essential to ensure the quality requirements. For this reason, non-invasive technologies have gained popularity and have been reported as useful not only to ensure the food safety of different products, but also to monitor fundamental stages in the production process, such as the salting stage, to analyze the content of different compounds without sample losses, and to correct possible defects in the final product. Scope and approach: This work has been focused on summarizing the studies that describe and have successfully applied these techniques, as well as on mentioning other technologies with potential use in dry-cured ham manufacture which have not been studied enough. Finally, the potential next steps to improve and optimize the process, as well as the suitability of creating new products with added value based on the new quality standards, have also been evaluated. Key findings and conclusions: Innovative non-invasive technologies such as high pressure (HP), ultrasound (US), pulsed electric fields (PEF), microwaves, irradiation, etc. can be used as promising tools to effectively control salting and curing stages as well as for checking defects of the final product and/or ensuring food safety. HP and US are useful tools for the determination of salt and fat content, and for monitoring the salting process. Moreover, HP enhances salty taste perception, which makes it a useful tool to reduce salt addition. Both, HP and US, can correct texture defects. In addition, NIRS allows predicting the state of the meat to remove those pieces that could result in defective products. Moreover, RAMAN or MRI are able to detect anomalous textures at the end of the process. Microwaves could be useful for the online estimation of salt, water and fat contents easily with portable equipment. Finally, data mining, that allows to make predictions based on an immense data file, is the most promising discovery in recent years for detecting defects or classifying products according to sensory attributes.
Novel Food and Beverages: Production and Characterization
(Multidisciplinary Digital Publishing Institute (MDPI), 2024-07-01) Pérez-Puyana, Víctor Manuel; Jiménez Rosado, Mercedes; Romero García, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Ministerio de Ciencia e Innovación (MICIN). España
Development of a Multifunctional Chitosan-Based Composite Film from Crab Shell (Portunus segnis) and Algae (Ulva lactuca) with Enhanced Antioxidant and Antimicrobial Properties for Active Food Packaging
(Multidisciplinary Digital Publishing Institute (MDPI), 2024-12-27) Zaghbib, Imen; Abdullah, Johar Amin Ahmed; Romero García, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química; Ministerio de Ciencia e Innovación (MICIN). España
Eco-friendly, bioactive and edible films from renewable resources are increasingly regarded as viable replacements for petroleum-based packaging. This study investigates the application of Ulva lactuca macroalgae powder (ULP) as an active additive in crab (Portunus segnis) chitosan-based films for natural food packaging. Films with ULP concentrations of 0.5, 1.5, and 2.5% were prepared using a solvent-casting method with glycerol as a plasticizer. Their physicochemical, mechanical, functional, and biological properties were evaluated comprehensively. Fourier-transform infrared spectroscopy revealed intermolecular interactions between ULP’s polyphenolic compounds and the chitosan matrix, enhancing the films’ structural integrities. ULP’s incorporation reduced the moisture content, water solubility, lightness (L*), redness (a*), and whiteness index values while significantly (p < 0.05) increasing the yellowness (b*), total color difference (ΔE), yellowness index (YI), tensile strength (TS), and elongation at break (EB). The antioxidant activity improved in a concentration-dependent manner, as evidenced by the high free-radical scavenging capacity. Moreover, antimicrobial tests showed significant inhibitory effects against pathogenic strains. Biodegradability tests confirmed that the films decomposed entirely within 12 days under soil burial conditions, reinforcing their environmental compatibility. These results highlight the multifunctional potential of chitosan–ULP composite films, combining enhanced mechanical properties, bioactivity, and sustainability. By utilizing renewable and biodegradable materials, this work contributes to reducing waste and promoting resource efficiency, aligning with the principles of a circular economy and environmental preservation.
Effects of different pressing methods on physicochemical properties and volatile compounds of the apricot kernel oil
(Springer Nature, 2024-09-08) Zhang, Chen-Xiang; Guo, Peng-Hui; Zhang, Qing-An; García-Martín, Juan Francisco; Universidad de Sevilla. Departamento de Ingeniería Química; National Natural Science Foundation. China; Key Research Development Program of Shaanxi Province. China; Major Special Project of Erdos Science and Technology. China; Fundamental Research Funds for the Central Universities. China
In order to effectively utilize the nutrients in apricot (Prunus armeniaca L.) kernel, the apricot kernel oil was extracted by two pressing methods, i.e. cold pressing method and hot pressing method. The apricot kernel oils obtained were firstly debitterized and refined, and then their physicochemical properties and oxidation activities were determined by Lovibond tintometer, Rancimat method, differential scanning calorimeter, gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility mass spectrometry (GC-IMS). The results indicated that the baking pre-treatment on the apricot kernel in the hot pressing method increased the oil yield, changed the fatty acid profile, enriched the flavor characteristics, and prolonged the antioxidant properties of the oil. However, the apricot kernel oil in cold pressing method has a relatively lighter color and higher content of amygdalin. In conclusion, both cold and hot pressing methods are suitable pressing methods to obtain the apricot kernel oil that can meet people’s edible standards. Graphical Abstract: (Figure presented.)
Camphene/polystyrene solutions: A rheological approach for material processing industry
(John Wiley & Sons Inc., 2019-05-11) Félix Ángel, Manuel; Pérez-Puyana, Víctor Manuel; Paúl Escolano, Antonio; Sepúlveda Ferrer, Ranier Enrique; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Ministerio de Economia, Industria y Competitividad (MINECO). España
Rheological properties of polymer–camphene solutions are very relevant as they affect their stability, and they have many implications in operation costs. This work elucidates the rheological properties of polystyrene (PS–camphene) solutions with industrial applications. Unfortunately, the assessment of the very low shear viscosities of camphene-based materials (below 0.005 Pa s) is still a challenge with commercial rheometers. Flow curves, stress growth tests, and small amplitude oscillatory shear (SAOS) measurements were carried out as a function of PS concentration (0, 2.5, 5.0, 10, and 20 wt % PS) to understand the rheological behavior of these systems. Results indicate that liquid camphene has a shear-thinning behavior (flow index = 0.99) when the increase of polymer concentration involves changes in the structure of these systems (flow index = 0.10 for 20 wt % PS). An increase in PS concentration leads to a forwarding in the shear-thinning zone, and the Newtonian region (from ∼1 s−1, for 0 wt % PS, to 10−3 s−1 for 20 wt % PS). Eventually, these results evidence the high dependence of η∞ on PS concentration (from ∼1.16 ± 0.01 Pa s, for 0 wt % PS, to 631.5 ± 0.2 Pa s for 20 wt % PS). © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47953.
Prediction of quality traits in packaged mango by NIR spectroscopy
(Elsevier, 2025-02-16) Ding, Fangchen; García-Martín, Juan Francisco; Zhang, Li; Xu, Zhi; Lv, Daizhu; Chen, Xiao; Tu, Kang; Lan, Weijie; Pan, Leiqing; Universidad de Sevilla. Departamento de Ingeniería Química; Natural Science Foundation of Hainan Province; National Natural Science Foundation of China
Packaging with paper bags is essential for protecting mangoes during growth, but strongly berries near infrared (NIR) spectral signals used for non-invasive analysis of their internal quality. This study focused on eliminating or minimizing the interference of paper bags on the NIR spectra of mangoes and developed innovative solutions to accurately assess mango firmness (FI), dry matter content (DMC), soluble solids content (SSC), and titratable acidity (TA). Specific NIR signals at around 1150–1250 nm and 2100–2400 nm were highlighted, which significantly reduced the precision of NIR predictions for these quality traits. A deep learning-based fully connected neural network (FNN) combined with Gaussian spatial (GS) filtering were applied as an effective strategy to mitigate the spectral interferences of packaged mangoes. Additionally, partial least squares regression (PLSR) consistently outperformed principal components regression (PCR) across all quality traits based on the spectra of packaged mangoes after FNN correction and GS filtering (PMs-FNN-GS), with Rp2 and RMSEP values of 0.847 and 10.705 N, 0.932 and 0.320 % for DMC, 0.821 and 1.211 % for SSC, and 0.907 and 0.032 % for TA, demonstrating that reliable predictive accuracy for packaged mangoes was effectively achieved through the combination of deep learning and GS filtering.
Synthesis of Marine (-)-Pelorol and Future Perspectives
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Rosales Martínez, Antonio; Rodríguez García, Ignacio; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla; Universidad de Almería; European Union (UE). H2020
Meroterpenoid-type marine natural compounds have attracted an increasing amount of attention due to their peculiar chemical structures and their potential for the development of therapeutically important probes. Within this group of substances pelorol stands out; it is a natural compound isolated from marine organisms with a unique structure and an interesting biological profile. In this article, we summarize and highlight the most interesting aspects of the synthetic procedures towards this compound, which have two common key steps. The first is the coupling of a drimanyl derivative with a compound derived from an arene. The second is a Friedel–Crafts cyclization which forms the C ring of the natural product. Despite the synthetic advances achieved so far, we consider that a more efficient synthetic procedures could be carried out, since their synthetic routes are difficult to scale up due to numerous reaction steps and the limitations imposed by the use of some reagents. In this article, we present a new and versatile retrosynthetic analysis of (-)-pelorol and analogs, which is highly desirable for their easy preparation and subsequent broad study of their biological activities. This is a retrosynthetic route that could improve those reported in the literature in terms of cost-effectiveness.
Innovations and New Processes in the Olive Oil Industry
(2024-07-26) Sánchez Villasclaras, Sebastián; García-Martín, Juan Francisco; Universidad de Sevilla. Departamento de Ingeniería Química
Advances in Vibrational Spectroscopic Techniques for the Detection of Bio-Active Compounds in Virgin Olive Oils: A Comprehensive Review
(MDPI, 2024-12-03) Ding, Fangchen; Sánchez Villasclaras, Sebastián; Pan, Leiqing; Lan, Weijie; García-Martín, Juan Francisco; Universidad de Sevilla. Departamento de Ingeniería Química
Vibrational spectroscopic techniques have gained significant attention in recent years for their potential in the rapid and efficient analysis of virgin olive oils, offering a distinct advantage over traditional methods. These techniques are particularly valuable for detecting and quantifying bio-active compounds that contribute to the nutritional and health benefits of virgin olive oils. This comprehensive review explores the latest advancements in vibrational spectroscopic techniques applied to virgin olive oils, focusing on the detection and measurement of key bio-active compounds such as unsaturated fatty acids, phenolic compounds, and other antioxidant compounds. The review highlights the improvements in vibrational spectroscopy, data processing, and chemometric techniques that have significantly enhanced the ability to accurately identify these compounds compared to conventional analytical methods. Additionally, it addresses current challenges, including the need for standardized methodologies and the potential for integrating vibrational spectroscopy with other analytical techniques to improve accuracy and reliability. Finally, findings over the last two decades, in which vibrational spectroscopy techniques were effectively used for the detailed characterization of bio-active compounds in virgin olive oils, are discussed.
Sustainable Synthesis of ZnO and FexOy Nanoparticles and their Nanocomposite ZnFe2O4: Comprehensive Characterization and Applications in Antioxidant Activity and Antibiotics Degradation Efficiency
(Elsevier, 2024) Abdullah, Johar Amin Ahmed; Ali Mohammed, Hamdi; Salmi, Chaima; Alqarni, Zarah; Eddine Laouini, Salah; Guerrero Conejo, Antonio Francisco; Romero García, Alberto; Universidad de Sevilla. Departamento de Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España
This study focuses on developing and evaluating eco-friendly nanoparticles, specifically FexOy NPs, ZnO NPs, and a ZnFe2O4 nanocomposite (NC), for potential applications in environmental remediation and biomedicine. The nanoparticles were synthesized and characterized using X-ray diffraction (XRD), which revealed their crystalline structures with sizes of 20.3 nm for FexOy NPs, 22.1 nm for ZnO NPs, and 10.9 nm for ZnFe2O4 NC. Fourier-transform infrared (FTIR) spectroscopy identified functional groups, while UV–visible spectroscopy determined band gap energies of 2.35 eV, 3.38 eV, and 2.68 eV for FexOy NPs, ZnO NPs, and ZnFe2O4 NC, respectively. Morphological analysis via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that FexOy NPs have cubic, hexagonal, and tetragonal forms, ZnO NPs are hexagonal nanorods, and ZnFe2O4 NC has a hexagonal-faced cubic structure. Antioxidant activity, assessed through the DPPH assay, revealed that ZnFe2O4 NC had the highest potency. Additionally, under sunlight irradiation, ZnFe2O4 NC demonstrated superior degradation of the antibiotic cephalexin (96 % within 30 min) compared to FexOy NPs (58.2 %) and ZnO NPs (52 %), with respective kinetic rate constants of 0.109 min−1, 0.029 min−1, and 0.025 min−1. These results highlight the nanoparticles’ potential for environmental and biomedical applications.
Plasma-flash Sintering: Metastable Phase Stabilization and Evidence of Ionized Species
(John Wiley & Sons, 2025) Gil González, Eva; Taibi, A.; Perejón Pazo, Antonio; Sánchez Jiménez, Pedro Enrique; Pérez Maqueda, L. A.; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla. Departamento de Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España; Universidad de Sevilla
The first demonstration of plasma-flash sintering (PFS) is presented in this work. PFS is performed under a low-pressure atmosphere that consecutively generates plasma and flash events. It is shown, by using several combined characterization techniques, that PFS stabilizes metastable phases on the surface of the material, which may be partially, but not solely, attributed to the generation of oxygen vacancies, and induces the absorption of ionized species, if a reactive atmosphere is employed. Even though additional research is required to understand the fundamentals of PFS, it is evidenced its potential to be used as a material surface engineering tool, which may widen the technological capabilities of flash sintering.
Optimization of Processing Conditions for Rice Bran-based Bioplastics Through Extrusion and Injection Molding
(Springer Nature, 2024) Alonso González, María; Félix Ángel, Manuel; Romero García, Alberto; Sergi, C.; Bavasso, I.; Sarasini, F.; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla
Conventional plastics pose environmental threats due to their non-biodegradable nature and their reliability on fossil resources, leading to the exploration of sustainable alternatives. In this sense, biodegradable bioplastics derived from renewable resources offer a promising solution to mitigate ecological impacts. This study focuses on the combination of extrusion and injection molding for the development of rice bran-based bioplastics. Being a by-product from the rice industry rich in starches and proteins, rice bran is an abundant and non-expensive resource that contributes to an enhanced waste management and represents a step forward in integrating the principles of a circular economy. This study delves into the optimization of processing conditions through a Design of Experiment approach. For this purpose, the number of extrusion steps, cylinder and mold temperatures, and injection pressure were investigated. The results showed that two extrusion steps led to a significant increase of approximately 22.8% in Young’s modulus and 37.5% in tensile strength compared to a single extrusion cycle. This enhancement was attributed to the facilitation of starch gelatinization and biopolymer-plasticizer interactions (achieving thermoplastic starch and protein plasticization). Similarly, manipulation of injection temperatures and pressure had notable effects on tensile properties, highlighting the complex interplay between processing parameters. In particular, when using cylinder and mold temperatures of 110 °C and 180 °C, respectively, along with 800 bar, it was possible to achieve a further enhancement in tensile properties, with an increase of 97.1% in Young’s modulus and over 100% in tensile strength. Overall, this research underscores the importance of understanding the relationship between processing conditions and biopolymer interactions for bioplastic production.
Mechanical Stimulation and Aligned Poly(ϵ-caprolactone)-Gelatin Electrospun Scaffolds Promote Skeletal Muscle Regeneration
(American Chemical Society, 2024) Calero Castro, Francisco José; Pérez-Puyana, Víctor Manuel; Laga, I.; Padillo Ruiz, Francisco Javier; Romero García, Alberto; Portilla de Juan, Fernando de la; Universidad de Sevilla. Departamento de Ingeniería Química; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía; Instituto de Salud Carlos III
The current treatments to restore skeletal muscle defects present several injuries. The creation of scaffolds and implant that allow the regeneration of this tissue is a solution that is reaching the researchers’ interest. To achieve this, electrospinning is a useful technique to manufacture scaffolds with nanofibers with different orientation. In this work, polycaprolactone and gelatin solutions were tested to fabricate electrospun scaffolds with two degrees of alignment between their fibers: random and aligned. These scaffolds can be seeded with myoblast C2C12 and then stimulated with a mechanical bioreactor that mimics the physiological conditions of the tissue. Cell viability as well as cytoskeletal morphology and functionality was measured. Myotubes in aligned scaffolds (9.84 ± 1.15 μm) were thinner than in random scaffolds (11.55 ± 3.39 μm; P = 0.001). Mechanical stimulation increased the width of myotubes (12.92 ± 3.29 μm; P < 0.001), nuclear fusion (95.73 ± 1.05%; P = 0.004), and actin density (80.13 ± 13.52%; P = 0.017) in aligned scaffolds regarding the control. Moreover, both scaffolds showed high myotube contractility, which was increased in mechanically stimulated aligned scaffolds. These scaffolds were also electrostimulated at different frequencies and they showed promising results. In general, mechanically stimulated aligned scaffolds allow the regeneration of skeletal muscle, increasing viability, fiber thickness, alignment, nuclear fusion, nuclear differentiation, and functionality.
A Novel Approach for Microbial Activity Assessment in Bioleaching. Towards to a Standardised Fast Starting up Protocol
(Elsevier, 2024) Perdigones, Blanca; Ramírez del Amo, Pablo; Mazuelos Rojas, Alfonso; Universidad de Sevilla. Departamento de Ingeniería Química; European Union (UE). H2020
Biohydrometallurgy is a proven industrial method for extracting base metals from sulfidic ores with low-grade content and as a pre-treatment of Au ores. The lack of study of biological aspects related with microbial activity assessment makes it difficult to control and monitor these processes; and the multitude of experimental procedures described in the literature hinders cross-study comparisons among researchers. Experimental tools that allow a quick and reliable quantitative assessment of the iron oxidising capacity of the cells during the bioleaching process are needed. This work proposes monitoring microbial activity through a simple and reliable method based on the offline measurement of the Oxygen Uptake Rate (OUR). The methodology allows to quantify the microbial activity evolution of a growing culture under no-limiting conditions. By this methodology, the maximum potential bioleaching rate of the culture at any time is determined, assessing the occurrence of a biological or chemical limitation. The results obtained reveals that whether due to Fe2+ or O2 depletion, substrate availability significantly limits microbial activity. This aspect is key to assess a culture suitability for bioleaching bioreactor inoculation, preventing long lag phases. Furthermore, the methodology allows for quick disturbances correction, avoiding process shutdowns and enhances technological reliability of continuous bioleaching.
Aerogels Based on Chitosan and Collagen Modified with Fe₂O₃ and Fe₃O₄ Nanoparticles: Fabrication and Characterization
(Multidisciplinary Digital Publishing Institute (MDPI), 2025-01-08) Granados Carrera, Carmen M.; Castro Criado, Daniel; Abdullah, Johar Amin Ahmed ; Jiménez Rosado, Mercedes; Pérez-Puyana, Víctor Manuel; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Ministerio de Ciencia e Innovación (MICIN). España
The necessity to mitigate the intrinsic issues associated with tissue or organ transplants, in order to address the rising prevalence of diseases attributable to increased life expectancy, provides a rationale for the pursuit of innovation in the field of biomaterials. Specifically, biopolymeric aerogels represent a significant advancement in the field of tissue engineering, offering a promising solution for the formation of temporary porous matrices that can replace damaged tissues. However, the functional characteristics of these materials are inadequate, necessitating the implementation of matrix reinforcement methods to enhance their performance. In this study, chemical and green iron oxide nanoparticles, previously synthesized and documented in existing research, were incorporated into hybrid aerogels combining collagen (C) and chitosan (CH). The characterization of these aerogels was conducted through rheological, microstructural, and functional analyses. The results demonstrate that the incorporation of iron oxide nanoparticles has a significant influence on the properties of the aerogels fabricated with them. In particular, the incorporation of these nanoparticles has been observed to modify the mechanical properties, with an increase in strength and porosity that may support cell proliferation.
Enhanced porous titanium biofunctionalization based on novel silver nanoparticles and nanohydroxyapatite chitosan coatings
(Elsevier, 2025-04) Castillejo, Ana; Martínez Muñoz, Guillermo; Delgado-Pujol, Ernesto J.; Villalobo Polo, Eduardo; Carrillo de la Fuente, Francisco; Casado Jurado, David; Pérez Bernal, Juan Luis; Begines Ruiz, Belén; Torres Hernández, Yadir; Alcudia Cruz, Ana; Universidad de Sevilla. Departamento de Química Orgánica y Farmacéutica; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte; Universidad de Sevilla. Departamento de Química Analítica; Universidad de Sevilla. Departamento de Ingeniería Química; Universidad de Sevilla. Departamento de Microbiología; Ministerio de Ciencia e Innovación (MICIN). España
Titanium is widely used for implants however it presents limitations such as infection risk, stress shielding phenomenon, and poor osseointegration. To address these issues, a novel approach was proposed that involves fabricating porous titanium substrates, to reduce implant stiffness, minimizing stress shielding and bone resorption, and applying polymeric coatings to improve bioactivity. Composite coating prepared from chitosan, silver nanoparticles, and nanohydroxyapatite was optimized to enhance antibacterial properties and promote osseointegration. Chitosan with 80.5 % of deacetylation degree was used to prepare composites with diverse compositions, including different methodologies of adding silver nanoparticles, with silver concentrations below toxic level. Antibacterial activity was tested with three different strains, including Gram+ and Gram− bacteria, demonstrating excellent inhibition after 21 days. In addition, the induction of hydroxyapatite formation was investigated. Finally, the optimal porous metallic substrate that exhibited a more suitable stiffness (29 GPa) (close to the cortical bone tissue they intend to replace) was chosen to be infiltrated with the selected composites. In summary, this synergistic approach based on the combination of porous titanium substrates with 60 vol% porosity and a 355–500 μm pore size distribution coated with 3%CS-nHA-AgNPs-TPP-AgNPsbath composite provided a potential solution to provide implants with improved biomechanical balance and biofunctionality.
Eco-friendly protein-based materials for a sustainable fertilization in horticulture
(Elsevier, 2021-03-01) Jiménez-Rosado, Mercedes; Rubio Valle, José Fernando; Pérez-Puyana, Víctor Manuel; Guerrero Conejo, Antonio Francisco; Romero García, Alberto; Universidad de Sevilla. Departamento de Ingeniería Química; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; Universidad de Sevilla. TEP229: Tecnología y Diseño de Productos Multicomponentes
Actually, there is a need to develop more sustainable novel techniques for incorporating fertilizers into crops. Researchers have proposed the controlled release of these fertilizers from biodegradable protein-based matrices. This technique must be optimized, as it involves a higher initial incorporation of micronutrients compared to that eventually retained by the matrix. The aim of this research was to improve the plasticizer removal stage in order to minimize the loss of micronutrient. To this end, three different aqueous media were used for the elimination of the plasticizer: water, ethanol and a mixture of both. The capacity of the media to remove the plasticizer and the retention of micronutrient by the matrices were evaluated. Furthermore, the mechanical, microstructural and functional properties of the matrices were analyzed. This work has showed that it is possible to optimize the process, obtaining matrices with higher micronutrient retention.

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