Leyre Perez

• Associate Professor
• University of the Basque Country

Determining the values of various properties for new bio-inks for 3D printing is a very important task in the design of new materials. For this purpose, a large number of experimental works have been consulted, and a database with more than 1200 bioprinting tests has been created. These tests cover different combinations of conditions in terms of p...

Determining the values of various properties for new bioinks for 3D printing is a very important task in the design of new materials. For this purpose, a large number of experimental works have been consulted and a database with >1200 bioprinting tests has been created. These tests cover different combinations of conditions in terms of print pressu...

The increasing production of plastics, driven by modern societal development, has resulted in a significant rise in plastic waste, which poses serious environmental concerns due to its lengthy degradation times. The growing issue of single-use plastics (SUPs), such as packaging for food items and disposable utensils, has led to their reduction and...

The study delves into the use of the thiol-yne click reaction to enhance (bio)conjugation methodologies, particularly focusing on immobilizing biomolecules onto PLLA surfaces. The thiol-yne click reaction, known for its efficiency, selectivity, and versatility in forming carbon-sulfur bonds under mild conditions without transition metal catalysts,...

Naturally derived biopolymers modifying or combining with other components are excellent candidates to promote the full potential of additive manufacturing in biomedicine, cosmetics, and the food industry. This work aims to develop new photo-cross-linkable alginate-based inks for extrusion 3D printing. Specifically, this work is focused on the effe...

Photocuring of chitosan has shown great promise in the extrusion-based 3D printing of scaffolds for advanced biomedical and tissue engineering applications. However, the poor mechanical stability of methacrylated chitosan photocuring ink restricts its applicability. The inclusion of co-networks by means of simultaneous polycomplex formation is an e...

Anthocyanins are a specific group of molecules found in nature that have recently received increasing attention due to their interesting biological and colorimetric properties that have been successfully applied in several fields such as food preservation and biomedicine. Consequently, reviews devoted to a general overview of these flavonoids have...

Self-standing nanocomposite films were prepared by three-dimensional UV-induced radical copolymerization of methacrylated alginate (MALG) with acrylic acid (AA) and reinforced with graphene oxide (GO) to improve both mechanical strength and dye adsorption capacity in wastewater decontamination operations. Dynamic mechanical–thermal analysis reveale...

This paper reviews different approaches to obtain biomaterials with tailored functionalities and explains their significant characteristics that influence their bioactivity. The main goal of this discussion underscores the significance of surface properties in materials, with a particular emphasis on their role in facilitating cell adhesion in orde...

3D inprimaketa edo fabrikazio gehigarria azkar ari da hedatzen produktuen diseinu eta fabrikazio modu desberdinak ahalbidetzen dituelako. Izan ere, teknologia honi esker propietate pertsonalizagarriak, diseinu-askatasuna eta geometria konplexuak sor daitezke. Hala ere, 3D inprimaketarako tinta gehienek disolbatzaile organikoak erabiltzen dituzte, e...

Among biomedical community, great efforts have been realized to develop antibacterial coatings that avoid implant-associated infections. To date, conventional mono-functional antibacterial strategies have not been effective enough for successful long-term implantations. Consequently, researchers have recently focused their attention on novel bifunc...

Due to the environmental problems generated by petroleum derivative polymers as mentioned in Agenda 2030, the use of natural polymers is increasing. Among them, cellulose and chitin are the most widespread biopolymers available in nature. Chitosan, obtained from chitin, is a really good candidate to develop nanocarriers due to its polyelectrolyte n...

Biobased resources are proposed as next‐generation materials for advanced application. Among them, silk fibroin, a protein‐based material generally obtained from Bombyx mori cocoons, is considered to play an increasing role in the development of a more sustainable generation of devices. In this review, the silk fibroin molecular structure and its o...

Today, the treatment of implant-associated infections with conventional mono-functional antibacterial coatings has not been effective enough for a prosperous long-term implantation. Therefore, biomedical industry is making considerable efforts on the development of novel antibacterial coatings with a combination of more than one antibacterial strat...

Today, Ti6Al4V alloy is the most used and manufactured metallic implantable biomaterial in biomedical industry. However, in recent years it has demonstrated that Ti6Al4V based biomaterials could induce harmful diseases to human health in long-term implantations. Thus, biomedical community makes great efforts in order to improve the biocompatibility...

In situ-forming, biodegradable, and self-healing hydrogels, which maintain their integrity after damage, owing to dynamic interactions, are essential biomaterials for bioapplications, such as tissue engineering and drug delivery. This work aims to develop in situ, biodegradable and self-healable hydrogels based on dynamic covalent bonds between N-s...

Biocompatible and biodegradable hydrogels with biomimetic properties, such as self-repairing, are increasingly interesting for biomedical applications, particularly when they can be printed or in situ formed to mimic extracellular matrix or as personalized implantable devices in tissue regeneration or drug delivery. Photocrosslinkable hydrogels bas...

Soft materials are attracting much attention for the development of biostructures able to mimic the movement of natural systems by remote actuation. Multi-sensitive hydrogels are among the best materials for obtaining dynamic and biocompatible soft structures for soft actuators and related biomedical devices. Nevertheless, bioinks based on naturall...

Great efforts have been performed on the production of advanced biomaterials with the combination of self-healing and wound healing properties in implant/tissue engineering biomedical area. Inspired by this idea, chitosan (CHI) based hydrogels can be used to treat a less investigated class of harmful chronic wounds: ulcers or pressure ulcers. Thus,...

Hyaluronic acid (HA) injectable biomaterials are currently applied in numerous biomedical areas, beyond their use as dermal fillers. However, bacterial infections and painful inflammations are associated with healthcare complications that can appear after injection, restricting their applicability. Fortunately, HA injectable hydrogels can also serv...

Polymer scaffolds are playing an increasing role in tissue engineering (TE), although there is still a need to improve their biomimicry of cellular microenvironments, by having smart scaffolds with an active response, which can improve tissue regeneration. This work reports on the novel combination of poly(lactic-co-glycolide) (PLGA) with the ionic...

Spontaneously formed hydrogels are attracting increasing interest as injectable or wound dressing materials because they do not require additional reactions or toxic crosslinking reagents. Highly valuable properties such as low viscosity before external application, adequate filmogenic capacity, rapid gelation and tissue adhesion are required in or...

The combination of electroactive polymers and ionic liquids (ILs) has been gaining much attention for tissue engineering. Thus, this work reports on the development of oriented electrospun fibers and films based on poly(vinylidene fluoride) (PVDF) and polyhydroxybutyrate-co-hydroxyvalerate (PHBV) blended with the IL choline acetate ([Chol][Ac]). Th...

Three-dimensional (3D) printing represents a suitable technology for the development of biomimetic scaffolds for biomedical and tissue engineering applications. However, hydrogel-based inks’ printability remains a challenge due to their restricted print accuracy, mechanical properties, swelling or even cytotoxicity. Chitosan is a natural-derived po...

Chitosan (CHI) based hydrogels promote wound healing and relieve inflammations and chronic infections. However, in hardly healable ulcers with excessively painful inflammations, anti-inflammatory activity of hydrogels can be enhanced by the sustained release of non-steroidal anti-inflammatory drugs or combining them with antibiotics. Thus, CHI was...

Electrospun membranes play an increasing role in tissue regeneration base on their suitable morphological features. The implementation of active response, such as magnetically responsiveness or piezo-ionic features can further improve tissue regeneration by better resembling varying microenvironment during cell culture. In this context, this work r...

Titanium (Ti) and its alloys have been demonstrated over the last decades to play an important role as inert materials in the field of orthopedic and dental implants. Nevertheless, with the widespread use of Ti, implant-associated rejection issues have arisen. To overcome these problems, antibacterial properties, fast and adequate osseointegration...

Natural polymers are a promising alternative for reducing the environmental impact of batteries. For this reason, it is still necessary to study their behavior and implement its use in these devices, especially in separator membranes. This work reports on new separator membranes based on silk fibroin (SF) and silk sericin (SS) prepared by salt leac...

Multifunctional printable biomaterials are at the base of advanced biomedical applications. Chitosan (CHI) and hyaluronic acid (HA) allow the development of polycomplex hydrogels with tailorable properties, including self-healing and controlled drug release. This work correlates and optimizes the mucoadhesive, swelling, biodegradation, mechanical a...

In order to advance towards more sustainable electronics generation, natural polymers with tailored dielectric response are essential. In this search, the combination of bio-based materials with active fillers in composite form, suppose one of the most viable alternatives. To achieve it, this work has explored the ability to control dielectric resp...

N -Methyl-2-pyrrolidone is a toxic dipolar aprotic solvent widely used in the synthesis of polyurethane dispersions (PUD).

Bacterial contamination in implanted biomedical devices is a critical daily concern. The most used material for permanent implant in biomedical field is Ti6Al4V alloy due to its beneficial mechanical properties and high biocompatibility. Accordingly, in this work different polymeric antibacterial coatings poly(N-vinyl pyrrolidone) (PVP), hyaluronic...

In this research a chemical modification of kraft lignin was carried out using a basic nucleophilic substitution reaction (NSA) in order to functionalize it as a novel crosslinking agent for the synthesis of active hydrogels. The chemical modification success of the synthesized crosslinker was demonstrated by using several techniques such as volume...

Hyaluronic acid (HA) solutions were crosslinked with divinyl sulfone (DVS) and subsequently loaded with antibiotic molecules to obtain biocompatible and antibacterial injectable hydrogels. The crosslinking degree of the hydrogels was modulated by varying the reaction time and the HA:DVS weight ratio. Synthesized HA-DVS hydrogels were characterized...

Hydrogels present a great number of advantages, such as their swelling capacity or their capability to mimic tissues, which make them very interesting biomaterials. However, one of their main disadvantages is their lack of good mechanical properties, which could limit some of their applications. Several strategies have been carried out to develop h...

Stimulus-sensitive hydrogels have become suitable soft and multifunctional materials for biomedical applications such as, tissue engineering, soft robotic actuators or controlled release of bioactive substances, such as drugs, growth factors, or cells. In addition, these materials are promising candidates for the manufacture of customized scaffolds...

In situ hydrogels have attracted increasing interest in recent years due to the need to develop effective and practical implantable platforms. Traditional hydrogels require surgical interventions to be implanted and are far from providing personalized medicine applications. However, in situ hydrogels offer a wide variety of advantages, such as a no...

This work focuses on the development of a novel generation of bio-based advanced multifunctional materials, able to replace the synthetic ones and thus contributing to sustaibanility. Silk Fibroin (SF), a protein obtained from Bombyx mori cocoons, has been selected due to its natural accessibility, physico-chemical properties and facile processabil...

The last years have seen a general rise in individual awareness on the environmental issues that our society is about to face. The almost total scientific agreement over Global Warming and the day-by-day growing evidences of plastic pollution have fed requests worldwide to public institutions to take actively part in a radical change in today conce...

The present work reports on the control of silk fibroin (SF) porous structures performance through various processing methods. The study includes the analysis of two dissolving techniques (CaCl2/H2O/EtOH ternary and LiBr/H2O binary solutions), three regeneration methods (gelation, lyophilization and gas foaming) and one post-processing (EtOH). In a...

Thermosensitive hydrogels based on polysaccharides are suitable candidates for the design of biodegradable and biocompatible injectable drug delivery systems. Thus, the combination of chitosan (CHI) and β-glycerol phosphate disodium salt (β-GP) has been intensively investigated to develop thermo-induced physical gels. With the aim of exploring the...

Nanometric gel particles (CsSH/PEGBCOOH) were successfully synthesized through water in oil (W/O) emulsion by the covalent cross–linking between the primary amines of thiolated chitosan (CsSH) and the dicarboxylic poly(ethylene glycol) (PEG) derivative as cross–linker (PEGBCOOH). Thus, the amidation reaction led to the formation of stable nanosized...

There is an increasing interest in developing advanced materials based on natural resources. In this article, Senentxu Lanceros‐Méndez, Carlos M. Costa, and co‐workers, article number 2000111, report on magnetic nanocomposites based on Silk Fibroin (SF) polymer with magnetic CoFe2O4 (CFO) nanoparticles. Together with the discussion of the physico‐c...

Bone-related diseases are one of the most common health conditions that limit the quality of life of elderly. Novel materials for bone tissue engineering that actively assist on the regeneration of bone tissue are thus needed. In this work, magnetoactive scaffolds comprised of silk fibroin (SF) with different content of filler – cobalt ferrite nano...

The need for technologies based environmentally friendlier materials, able to minimize the global dependence on fossil fuel derivatives, promotes the development of new hybrid materials based on natural polymers, such as silk derivatives. This work reports on a new generation of magnetically active materials based on silk fibroin (SF) from Bombyx m...

Biodegradable, non-toxic and transparent poly (l-lactic acid) (PLLA) biopolymer is modified in order to obtain an improved material with antibacterial properties for its use as active packaging of food. For this, PLLA films were endowed with the bactericidal effect of ZnO nanoparticles by internal blending and the bacteria contact-killing propertie...

Biomedical devices have become essential in the health care. Every day, an enormous number of these devices are used or implanted in humans. In this context, the bacterial contamination that could be developed in implanted devices is critical since it is estimated that infections kill more people than other medical causes. Commonly, these infection...

Azken urteetan, inplante kirurgikoak oso erabiliak bilakatu dira kaltetutako hezurrak, lotailuak edota giharrak ordezkatzeko. Hala ere, hauen erabilera dela eta ezinbestekoa da antibiotikoen tratamendua jasotzea, inplanteetan aurki daitezkeen bakteria eta beste mikroorganismoei aurre egiteko. Orokorrean, bakterioak inplanteen gainazaletan adsorbatz...

Polymers obtained from biomass are an interesting alternative to petro-based polymers due to their low cost of production, biocompatibility, and biodegradability. This is the case of lignin, which is the second most abundant biopolymer in plants. As a consequence, the exploitation of lignin for the production of new materials with improved properti...

Biodegradable shape-memory polymers (BSMP) have arisen as highly promising materials for biomedical applications due to their valuable properties. Their chemical and structural diversities, low toxicity, biodegradation, and resorption added to their capability to adapt their shape due to their shape-memory property make them excellent materials for...

There is currently an increasing interest in the development of polyacrylonitrile (PAN)-based membranes with new and enhanced properties which are of special importance in the processes of pervaporation, purification, and water treatment. Thus, the optimization of the functionalization of PAN membranes and its effect on their morphology, hydrophili...

The search of natural materials for their application in energy storage systems in general and batteries in particular is growing due to their promising properties and the need of environmental sustainability. Silk fibroin (SF) is one of those materials due to their mechanical and thermal properties, non-toxicity and biocompatibility. Further, SF e...

Ehun ingeniaritzak kaltetuta dauden ehunen ordezko funtzionalak sintetizatzeko helburua dauka. Horretarako, zelulaz, molekula bioaktiboz eta euskarri porotsuz osatutako matrizeak beharrezkoak dira, hazkuntza eta zelulen diferentziazio prozesuak gerta daitezen. Matrize hauek solidifikatzeko gai den aitzindari baten injekzioz eratu daitezke kaltetuta...

This work reports on the development of ionic liquid (IL)/ silk fibroin (SF) composite films as electroactive polymers actuators. Different contents (20, 40 and 60% wt.) of 1-butyl-3-methylimidazolium tricyanomethanide ([Bmim][C(CN3)]) and choline dihydrogen phosphate ([Ch][DHP]) ILs were incorporated into the SF polymer matrix. Due to IL-SF intera...

In this work the immobilization of hybrid polyoxometalates (POMs) onto functional polymeric surfaces is exposed and discussed. Thus, various hybrid polymer‒inorganic films were prepared by anchoring selected hybrid POMs onto tailored polymeric surfaces that consisted of breath figures (BFs) made of polystyrene-b-poly(acrylic acid)/polystyrene (PS-b...

The development of strategies to mimic the natural environment of tissues with engineered scaffolds remains one of the biggest challenges of tissue engineering. Hydrogels appear as suitable materials for this purpose due to their substantial water content, biocompatibility, and for being able to carry nanomaterials that introduce new functionalitie...

Stable hyaluronic acid nanogels were obtained following the water-in-oil microemulsion method by covalent crosslinking with three biocompatible crosslinking agents: Divinyl sulfone, 1,4-butanediol diglycidyl ether (BDDE), and poly(ethylene glycol) bis(amine). All nanoparticles showed a pH-sensitive swelling behavior, according to the pKa value of h...

Environmental issues promote the development of sensors based on natural polymers that are becoming an area of increasing interest. Piezoresistive sensors based on silk fibroin with carbon nanotubes (CNT) as fillers were produced by solvent-casting in order to tune their electrical conductivity and electromechanical response. It is shown that the c...

This work investigates the effect of the incorporation of zinc oxide (ZnO) nanoparticles within a poly(l‐lactic acid) (PLLA) matrix as an approach to speed up the hydrolysis of PLLA film surfaces. Hydrolysis was done by immersing nanocomposite films having 1 wt % of ZnO in 0.25 M sodium hydroxide at 58 °C. This concentration has been selected as it...

Polyoxometalates (POMs) have been revealed as interesting antitumor agents inhibiting the action of Sox2 transcription factor, which reduces the risk of metastasis during hormonal therapies. However, they have shown serious concerns to be incorporated into the cells due to their cytotoxicity. Taking this into consideration, this study aims to devel...

Polymeric thin films patterned with honeycomb structures were prepared from poly(x-chlorostyrene) and statistical poly(x-chlorostyrene-co-styrene) copolymers by static breath figure method. Each polymeric sample was synthesized by free radical polymerization and its solution in tetrahydrofuran cast on glass wafers under 90% relative humidity (RH)....

Bacterial contamination is a critical problem in medical implants, which are preferential sites for bacterial adhesion, leading to infections which can compromise health and immune system of patients. Commercial titanium alloys are the most commonly used materials for permanent implants in contact with bone, and the prevention of infections on thei...

Antibacterial coatings have been widely explored to inhibit biofilm formation in order to prevent post-implantation infections of biomedical devices. However, due to the complex mechanism of bacterial adhesion and proliferation, only the combination of different strategies can lead to higher antibacterial efficiency, especially in the initial stage...

There is a wide demand for new biodegradable materials with innovations to improve the basic functions of traditional food packaging and prolong the shelf life of food, enhancing its security and sensorial properties. Poly(L-lactic acid) (PLLA) is a biodegradable biopolymer used in traditional packaging of food because of its non-toxicity, biodegra...

Naturan auto-garbiketa edo bakterioen aurkako propietate bitxiak aurkezten dituzten izaki bizidun ugari daude. Lan honetan, ñame edo loto lorea bezalako landareak eta zenbait animaliak aurkezten dituzten propietateak, hauen gainazaleko topografiarekin eta bustitze-ahalmenarekin erlazionatuko dira. Gainazalaren azterketa sakonek agerian utzi dute ga...

Polymer-based piezoelectric biomaterials have already proven their relevance for tissue engineering applications. Furthermore, the morphology of the scaffolds plays also an important role in cell proliferation and differentiation. The present work reports on poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV), a biocompatible, biodegradable, and piezoe...

Polymer-based piezoelectric biomaterials have already proven their relevance for tissue engineering applications. Further, the morphology of the scaffolds plays also an important role in cell proliferation and differentiation. The present work reports on poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV), a biocompatible, biodegradable and piezoelectr...

Traditional absorbent hydrogels are based on the copolymerization of petroleum-based synthetic vinyl monomers such as acrylic acid, methacrylic acid, and acrylamide derivatives. Nevertheless, these materials are usually expensive, poorly degradable, and non-environmentally friendly. On the contrary, natural polysaccharides display significant advan...

To enhance critical thinking and problem-solving skills, a project-based learning (PBL) approach for “Instrumental Techniques” courses in undergraduate physical chemistry was specifically developed for a pharmacy bachelor degree program. The starting point of this PBL was an open-ended question that is close to the student scientist’s interest and...

Herein we describe the preparation of hybrid polymer–inorganic interfaces by the immobilization of polyoxometalate nanoclusters on functionalized polymer surfaces. The polymeric surfaces were made of polystyrene-b-poly(acrylic acid)/polystyrene (PS-b-PAA/PS) blends by spin coating on a silicon wafer. The functionalization of the polymer film was ob...

Poly(2-ethyl-2-oxazoline) has become an excellent alternative to the use of poly(ethylene glycol) in pharmaceutical formulations due to its valuable physicochemical and biological properties. This work presents a formulation of poorly-water soluble drug, hydrocortisone, using interpolymer complexes and physical blends of poly(2-ethyl-2-oxazoline)s...

The demarcation of municipalities is essential for an adequate functioning of local administrations and the exercise of other public functions, such as jurisdiction, spatial planning, and urbanism. This research emphasizes the definition of municipalities in coastal areas, understanding that the beaches and the maritime-terrestrial zones are part o...

In this work we show an optical fiber evanescent wave absorption probe for glucose detection in different physiological media. High selectivity is achieved by functionalizing the surface of an only-core poly(methyl methacrylate) (PMMA) polymer optical fiber with phenilboronic groups, and enhanced sensitivity by using a U-shaped geometry. Employing...

This manuscript reports on the fabrication of silk fibroin (SF)-based magnetic electrospun fiber composites as scaffolds for tissue engineering applications. The magnetic responsiveness of the SF composite fibers was achieved by the inclusion of cobalt ferrite (CoFe2O4) or magnetite (Fe3O4) nanoparticles prior to processing the fibers via electrosp...

Material berrien eskaera handia dago biomedikuntza arloan inplante moduan erabiltzeko, baina errefus arazoak sortzen dituzte biobateragarritasun arazoak direla eta. Lan honetan bi motako substratuen (ez-organiko eta polimeriko) gainazala eraldatuko da geruz- geruzeko (“layer by layer” LbL) estrategiaz baliatuz, azido hialuroniko eta kitosanozko mul...

Paketatze-industrian jatorri petrokimikoa duten polimeroak ordezkatzeko, biopolimeroak gero eta gehiago erabiltzen dira. Poliazido laktikoaren L-isomeroak (PLLA) zink oxido (ZnO) nanopartikulekin nahastean elikagai industrian paketatzeko material moduan erabiltzeko ezaugarri onak aurkezten ditu. ZnO nanopartikulek bakterioen aurkako portaera erakus...