Mara G Freire

University of Aveiro | UA · CICECO - Aveiro Institute of Materials

Theaflavins, powerful antioxidants found in black tea ( Camellia sinensis ), have garnered increasing interest for their promising therapeutic potential. Experimental studies have contributed to enlightening about the advantages of theaflavins, including their antioxidant, anti‐inflammatory, anticancer, antiosteoporosis, and antimicrobial propertie...

Herein we demonstrate the formation of new stimuli‐responsive aqueous biphasic systems (ABS), able to respond simultaneously to temperature and pH, or just to one stimulus, therefore allowing the design of more sustainable separation processes. This dual behavior is achieved with ABS formed by mono‐ or dicationic protic ionic liquids as phase‐formi...

The evolution of the electric vehicle market and the ongoing demand for lithium (Li), cobalt (Co) and nickel (Ni) for batteries production requires secondary sources for obtaining these elements. The recycling of Li‐ion batteries involves hydrometallurgical processes with potential environmental implications, hence there is an urgent need for susta...

We propose an innovative approach to address the pressing need for efficient and transparent evaluation techniques to assess extraction processes’ sustainability.

Poultry is a widely consumed meat worldwide; however, its industrial processing generates a significant amount of feather waste. Since the major component of chicken feathers is keratin (90 wt%), this study focused on using acetate-based ionic liquids (ILs) to fully dissolve chicken feathers and recover keratin, using a sustainable and cost-effecti...

Amyloid-like fibrils are garnering keen interest in biotechnology as supramolecular nanofunctional units to be used as biomimetic platforms to control cell behavior. Recent insights into fibril functionality have highlighted their importance in tissue structure, mechanical properties, and improved cell adhesion, emphasizing the need for scalable an...

Free access until July 13, 2024: https://authors.elsevier.com/c/1j8nH7taLYXPi2

Enzyme immobilization can offer a range of significant advantages, including reusability, and increased selectivity, stability, and activity. In this work, a central composite design (CCD) of experiments and response surface methodology (RSM) were used to study, for the first time, the L‐asparaginase (ASNase) immobilization onto functionalized carb...

Proteins are highly labile molecules, thus requiring the presence of appropriate solvents and excipients in their liquid milieu to keep their stability and biological activity. In this field, ionic liquids (ILs) have gained momentum in the past years, with a relevant number of works reporting their successful use to dissolve, stabilize, extract, an...

Artemisinin, a drug used to treat malaria, can be chemically synthesized or extracted from Artemisia annua L. However, the extraction method for artemisinin from biomass needs to be more sustainable while maintaining or enhancing its bioactivity. This work investigates the use of aqueous solutions of salts and ionic liquids with hydrotropic propert...

Bisphenols, and mostly bisphenol A (BPA), are widely used in many consumer products. Due to their toxicity, BPA presents a noteworthy risk to the environment and human health. Despite these...

Platinum (Pt) and palladium (Pd) are considered critical elements due to their scarcity and high demand for important technologies, namely, in automotive catalytic converters. Therefore, sustainable technologies that are able to selectively extract such metals from secondary sources are extremely important. This work focuses on the preparation and...

Surtos, epidemias e pandemias são responsáveis por grandes alterações económicas, políticas, e sociais, permitindo igualmente um elevado desenvolvimento científico e tecnológico. Ao longo da história, estes eventos têm-se vindo a intensificar devido ao aumento na mobilidade entre populações, o que se traduz num aumento das cadeias de transmissão de...

Advances towards the development of a sustainable economy must address the exploitation of bio-based products combined with the use of greener solvents and manufacturing processes that can preserve natural resources and the environment. To address the growing demand for proteins, their production must focus on non-animal sources, such as vegetal bi...

Antimicrobial photodynamic therapy (aPDT) is a potent tool to surpass the global rise of antimicrobial resistance; still, the effective topical administration of photosensitizers remains a challenge. Biopolymer-based adhesive films can safely extend the residence time of photosensitizers. However, their wide application is narrowed by their limited...

Anthropogenic impacts have affected the coastal environment and contributed to its contamination. Mercury (Hg) is widespread in nature and has been shown to be toxic in even the smallest amounts, negatively affecting not only the marine ecosystem but also the entire trophic chain due to its biomagnification. Mercury ranks third on the Agency for To...

[This corrects the article DOI: 10.3389/fbioe.2023.1037436.].

Aqueous biphasic systems (ABS) can integrate multiple unit operations and operate under continuous mode, contributing to the development of sustainable separation processes. Encouraged by the designer solvent features of ionic liquids (ILs), we herein propose their use as components of double-stimuli-responsive (temperature- and pH-driven) ABS. Res...

The consumption of cytostatics, pharmaceuticals prescribed in chemotherapy, is increasing every year and worldwide, along with the incidence of cancer. The presence and the temporal evolution of cytostatics in wastewaters from a Portuguese hospital center was evaluated through a 9-month sampling campaign, comprising a total of one hundred and twent...

The rise of antibiotic resistant strains, as methicillin‐resistant Staphylococcus aureus (MRSA), challenges the current treatment of infections. In the case of ocular infections, antibiotic eye drops are commonly prescribed. However, their efficacy is usually compromised by the low viscosity of these formulations and the eye drainage. To overcome t...

Prostate cancer (PCa) is one of the cancer types that most affects males worldwide and is among the highest contributors to cancer mortality rates. Therefore, there is an urgent need to find strategies to improve the diagnosis of PCa. Microtechnologies have been gaining ground in biomedical devices, with microfluidics and lab-on-chip systems potent...

The emergence of biopharmaceuticals, including proteins, nucleic acids, peptides, and vaccines, revolutionized the medical field, contributing to significant advances in the prophylaxis and treatment of chronic and life-threatening diseases. However, biopharmaceuticals manufacturing involves a set of complex upstream and downstream processes, which...

Aqueous biphasic systems (ABSs) based on sodium polyacrylate (NaPA), ethylene oxide/propylene oxide (EO/PO) polymers, and (EO)x-(PO)y-(EO)x triblock copolymers were prepared and applied aiming at continuous fructooligosaccharide (FOS) production and separation. EO/PO hydrophilicity/hydrophobicity balance had a significant effect on ABS formation. T...

Deep Eutectic solvent as a suitable solvent system to design a final pharmaceutical formulation of immunoglobulin G antibodies.

The poultry-processing industry generates large quantities of waste rich in keratin, a fibrous protein representing around 90 wt % of chicken feathers, which is currently disposed of in landfilling or...

An integrated extraction–separation process: extraction and selective separation of chlorophylls and betalains using thermoreversible aqueous biphasic systems.

Keratin is a biopolymer with high potential for biomaterials production, being principally investigated in hydrogel and film forms for use in tissue-engineering applications. Aiming to find sustainable solvents and develop...

Ionic liquid-based aqueous biphasic systems succeed in one-step clean-up, microextraction, and preconcentration strategies for biomarkers in saliva. These novel platforms improve the saliva bioanalysis in terms of simplicity and greenness.

Polydopamine (PDA), a bioinspired polymer from mussel adhesive proteins, has attracted impressive attention as a novel coating for (nano) materials with an adequate conformal layer and adjustable thickness. Currently, PDA is obtained from dopamine chemical oxidation under alkaline conditions, limiting its use in materials sensible to alkaline envir...

According to the European Environment Agency, the textile industry is responsible for 20% of global water pollution due to dyeing and finishing products, thus facing severe environmental challenges. It is essential to design more biocompatible and sustainable treatment processes capable of removing dyes from industrial wastewater to fight this envi...

Nanomaterials have been extensively used in different applications due to their peculiar characteristics and nanoscale dimensions. Among nanoparticles, carbon-based nanomaterials are becoming highly attractive for biomedical applications such as diagnosis, tissue engineering, drug delivery, and biosensing. The conjugation of carbon-based nanomateri...

Given the growing number of cancer diseases, new cytostatic drugs are approved daily, often with concomitant development, or refinement of some of these drugs aimed at decreasing patient discomfort during the administration period (e.g., prodrugs). Classified as highly toxic, they represent a major environmental problem that may potentiate disease...

Over the past few years, antibodies such as immunoglobulin G, IgG, have increased their market share as alternative therapeutics. However, their production at high purity levels is still costly due to the absence of a cost-effective platform for their recovery and purification from the complex biological media in which they are produced. This work...

Biocatalytic processes find increasing applications in various industries due to the high efficiency of biotransformations as well as the renewable nature of the enzymes and substrates. Enzymatic biocatalysis is an attractive alternative to conventional chemical catalysis, with corresponding advances now allowing a wide range of biotransformations....

L-asparaginase (ASNase, EC 3.5.1.1) is an amidohydrolase enzyme known for its anti-cancer properties, with an ever-increasing commercial value. Immobilization has been studied to improve the enzyme’s efficiency, enabling its recovery and reuse, enhancing its stability and half-life time. In this work, the effect of pH, contact time and enzyme conce...

Cancer remains the cause of millions of deaths every year worldwide, and reliable early-stage diagnosis methods are essential to prevent them. Cancer biomarkers quantification in human fluids has gained relevance in detecting cancer in an early-stage. Among these, the levels of the biomarkers epinephrine, norepinephrine and vanillylmandelic acid in...

This review summarizes and critically addresses the advances achieved on the processing of biomaterials, namely films, scaffolds, and nanoparticles, using ionic liquids as alternative solvents. Biomaterials composed of proteins, polysaccharides, and their blends are here considered. Despite their relevance, the low solubility of these compounds in...

Modern societies produce large amounts of waste of many different types. This presents a problem in terms of management or disposal to prevent harm to human health and the environment. Additionally it represents a loss of potentially useful resources. In the circular economy concept nothing would ever become waste because everything would be re-usa...

Currently, the use of alternative solvents is increasing, namely ionic liquids (ILs) and deep eutectic solvents (DESs) in diverse fields of knowledge, such as biochemistry, chemistry, chemical engineering, biotechnology and biomedicine. Particularly, when compared to traditional solvents, these alternative solvents have great importance for biomole...

Although their high potential as alternative biopharmaceuticals, less than 2% of the total polyclonal antibodies produced worldwide correspond to immunoglobulin Y (IgY) due to the difficulties in isolating them from egg yolk that is a complex biological matrix. In this work, the proteins water soluble fraction (WSPF) of egg yolk was first obtained...

Artemisinin is an antimalarial substance very sparingly soluble in water. In the attempt to identify environmental-friendly and non-toxic aqueous-based solvents to extract it from Artemisia annua L., the solubility of artemisinin in aqueous solutions of different hydrotropes was measured at 303.2 K, for hydrotrope concentrations up to 5 M. The abil...

Compartmentalized structures obtained in all‐aqueous settings have shown promising properties as cell encapsulation devices, as well as reactors for trans‐membrane chemical reactions. While most approaches focus on the preparation of spherical devices, advances on the production of complex architectures have been enabled by the interfacial stabilit...

The purification of value-added compounds by three-phase partitioning (TPP) is a promising alternative to conventional processes since the target compound can be easily recovered from the liquid-liquid interphase. Although this technique has been successfully applied to the recovery of proteins, the minimization of the use of salts and solvents mus...

L-asparaginase (ASNase) is an aminohydrolase currently used in the pharmaceutical and food industries. Enzyme immobilization is an exciting option for both applications, allowing for a more straightforward recovery and increased stability. High surface area and customizable porosity make carbon xerogels (CXs) promising materials for ASNase immobili...

The transdermal administration of nonsteroidal anti-inflammatory drugs (NSAIDs) is a valuable and safer alternative to their oral intake. However, most of these drugs display low water solubility, which makes their incorporation into hydrophilic biopolymeric drug-delivery systems difficult. To overcome this drawback, aqueous solutions of bio-based...

L-asparaginase (ASNase) is an aminohydrolase currently used in the pharmaceutical and food industries. Enzyme immobilization is an exciting option for both applications, allowing a more straightforward recovery and increased stability. High surface area and customizable porosity make carbon xerogels (CXs) promising materials for ASNase immobilizati...

Neonicotinoids are systemic insecticides commonly used for pest control in agriculture and veterinary applications. Due to their widespread use, neonicotinoid insecticides (neonics) are found in different environmental compartments, including water, soils, and biota, in which their high toxicity towards non-target organisms is a matter of great con...

Proteins are one the most widely studied biomolecules with diverse functions and applications. Aiming at overcoming the current drawbacks of purification processes of proteins, the introduction of ionic liquids (ILs) has been a hot topic of research. ILs have been applied in the creation of aqueous biphasic systems (IL-based ABS), solid-phase extra...