Solubility, bioavailability, permeation, polymorphism, and stability concerns associated to solid-state pharmaceuticals demand for effective solutions. To overcome some of these drawbacks, ionic ...liquids (ILs) have been investigated as solvents, reagents, and anti-solvents in the synthesis and crystallization of active pharmaceutical ingredients (APIs), as solvents, co-solvents and emulsifiers in drug formulations, as pharmaceuticals (API-ILs) aiming liquid therapeutics, and in the development and/or improvement of drug-delivery-based systems. The present review focuses on the use of ILs in the pharmaceutical field, covering their multiple applications from pharmaceutical synthesis to drug delivery. The most relevant research conducted up to date is presented and discussed, together with a critical analysis of the most significant IL-based strategies in order to improve the performance of therapeutics and drug delivery systems.
A shift to a bioeconomy development model has been evolving, conducting the scientific community to investigate new ways of producing chemicals, materials and fuels from renewable resources, i.e., ...biomass. Specifically, technologies that provide high performance and maximal use of biomass feedstocks into commodities with reduced environmental impact have been highly pursued. A key example comprises the extraction and/or dissolution of polysaccharides, one of the most abundant fractions of biomass, which still need to be improved regarding these processes' efficiency and selectivity parameters. In this context, the use of alternative solvents and the application of less energy-intensive processes in the extraction of polysaccharides might play an important role to reach higher efficiency and sustainability in biomass valorization. This review debates the latest achievements in sustainable processes for the extraction of polysaccharides from a myriad of biomass resources, including lignocellulosic materials and food residues. Particularly, the ability of ionic liquids (ILs) and deep eutectic solvents (DESs) to dissolve and extract the most abundant polysaccharides from natural sources, namely cellulose, chitin, starch, hemicelluloses and pectins, is scrutinized and the efficiencies between solvents are compared. The interaction mechanisms between solvent and polysaccharide are described, paving the way for the design of selective extraction processes. A detailed discussion of the work developed for each polysaccharide as well as the innovation degree and the development stage of dissolution and extraction technologies is presented. Their advantages and disadvantages are also identified, and possible synergies by integrating microwave- and ultrasound-assisted extraction (MAE and UAE) or a combination of both (UMAE) are briefly described. Overall, this review provides key information towards the design of more efficient, selective and sustainable extraction and dissolution processes of polysaccharides from biomass.
Hydrogen is a clean energy carrier and fuel cells (FCs) are an efficient conversion technology, and thus have become mainstream research topics that could contribute to sustainable and clean energy ...supply in modern society. Among the various hydrogen FC types that convert chemical energy into electrical energy
via
redox reactions, polymer electrolyte fuel cells (PEFCs) are the most studied technology due to their vast range of applications both mobile and stationary. The use of bio-based materials as substrates for the manufacture of the key constituent components of FCs, to minimize the impact of their production, although in its infancy, is growing exponentially as part of the general concern for sustainability. In fact, natural polymers such as cellulose (
i.e
. the most abundant biopolymer), and in particular its nanoscale forms,
viz
. cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs) and bacterial nanocellulose (BNC), are appropriate materials to engineer the key components of PEFCs, namely the ion-exchange membrane and the catalyst layer (anode and cathode). Despite the intense R&D activity, little has been reviewed about the potential application of these three forms of cellulose with at least one dimension in the nanoscale in the field of FCs. Hence, the overarching goal of this review is to concentrate on the most recent efforts in the domain of bio-based PEFC components, namely the ion-exchange membrane and the electrodes, by targeting the use of nanocellulose as a renewable and easily foldable or stackable nanomaterial. The application of these nanocellulose-based components in microbial fuel cells (MFCs) is also covered.
The present review article ventures into the question "Do the nanoscale forms of cellulose have potential in fuel cell systems?"
In the skin care field, bacterial nanocellulose (BNC), a versatile polysaccharide produced by non-pathogenic acetic acid bacteria, has received increased attention as a promising candidate to replace ...synthetic polymers (e.g., nylon, polyethylene, polyacrylamides) commonly used in cosmetics. The applicability of BNC in cosmetics has been mainly investigated as a carrier of active ingredients or as a structuring agent of cosmetic formulations. However, with the sustainability issues that are underway in the highly innovative cosmetic industry and with the growth prospects for the market of bio-based products, a much more prominent role is envisioned for BNC in this field. Thus, this review provides a comprehensive overview of the most recent (last 5 years) and relevant developments and challenges in the research of BNC applied to cosmetic, aiming at inspiring future research to go beyond in the applicability of this exceptional biotechnological material in such a promising area.
Motivated by the general concern about sustainability and environmental issues, an intense search for renewable-based polymers has grown exponentially in recent years. This search definitely ...spotlighted polyesters derived from 2,5-furandicarboxylic acid, among other polymers, as some of the most promising, especially due to the resemblance of this renewable monomer to the well-known petroleum-based terephthalic acid, as well as owing to the possibility of preparing innovative materials. The huge number of recent papers and patents about this family of polymers explore aspects as diverse as synthesis with other renewable-based monomers, leading to the preparation of materials with enhanced thermo-mechanical, biodegradability and liquid crystalline properties, among other features. Additional aspects pursued in such studies are innovation in the synthetic approaches or their optimisation, as well as the development of applications for everyday-life objects for example packaging materials, especially bottles, textiles, coating, and toners, among many other uses. Despite this intense activity, little has been reviewed recently about this unique family of polyesters or derived polymers, as the only reviews on the subject date back to the last century. In this perspective, the present review aims at contributing to filling this literature gap, covering recent aspects related with challenges in developing polyesters, polyamides, or other polymers from 2,5-furandicarboxylic acid and their precursors. Emphasis is placed on monomer synthesis, polymerisation reactions, catalysts and applications.
A tribute to 2,5-furandicarboxylic acid excellency and the myriad of novel polyesters, as well as polyamides, among other polycondensates, is comprehensively paid.
This study aimed to validate a food frequency questionnaire for foods high in sodium (FFQ-FHS) in a population aged ≥18 years and to test its reproducibility. This cross-sectional study included 50 ...individuals (≥18 years) of both sexes. In addition to the FFQ-FHS, four 24-h dietary recalls (24hRs) were conducted and a socioeconomic and lifestyle questionnaire was administered. Two 24-h urinary excretions were collected for sodium analysis, and anthropometry was performed. For validation, the triad method was applied using the validity coefficient (ρ). For reproducibility, the intraclass correlation coefficient (ICC), 95% confidence interval, kappa coefficient, and Bland-Altman plots were used to check for agreement. The Kolmogorov-Smirnov test was used to verify the data distribution. The validity coefficients for daily energy-adjusted sodium intake were high for the 24hR (ρRAI = 0.85) and weak for the FFQ-FHS (FFQAI = 0.26) and biomarker (ρBAI = 0.20). The ICC values were 0.68 for unadjusted sodium and 0.54 for energy-adjusted sodium intake. The weighed Kappa scores were 0.49 (p<0.01) and 0.260 (p = 0.02) for unadjusted and adjusted sodium intake, respectively. Although the FFQ-FHS is reproducible, it is not valid for the assessment of sodium intake and cannot be the sole instrument used for this purpose.
Natural polymers have emerged as promising candidates for the sustainable development of materials in areas ranging from food packaging and biomedicine to energy storage and electronics. In tandem, ...there is a growing interest in the design of advanced materials devised from naturally abundant and renewable feedstocks, in alignment with the principles of Green Chemistry and the 2030 Agenda for Sustainable Development. This review aims to highlight some examples of the research efforts conducted at the Research Team BioPol4fun, Innovation in BioPolymer-based Functional Materials and Bioactive Compounds, from the Portuguese Associate Laboratory CICECO-Aveiro Institute of Materials at the University of Aveiro, regarding the exploitation of natural polymers (and derivatives thereof) for the development of distinct sustainable biobased materials. In particular, focus will be given to the use of polysaccharides (cellulose, chitosan, pullulan, hyaluronic acid, fucoidan, alginate, and agar) and proteins (lysozyme and gelatin) for the assembly of composites, coatings, films, membranes, patches, nanosystems, and microneedles using environmentally friendly strategies, and to address their main domains of application.
Triterpenic acids (TTAs), known for their promising biological properties, can be found in different biomass sources and related by-products, such as
bark, and have been extracted using organic ...volatile solvents such as dichloromethane. Recently, deep eutectic solvents (DES) have been identified as promising alternatives for the extraction of value-added compounds from biomass. In the present work, several hydrophobic DES were tested for the extraction of TTAs from
bark. Initial solubility studies revealed that DES based on menthol and thymol as the most promising solvents for these compounds given the highest solubilities obtained for ursolic acid (UA) at temperatures ranging from room temperature up to 90 °C. Accordingly, an eutectic mixture of menthol:thymol (1:2) was confirmed as the best candidate for the TTAs extraction from
outer bark, leading to extraction yields (weight of TTA per weight of biomass) at room temperature of 1.8 wt% for ursolic acid, 0.84 wt% for oleanolic acid and 0.30 wt% for betulinic acid. These values are significantly higher than those obtained with conventional organic solvents under similar conditions. The results obtained using these DES are promising for the recovery of TTAs for nutraceutical and pharmacological applications, while reinforcing the potential of DES as promising solvents to be applied in biorefinery processes.
Betulinic acid (BA) and its natural analogues betulin (BN), betulonic (BoA), and 23-hydroxybetulinic (HBA) acids are lupane-type pentacyclic triterpenoids. They are present in many plants and display ...important biological activities. This review focuses on the chemical transformations used to functionalize BA/BN/BoA/HBA in order to obtain new derivatives with improved biological activity, covering the period since 2013 to 2018. It is divided by the main chemical transformations reported in the literature, including amination, esterification, alkylation, sulfonation, copper(I)-catalyzed alkyne-azide cycloaddition, palladium-catalyzed cross-coupling, hydroxylation, and aldol condensation reactions. In addition, the synthesis of heterocycle-fused BA/HBA derivatives and polymer‒BA conjugates are also addressed. The new derivatives are mainly used as antitumor agents, but there are other biological applications such as antimalarial activity, drug delivery, bioimaging, among others.
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