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1
Multimodal ionic liquid-based chromatographic supports for an effective RNA purification
Publicationby Carapito, Ana Rita MugeiroOther Authors: Bernardo, Sandra C.; Pereira, Matheus M.; Neves, Márcia C.; Freire, Mara G.; Sousa, FaniOrigin: uBibliorumNucleic acids have been considered interesting molecules to be used as biopharmaceuticals for the treatment of various diseases, in gene therapy strategies. In particular, RNA arises as the most promising approach because it does not require access to the nucleus of cells to exert its function; however, it is quite challenging due to its labile nature. To increase the possibility of translating RNA-based technology to clinical protocols, the bio- manufacturing of RNAs has been intensively exploited in the last few years. However, the standard RNA puri- fication processes remain time-consuming and present limitations regarding recovery yield and purity. This work describes the functionalization of chromatographic silica-based supports with four ionic liquids (ILs) composed of functional moieties that can promote distinct interactions with nucleic acids. After an initial screening to evaluate the binding and elution behavior of nucleic acids in the IL-based supports, SSi[C3C3NH2Im]Cl has shown to be the most promising for further purification assays. This support was studied for the RNA purification from different samples (clarified or more complex) and has shown to be highly effective, for all the conditions studied. Generally, it is here presented a new method for RNA isolation in a single step, using an IL-based chromato- graphic support, able to eliminate the usage of hazardous compounds often included in standard RNA extraction protocols. -
2
Multimodal ionic liquid-based chromatographic supports for an effective RNA purification
Publicationby Carapito, Ana RitaOther Authors: Bernardo, Sandra C.; Pereira, Matheus M.; Neves, Márcia C.; Freire, Mara; Sousa, FaniOrigin: uBibliorumNucleic acids have been considered interesting molecules to be used as biopharmaceuticals for the treatment of various diseases, in gene therapy strategies. In particular, RNA arises as the most promising approach because it does not require access to the nucleus of cells to exert its function; however, it is quite challenging due to its labile nature. To increase the possibility of translating RNA-based technology to clinical protocols, the biomanufacturing of RNAs has been intensively exploited in the last few years. However, the standard RNA purification processes remain time-consuming and present limitations regarding recovery yield and purity. This work describes the functionalization of chromatographic silica-based supports with four ionic liquids (ILs) composed of functional moieties that can promote distinct interactions with nucleic acids. After an initial screening to evaluate the binding and elution behavior of nucleic acids in the IL-based supports, SSi[C3C3NH2Im]Cl has shown to be the most promising for further purification assays. This support was studied for the RNA purification from different samples (clarified or more complex) and has shown to be highly effective, for all the conditions studied. Generally, it is here presented a new method for RNA isolation in a single step, using an IL-based chromatographic support, able to eliminate the usage of hazardous compounds often included in standard RNA extraction protocols. -
3
Triblock copolymers as versatile constituents of double stimuli-responsive ionic-liquid-based aqueous biphasic systems
Publicationby Rufino, Ana F. C. S.Other Authors: Ribeiro, Sara C.; Coutinho, João A. P.; e Silva, Francisca A.; Freire, Mara G.This work proposes the use of triblock copolymers as structurally versatile constituents to develop double stimuli-responsive aqueous biphasic systems (ABS) comprising ionic liquids (ILs). Phase diagrams of ABS comprising cholinium acetate ([Ch][C2O2]) and triblock copolymers composed of polyethylene oxide (PEO) and polypropylene oxide (PPO) with adjustable compositions of PEO, 20% (PE 6200) and 40% (PE 6400), were determined by the cloud point titration method at several temperatures (25–45 °C) and pH (5–7). These ABS present, for all the tested pH conditions, a Lower Critical Solution Temperature (LCST)-like behavior. However, only ABS with PE 6400 copolymer exhibit a simultaneous response to both stimuli. Compared to the homologous homopolymer polypropylene glycol (PPG), and despite their lower capacity to form ABS, copolymers with an adequate content of PEO provide a stronger response to the simultaneous action of pH and temperature. The results obtained highlight the value of an appropriate adjustment of the polymer structure/monomer composition in the development of ABS with double response to temperature and pH. The enhanced tailoring ability of the proposed systems is demonstrated with the simultaneous separation of two dyes by the application of the studied stimuli. -
4
Double-Stimuli-Responsive (Temperature and pH) Aqueous Biphasic Systems Comprising Ionic Liquids
Publicationby Rufino, Ana F. C. S.Other Authors: Bola, Joana M.; Capela, Emanuel V.; Coutinho, João A. P.; e Silva, Francisca A.; Freire, Mara G.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. Resorting to choline-alkanoate-based ILs as the pH-responsive components and poly(propylene glycol) (PPG 400) as the thermo-responsive component, the ABS ternary phase diagrams are determined at various temperature (25–45 °C) and pH (3–7) conditions. While the liquid–liquid phase diagram response to temperature obeys a lower critical solution temperature-like behavior, the response to pH correlates with the pKa of the IL anion parent acid. The simultaneous responsiveness to temperature and pH is then shown, whose results inspire the development of customizable separation techniques as proved with the simultaneous (one-step) separation of two dyes. By a proper customization of the IL chemical structure and stimuli applied, ABS may be designed to improve the performance and sustainability of separation processes. -
5
Recombinant membrane protein production using integrated strategies
Publicationby Fernandes, João Luís PereiraMembrane proteins (MP) are a crucial part for the discovery of new drugs, which requires structural and functional studies. For these studies, high amounts of high-quality (pure and active) MP are needed. Despite their importance, MP production is still challenged by their hydrophobic nature, with the process being lengthy and requiring complex downstream processing steps. Ionic liquids (ILs) can be a promising alternative for MP production, allowing for the integration of different processing steps, such as cell lysis and MP solubilization. As such, the goal of this work was to study the ability of several ILs to cause lysis of Komagataella pastoris cells, while simultaneously solubilizing the enzyme cyclooxygenase 2 (COX-2), used in this work as a model MP. The inhibition of this enzyme is therapeutically relevant due to its role in inflammatory processes. Another goal was the usage of the activity coefficient model Conductor-like screening model for realistic solvents (COSMO-RS) to study the interactions between IL and the components of the yeast cell membrane and wall, possibly creating a model to screen ILs with respect their ability to cause cell lysis. Among the investigated ILs, protic ILs based on the N,N-diethylethanolammonium cation combined with carboxylic acids, as anions, proved promising in both lysing the yeast cells and solubilizing COX-2. A sample pre-treatment method based on ultrafiltration was also developed that allows to partially remove IL interference on protein quantification methods, allowing for more accurate quantifications. Simultaneously, promising correlations were found between experimental data and COSMO-RS, with the misfit and van der Waals interactions being relevant to the cell lysis process. After the optimization of COX-2 extraction parameters, the study and development of an aqueous biphasic systems as an extraction and separation process, is proposed as future work for the initial clarification of COX-2. To sum up, it is expected that the approach herein presented will be an important step forward toward the creation of an effective and low-cost process for the production of high-quality MP. Furthermore, the potential of protic IL to simultaneously lyse yeast cells and solubilize MP is reported for the first time. -
6
Multimodal ionic liquid-based chromatographic supports for an effective RNA purification
Publicationby Carapito, RitaOther Authors: Bernardo, Sandra C.; Pereira, Matheus M.; Neves, Márcia C.; Freire, Mara G.; Sousa, FaniNucleic acids have been considered interesting molecules to be used as biopharmaceuticals for the treatment of various diseases, in gene therapy strategies. In particular, RNA arises as the most promising approach because it does not require access to the nucleus of cells to exert its function; however, it is quite challenging due to its labile nature. To increase the possibility of translating RNA-based technology to clinical protocols, the biomanufacturing of RNAs has been intensively exploited in the last few years. However, the standard RNA purif ication processes remain time-consuming and present limitations regarding recovery yield and purity. This work describes the functionalization of chromatographic silica-based supports with four ionic liquids (ILs) composed of functional moieties that can promote distinct interactions with nucleic acids. After an initial screening to evaluate the binding and elution behavior of nucleic acids in the IL-based supports, SSi[C 3 C 3NH2 Im]Cl has shown to be the most promising for further purification assays. This support was studied for the RNA purification from different samples (clarified or more complex) and has shown to be highly effective, for all the conditions studied. Generally, it is here presented a new method for RNA isolation in a single step, using an IL-based chromatographic support, able to eliminate the usage of hazardous compounds often included in standard RNA extraction protocols. -
7
Desulfurization of liquid fuels by extraction and sulfoxidation using H2O2 and [CpMo(CO)3R] as catalysts
Publicationby Julião, DianaOther Authors: Gomes, Ana C.; Pillinger, Martyn; Valença, Rita; Ribeiro, Jorge C.; Gonçalves, Isabel S. et al.Efficient and recyclable liquid–liquid extraction and catalytic oxidative desulfurization (ECODS) systems for the removal of refractory sulfur compounds from liquid fuels are reported that use the cyclopentadienyl molybdenum tricarbonyl complexes [CpMo(CO)3Me] (1), [CpMo(CO)3(CH2-pC6H4-CO2Me] (2) and [CpMo(CO)3CH2COOH] (3) as catalyst precursors. An ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate, was used as both extractant and reaction medium, entrapping the active homogeneous MoVI catalysts that are formed in situ under the operating catalytic conditions (aqueous H2O2 as oxidant, 50 °C). The high sulfoxidation activity of the catalyst formed from 1 was largely responsible for enabling >99% desulfurization within 1 h of a model oil containing 1-benzothiophene, dibenzothiophene, 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene (2000 ppm S). The IL/catalyst phase could be repeatedly recycled with no loss of desulfurization efficiency. By sequentially performing extractive desulfurization and ECODS steps, 83–84% sulfur removal was achieved for untreated real diesel and jet fuel samples with initial sulfur contents of ca. 2300 and 1100 ppm, respectively. -
8
Insights into coacervative and dispersive liquid-phase microextraction strategies with hydrophilic media - a review
Publicationby Pacheco-Fernández, IdairaOther Authors: González-Martín, Raúl; Silva, Francisca A. e; Freire, Mara G.; Pino, VerónicaSince the development of liquid-phase microextraction (LPME), different LPME modes depending on the experimental set-up to carry out the extraction have been described. Dispersive liquid-liquid microextraction (DLLME), in which a small amount of the water-insoluble extraction solvent is dispersed in the sample, is the most successful mode in terms of number of applications reported. Advances within DLLME have been mainly shifted to the incorporation of green, smart and tunable materials as extraction solvents to improve the sustainability and efficiency of the method. In this sense, hydrophilic media represent a promising alternative since the water-miscibility of these substances increases the mass transfer of the analytes to the extraction media, leading to higher extraction efficiencies. Considering the variety of hydrophilic media that have been incorporated in LPME approaches resembling DLLME, this review aims to classify these methods in order to clarify the confusing terminology used for some of the strategies. Hydrophilic media covered in this review comprise surfactants, polar organic solvents, deep eutectic solvents, ionic liquids, water-miscible polymers, and switchable solvents. Different physicochemical mechanisms of phase separation are discussed for each LPME method, including the coacervation phenomena and other driving forces, such as pH, temperature, salting-out effect, metathesis reaction and organic solvents. LPME modes are classified (in cloud-point extraction, coacervative extraction, aqueous biphasic systems, and different DLLME modes depending on the extraction medium) according to both the nature of the water-miscible extraction phase and the driving force of the separation. In addition, the main advances and analytical applications of these methods in the last three years are described. -
9
Simultaneous morphological transformation of metal salt and conformations of DNA in a bio-based ionic liquid
Publicationby Bhatt, JitkumarOther Authors: Pereira, Matheus M.; Prasad, KamaleshThe extraordinary left handed conformation of DNA known as Z-DNA has attracted the attention of structural biologists due to its characteristic features such as its possible role in regulation of gene expression and genetic instability. There are number of physical parameters which can induce the conformational transformation of double helical B-DNA to Z-DNA. Among the various physical conditions, right-handed B-DNA can be transformed into left-handed Z-DNA in vitro at high salt concentrations or in vivo under physiological conditions. Herein DNA solubilized in a choline based ionic liquid namely choline formate was found to reduce Ag(I) salt into silver nanoparticles (AgNPs) with the size distribution of 10-20 nm. During the process, the interaction of DNA with the ionic liquid induces alteration in secondary structure of DNA (B-Z transition). The formation of the NPs was confirmed by UV-Vis spectrophotometer and Transmission Electron Microscopic (TEM) measurements, while the formation of Z-DNA was confirmed by circular dichroism (CD) spectroscopic measurements. Upon molecular docking studies, choline-formate was found to present different binding sites for its cation and anion and they promote torsions on DNA structure leading to possible changes in DNA three dimensional structures (B-Z transition). -
10
Recovery of nonsteroidal anti-inflammatory drugs from wastes using ionic-liquid-based three-phase partitioning systems
Publicationby e Silva, Francisca A.Other Authors: Caban, Magda; Kholany, Mariam; Stepnowski, Piotr; Coutinho, João A. P.; Ventura, Sónia P. M.Aiming at outlining new strategies for the valorization of solid pharmaceutical wastes as viable alternatives to incineration, this work proposes the use of ionic liquids-based three phase partitioning (IL-based TPP) systems. Ibuprofen, naproxen, and ketoprofen, all belonging to the class of nonsteroidal anti-inflammatory drugs (NSAIDs), were adopted as model compounds. An integrated process has been conceptualized based on three steps: (1) extraction and purification of NSAIDs using the IL-based TPP systems, (2) drug isolation by precipitation with antisolvents, and (3) recycling and reusing the solvents. With the optimization of steps 1 and 2 as objects of this investigation, aqueous biphasic systems (ABS) composed of three distinct ILs (tetrabutylammonium chloride, 1-butyl-3-methylimidazolium chloride, and benzyldimethyl(2-hydroxyethyl)ammonium chloride) and potassium citrate buffer were studied. The corresponding IL-based TPP systems were further applied in the purification of each NSAID, and different antisolvents (citric acid aqueous solutions for ibuprofen and naproxen and aluminum sulfate aqueous solutions for ketoprofen) were evaluated as precipitating agents to isolate each drug. The success of the process developed is demonstrated by extraction efficiencies higher than 83.8 ± 7.7% attained in step 1 and isolation efficiencies higher than 76.2 ± 1.8% in step 2. The stability of the three NSAIDs in IL-based aqueous matrices was additionally checked by using a protocol adapted from the OECD guidelines. The economic efficiency and environmental benignity of the process herein developed is underlined, based on not only the low cost of the solvents chosen but also the possibility of recycling and reusing the phase-forming components and antisolvents employed.
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