This page has only limited features, please log in for full access.
The development of novel green solvents demands the knowledge of their properties, such as polarity, which can be described through solvatochromic parameters. However, while these are available for a wide range of conventional solvents, there is a lack of data for the emergent ones. Considering the need for such data, predictive models to estimate the Kamlet–Taft (K–T) parameters for deep eutectic solvents (DES) are developed here. The models, based on the conductor-like screening model for real solvents (COSMO-RS) descriptors, were initially developed and tested for 175 organic solvents to validate the applicability of the proposed approach. This approach was then extended for DES, which were classified into two categories, acids and nonacids. The developed equations showed a very good performance for all three K–T parameters, and this is the first work to propose models for all K–T parameters for DES. Moreover, a comparison between polarity data of DES and organic compounds showed that DES, rather than replace common solvents, can extend their range of polarities, reinforcing their designer solvent ability.
José Pedro Wojeicchowski; Dinis O. Abranches; Ana M. Ferreira; Marcos R. Mafra; João A.P. Coutinho. Using COSMO-RS to Predict Solvatochromic Parameters for Deep Eutectic Solvents. ACS Sustainable Chemistry & Engineering 2021, 1 .
AMA StyleJosé Pedro Wojeicchowski, Dinis O. Abranches, Ana M. Ferreira, Marcos R. Mafra, João A.P. Coutinho. Using COSMO-RS to Predict Solvatochromic Parameters for Deep Eutectic Solvents. ACS Sustainable Chemistry & Engineering. 2021; ():1.
Chicago/Turabian StyleJosé Pedro Wojeicchowski; Dinis O. Abranches; Ana M. Ferreira; Marcos R. Mafra; João A.P. Coutinho. 2021. "Using COSMO-RS to Predict Solvatochromic Parameters for Deep Eutectic Solvents." ACS Sustainable Chemistry & Engineering , no. : 1.
Rutin is a known antioxidant compound that displays a broad range of biological activities and health-related benefits but presents a low water solubility that can be overcome by its polymerization. In this work, biocompatible aqueous biphasic systems composed of the ionic liquid cholinium dihydrogen phosphate ([CH][DHph]) and the polymer poly(ethylene glycol) 600 (PEG 600) were investigated as an efficient integrated reaction–separation platform for the laccase-catalyzed oligomerization of rutin. Two different approaches were studied to reuse laccase in several oligorutin production cycles, the main difference between them being the use of monophasic or biphasic regimes during the oligomerization reaction. The use of a biphasic regime in the second approach (heterogeneous reaction medium) allowed the successful reuse of the biocatalyst in three consecutive reaction–separation cycles while achieving noteworthy rutin oligomerization yields (95% in the first cycle, 91% in the second cycle, and 89% in the last cycle). These remarkable results were caused by the combination of the increased solubility of rutin in the PEG-rich phase together with the enhanced catalytic performance of laccase in the [Ch][DHph]-rich phase, alongside with the optimization of the pH of the reaction medium straightly linked to enzyme stability. Finally, a life-cycle assessment was performed to compare this integrated reaction–separation platform to three alternative processes, reinforcing its sustainability.
Abel Muñiz-Mouro; Ana M. Ferreira; João A. P. Coutinho; Mara G. Freire; Ana P. M. Tavares; Patricia Gullón; Sara González-García; Gemma Eibes. Integrated Biocatalytic Platform Based on Aqueous Biphasic Systems for the Sustainable Oligomerization of Rutin. ACS Sustainable Chemistry & Engineering 2021, 9, 9941 -9950.
AMA StyleAbel Muñiz-Mouro, Ana M. Ferreira, João A. P. Coutinho, Mara G. Freire, Ana P. M. Tavares, Patricia Gullón, Sara González-García, Gemma Eibes. Integrated Biocatalytic Platform Based on Aqueous Biphasic Systems for the Sustainable Oligomerization of Rutin. ACS Sustainable Chemistry & Engineering. 2021; 9 (29):9941-9950.
Chicago/Turabian StyleAbel Muñiz-Mouro; Ana M. Ferreira; João A. P. Coutinho; Mara G. Freire; Ana P. M. Tavares; Patricia Gullón; Sara González-García; Gemma Eibes. 2021. "Integrated Biocatalytic Platform Based on Aqueous Biphasic Systems for the Sustainable Oligomerization of Rutin." ACS Sustainable Chemistry & Engineering 9, no. 29: 9941-9950.
Spent coffee grounds (SCGs) are a waste product with no relevant commercial value. However, SCGs are rich in extractable compounds with biological activity. To add value to this coffee byproduct, water and aqueous solutions of cholinium-based ionic liquids (ILs) were studied to extract caffeine from SCGs. In general, all IL aqueous solutions lead to higher extraction efficiencies of caffeine than pure water, with aqueous solutions of cholinium bicarbonate being the most efficient. A factorial planning was applied to optimize operational conditions. Aqueous solutions of cholinium bicarbonate, at a temperature of 80 °C for 30 min of extraction, a biomass–solvent weight ratio of 0.05 and at an IL concentration of 1.5 M, made it possible to extract 3.29 wt% of caffeine (against 1.50 wt% obtained at the best conditions obtained with pure water). Furthermore, to improve the sustainability of the process, the same IL aqueous solution was consecutively applied to extract caffeine from six samples of fresh biomass, where an increase in the extraction yield from 3.29 to 13.10 wt% was achieved. Finally, the cholinium bicarbonate was converted to cholinium chloride by titration with hydrochloric acid envisioning the direct application of the IL-caffeine extract in food, cosmetic and nutraceutical products. The results obtained prove that aqueous solutions of cholinium-based ILs are improved solvents for the extraction of caffeine from SCGs, paving the way for their use in the valorization of other waste rich in high-value compounds.
Ana Ferreira; Hugo Gomes; João Coutinho; Mara Freire. Valorization of Spent Coffee by Caffeine Extraction Using Aqueous Solutions of Cholinium-Based Ionic Liquids. Sustainability 2021, 13, 7509 .
AMA StyleAna Ferreira, Hugo Gomes, João Coutinho, Mara Freire. Valorization of Spent Coffee by Caffeine Extraction Using Aqueous Solutions of Cholinium-Based Ionic Liquids. Sustainability. 2021; 13 (13):7509.
Chicago/Turabian StyleAna Ferreira; Hugo Gomes; João Coutinho; Mara Freire. 2021. "Valorization of Spent Coffee by Caffeine Extraction Using Aqueous Solutions of Cholinium-Based Ionic Liquids." Sustainability 13, no. 13: 7509.
Zwitterionic compounds are less ecotoxic than their analogous ionic liquids.
Fátima Jesus; Helena Passos; Ana M. Ferreira; Kosuke Kuroda; Joana Luísa Pereira; Fernando J. M. Gonçalves; João A. P. Coutinho; Sónia P. M. Ventura. Zwitterionic compounds are less ecotoxic than their analogous ionic liquids. Green Chemistry 2021, 23, 3683 -3692.
AMA StyleFátima Jesus, Helena Passos, Ana M. Ferreira, Kosuke Kuroda, Joana Luísa Pereira, Fernando J. M. Gonçalves, João A. P. Coutinho, Sónia P. M. Ventura. Zwitterionic compounds are less ecotoxic than their analogous ionic liquids. Green Chemistry. 2021; 23 (10):3683-3692.
Chicago/Turabian StyleFátima Jesus; Helena Passos; Ana M. Ferreira; Kosuke Kuroda; Joana Luísa Pereira; Fernando J. M. Gonçalves; João A. P. Coutinho; Sónia P. M. Ventura. 2021. "Zwitterionic compounds are less ecotoxic than their analogous ionic liquids." Green Chemistry 23, no. 10: 3683-3692.
Novel liquid supports for enzyme immobilization and reuse based on aqueous biphasic systems (ABS) constituted by cholinium‐based ionic liquids (ILs) and polymers for the degradation of dyes are here proposed. The biocatalytic reaction for dye decolorization using laccase occurs in the biphasic medium, with the enzyme being “supported” in the IL‐rich phase and the dye and degradation products being enriched in the polymer‐rich phase. An initial screening of the laccase activity in aqueous solutions of ABS constituents, namely cholinium dihydrogen citrate ([Ch][DHC]), cholinium dihydrogen phosphate ([Ch][DHP]), cholinium acetate ([Ch][Acet]), polypropylene glycol 400 (PPG 400), polyethylene glycol 400 (PEG 400) and K2HPO4 was carried out. Compared to the buffered control, a relative laccase activity of up to 170%, 257% and 530% was observed with PEG 400, [Ch][DHP] and [Ch][DHC], respectively. These ABS constituents were then investigated for the in situ enzymatic biodegradation of the Remazol Brilliant Blue R (RBBR) dye. At the optimized conditions, the ABS constituted PPG 400 at 46 wt% and [Ch][DHC] at 16 wt% leads to the complete degradation of the RBBR dye, further maintaining the enzyme activity. This ABS also allows an easy immobilization, recovery and reuse of the biocatalyst for six consecutive reaction cycles, achieving a degradation yield of the dye of 96% in the last cycle. In summary, if properly designed, high enzymatic activities and reaction yields are obtained with ABS as liquid supports, while simultaneously overcoming the safety and environmental concerns of conventional organic solvents used in liquid‐liquid heterogeneous reactions, thus representing more sustainable biocatalytic processes.
Ana M. Ferreira; Ana I. Valente; Leonor S. Castro; João A. P. Coutinho; Mara G. Freire; Ana P. M. Tavares. Sustainable liquid supports for laccase immobilization and reuse: Degradation of dyes in aqueous biphasic systems. Biotechnology and Bioengineering 2021, 118, 2514 -2523.
AMA StyleAna M. Ferreira, Ana I. Valente, Leonor S. Castro, João A. P. Coutinho, Mara G. Freire, Ana P. M. Tavares. Sustainable liquid supports for laccase immobilization and reuse: Degradation of dyes in aqueous biphasic systems. Biotechnology and Bioengineering. 2021; 118 (7):2514-2523.
Chicago/Turabian StyleAna M. Ferreira; Ana I. Valente; Leonor S. Castro; João A. P. Coutinho; Mara G. Freire; Ana P. M. Tavares. 2021. "Sustainable liquid supports for laccase immobilization and reuse: Degradation of dyes in aqueous biphasic systems." Biotechnology and Bioengineering 118, no. 7: 2514-2523.
Highly hydrophilic counterions such as sodium or chloride are not good choices as counterions to achieve efficient hydrotropy.
Dinis O. Abranches; Jordana Benfica; Bruna P. Soares; Ana M. Ferreira; Tânia E. Sintra; Seishi Shimizu; João A. P. Coutinho. The impact of the counterion in the performance of ionic hydrotropes. Chemical Communications 2021, 57, 2951 -2954.
AMA StyleDinis O. Abranches, Jordana Benfica, Bruna P. Soares, Ana M. Ferreira, Tânia E. Sintra, Seishi Shimizu, João A. P. Coutinho. The impact of the counterion in the performance of ionic hydrotropes. Chemical Communications. 2021; 57 (23):2951-2954.
Chicago/Turabian StyleDinis O. Abranches; Jordana Benfica; Bruna P. Soares; Ana M. Ferreira; Tânia E. Sintra; Seishi Shimizu; João A. P. Coutinho. 2021. "The impact of the counterion in the performance of ionic hydrotropes." Chemical Communications 57, no. 23: 2951-2954.
Trial and error remain the most common method to select the right solvent for the extraction of natural products, in particular when dealing with novel, poorly studied solvents such as deep eutectic solvents (DES). This can lead to either a lengthy or a suboptimal selection of solvents. COSMO-RS, a quantum chemistry-based thermodynamic model, was applied in this work to screen the best DES for the extraction of carnosic acid and carnosol, present in rosemary. Twenty-eight hydrogen bond acceptors (HBA) and forty-nine hydrogen bond donors (HBD) were selected for the initial computational evaluation that revealed that hydrophobic DES formed by ammonium chlorides as HBA, and the fatty acids, aromatic carboxylic acids or alcohols as HBD to be the most suitable solvents for this extraction. Then, solid-liquid extractions were performed using these solvents to identify the best one and to optimize its composition. The ability of the solvents to obtain an extract rich in carnosic acid and carnosol was measured by the antioxidant activity of the extract, being the mixture of 15 wt% of tetrapropylammonium chloride, 55 wt% of 1,2-propanediol and 30 wt% of water the solvent with the best performance. A response surface methodology was then carried out to optimize extraction conditions, in which antioxidant activity up to 85 mg TE/g dw, that correspond to the extraction of 14.8 mg of carnosic acid and 18.9 mg of carnosol /g dw. Finally, the antioxidant activity of extracts obtained from a solvent without HBA was investigated. These aqueous mixtures of 1,2-propanediol showed a small loss in the performance. However, since the extraction process is simplified and this alcohol is biocompatible and allowed in formulations, the binary mixture seems to be a good, more sustainable alternative, to the ternary one.
José Pedro Wojeicchowski; Ana M. Ferreira; Dinis O. Abranches; Marcos R. Mafra; João A. P. Coutinho. Using COSMO-RS in the Design of Deep Eutectic Solvents for the Extraction of Antioxidants from Rosemary. ACS Sustainable Chemistry & Engineering 2020, 8, 12132 -12141.
AMA StyleJosé Pedro Wojeicchowski, Ana M. Ferreira, Dinis O. Abranches, Marcos R. Mafra, João A. P. Coutinho. Using COSMO-RS in the Design of Deep Eutectic Solvents for the Extraction of Antioxidants from Rosemary. ACS Sustainable Chemistry & Engineering. 2020; 8 (32):12132-12141.
Chicago/Turabian StyleJosé Pedro Wojeicchowski; Ana M. Ferreira; Dinis O. Abranches; Marcos R. Mafra; João A. P. Coutinho. 2020. "Using COSMO-RS in the Design of Deep Eutectic Solvents for the Extraction of Antioxidants from Rosemary." ACS Sustainable Chemistry & Engineering 8, no. 32: 12132-12141.
Emanuelle L. P. De Faria; Ana M. Ferreira; Ana Filipa M. Cláudio; João A. P. Coutinho; Armando J. D. Silvestre; Mara G. Freire. Recovery of Syringic Acid from Industrial Food Waste with Aqueous Solutions of Ionic Liquids. ACS Sustainable Chemistry & Engineering 2019, 7, 14143 -14152.
AMA StyleEmanuelle L. P. De Faria, Ana M. Ferreira, Ana Filipa M. Cláudio, João A. P. Coutinho, Armando J. D. Silvestre, Mara G. Freire. Recovery of Syringic Acid from Industrial Food Waste with Aqueous Solutions of Ionic Liquids. ACS Sustainable Chemistry & Engineering. 2019; 7 (16):14143-14152.
Chicago/Turabian StyleEmanuelle L. P. De Faria; Ana M. Ferreira; Ana Filipa M. Cláudio; João A. P. Coutinho; Armando J. D. Silvestre; Mara G. Freire. 2019. "Recovery of Syringic Acid from Industrial Food Waste with Aqueous Solutions of Ionic Liquids." ACS Sustainable Chemistry & Engineering 7, no. 16: 14143-14152.
Aqueous biphasic systems (ABS) were applied in fast centrifugal partition chromatography (FCPC) for the purification of PEGylated cytochrome c conjugates.
João H. P. M. Santos; Ana M. Ferreira; Mafalda Almeida; Paula S. G. N. Quinteiro; Ana C. R. V. Dias; João A. P. Coutinho; Mara G. Freire; Carlota O. Rangel-Yagui; Sónia P. M. Ventura. Continuous separation of cytochrome-c PEGylated conjugates by fast centrifugal partition chromatography. Green Chemistry 2019, 21, 5501 -5506.
AMA StyleJoão H. P. M. Santos, Ana M. Ferreira, Mafalda Almeida, Paula S. G. N. Quinteiro, Ana C. R. V. Dias, João A. P. Coutinho, Mara G. Freire, Carlota O. Rangel-Yagui, Sónia P. M. Ventura. Continuous separation of cytochrome-c PEGylated conjugates by fast centrifugal partition chromatography. Green Chemistry. 2019; 21 (20):5501-5506.
Chicago/Turabian StyleJoão H. P. M. Santos; Ana M. Ferreira; Mafalda Almeida; Paula S. G. N. Quinteiro; Ana C. R. V. Dias; João A. P. Coutinho; Mara G. Freire; Carlota O. Rangel-Yagui; Sónia P. M. Ventura. 2019. "Continuous separation of cytochrome-c PEGylated conjugates by fast centrifugal partition chromatography." Green Chemistry 21, no. 20: 5501-5506.
Aqueous biphasic systems (ABS) formed by non-aromatic and non-fluorinated ionic liquids and carbohydrates are competitive separation platforms.
Maria V. Quental; Matheus M. Pereira; Ana M. Ferreira; Sónia N. Pedro; Shahla Shahriari; Aminou Mohamadou; João A. P. Coutinho; Mara G. Freire. Enhanced separation performance of aqueous biphasic systems formed by carbohydrates and tetraalkylphosphonium- or tetraalkylammonium-based ionic liquids. Green Chemistry 2018, 20, 2978 -2983.
AMA StyleMaria V. Quental, Matheus M. Pereira, Ana M. Ferreira, Sónia N. Pedro, Shahla Shahriari, Aminou Mohamadou, João A. P. Coutinho, Mara G. Freire. Enhanced separation performance of aqueous biphasic systems formed by carbohydrates and tetraalkylphosphonium- or tetraalkylammonium-based ionic liquids. Green Chemistry. 2018; 20 (13):2978-2983.
Chicago/Turabian StyleMaria V. Quental; Matheus M. Pereira; Ana M. Ferreira; Sónia N. Pedro; Shahla Shahriari; Aminou Mohamadou; João A. P. Coutinho; Mara G. Freire. 2018. "Enhanced separation performance of aqueous biphasic systems formed by carbohydrates and tetraalkylphosphonium- or tetraalkylammonium-based ionic liquids." Green Chemistry 20, no. 13: 2978-2983.
An integrated biocatalysis-separation process: the reaction step occurs in a homogeneous medium, followed by enzyme and product separation in a liquid–liquid system promoted by temperature changes.
Ana M. Ferreira; Helena Passos; Akiyoshi Okafuji; Ana P. M. Tavares; Hiroyuki Ohno; Mara G. Freire; João A. P. Coutinho. An integrated process for enzymatic catalysis allowing product recovery and enzyme reuse by applying thermoreversible aqueous biphasic systems. Green Chemistry 2018, 20, 1218 -1223.
AMA StyleAna M. Ferreira, Helena Passos, Akiyoshi Okafuji, Ana P. M. Tavares, Hiroyuki Ohno, Mara G. Freire, João A. P. Coutinho. An integrated process for enzymatic catalysis allowing product recovery and enzyme reuse by applying thermoreversible aqueous biphasic systems. Green Chemistry. 2018; 20 (6):1218-1223.
Chicago/Turabian StyleAna M. Ferreira; Helena Passos; Akiyoshi Okafuji; Ana P. M. Tavares; Hiroyuki Ohno; Mara G. Freire; João A. P. Coutinho. 2018. "An integrated process for enzymatic catalysis allowing product recovery and enzyme reuse by applying thermoreversible aqueous biphasic systems." Green Chemistry 20, no. 6: 1218-1223.
Chlorophylls and their derivatives are currently used in a wide range of applications. To replace the volatile organic solvents commonly applied for their extraction from biomass, aqueous solutions of nonionic surfactants are studied herein in the extraction of chlorophylls from spinach leaves. Aqueous solutions of a wide range of nonionic surfactants were investigated, allowing us to demonstrate the relevance of their hydrophilic–lipophilic balance (HLB) on the extraction performance and chlorophylls a/b selectivity, with the best results obtained with surfactants with a HLB ranging between 10 and 13. Furthermore, it was found a relevant impact of the surfactants aqueous solutions toward the biomass disruption, demonstrating that changes in the biomass structure allow a better access of the solvent to the target compounds embedded in the biopolymer matrix. A response surface methodology was then used to optimize operational conditions (surfactant concentration, solid–liquid ratio, and temperature), leading to a maximum extraction yield of chlorophylls of 0.94 mg/g. After the extraction step, the chlorophylls-rich extract was concentrated by heating above the surfactant–water cloud point, leading to a separation into two phases and to a concentration factor of 9 and a recovery of 97% of chlorophylls in the surfactant-rich phase. The antioxidant activity of the extracts was finally appraised, showing that the antioxidant activity of the aqueous chlorophylls-rich extracts is higher than that obtained with volatile organic solvents. The obtained results show the potential of aqueous solutions of nonionic surfactants to extract highly hydrophobic compounds from biomass and their potential for a direct use in cosmetic and nutraceutical applications, without requiring an additional recovery or purification step.
Ana Cláudia Leite; Ana M. Ferreira; Eduarda S. Morais; Imran Khan; Mara G. Freire; João A. P. Coutinho. Cloud Point Extraction of Chlorophylls from Spinach Leaves Using Aqueous Solutions of Nonionic Surfactants. ACS Sustainable Chemistry & Engineering 2017, 6, 590 -599.
AMA StyleAna Cláudia Leite, Ana M. Ferreira, Eduarda S. Morais, Imran Khan, Mara G. Freire, João A. P. Coutinho. Cloud Point Extraction of Chlorophylls from Spinach Leaves Using Aqueous Solutions of Nonionic Surfactants. ACS Sustainable Chemistry & Engineering. 2017; 6 (1):590-599.
Chicago/Turabian StyleAna Cláudia Leite; Ana M. Ferreira; Eduarda S. Morais; Imran Khan; Mara G. Freire; João A. P. Coutinho. 2017. "Cloud Point Extraction of Chlorophylls from Spinach Leaves Using Aqueous Solutions of Nonionic Surfactants." ACS Sustainable Chemistry & Engineering 6, no. 1: 590-599.
The design of the thermal behaviour – from an upper critical solution temperature (UCST) to a lower critical solution temperature (LCST) – of aqueous biphasic systems composed of water-soluble ammonium-based zwitterions.
Ana M. Ferreira; Helena Passos; Akiyoshi Okafuji; Mara G. Freire; João A. P. Coutinho; Hiroyuki Ohno. Designing the thermal behaviour of aqueous biphasic systems composed of ammonium-based zwitterions. Green Chemistry 2017, 19, 4012 -4016.
AMA StyleAna M. Ferreira, Helena Passos, Akiyoshi Okafuji, Mara G. Freire, João A. P. Coutinho, Hiroyuki Ohno. Designing the thermal behaviour of aqueous biphasic systems composed of ammonium-based zwitterions. Green Chemistry. 2017; 19 (17):4012-4016.
Chicago/Turabian StyleAna M. Ferreira; Helena Passos; Akiyoshi Okafuji; Mara G. Freire; João A. P. Coutinho; Hiroyuki Ohno. 2017. "Designing the thermal behaviour of aqueous biphasic systems composed of ammonium-based zwitterions." Green Chemistry 19, no. 17: 4012-4016.
Biocompatible aqueous solutions of ILs rich in 7-hydroxymatairesinol (HMR) can be safely used in cosmetic and nutraceutical applications.
Ana M. Ferreira; Eduarda S. Morais; Ana Cláudia Leite; Aminou Mohamadou; Bjarne Holmbom; Thomas Holmbom; Bruno M. Neves; João A. P. Coutinho; Mara G. Freire; Armando J. D. Silvestre. Enhanced extraction and biological activity of 7-hydroxymatairesinol obtained from Norway spruce knots using aqueous solutions of ionic liquids. Green Chemistry 2017, 19, 2626 -2635.
AMA StyleAna M. Ferreira, Eduarda S. Morais, Ana Cláudia Leite, Aminou Mohamadou, Bjarne Holmbom, Thomas Holmbom, Bruno M. Neves, João A. P. Coutinho, Mara G. Freire, Armando J. D. Silvestre. Enhanced extraction and biological activity of 7-hydroxymatairesinol obtained from Norway spruce knots using aqueous solutions of ionic liquids. Green Chemistry. 2017; 19 (11):2626-2635.
Chicago/Turabian StyleAna M. Ferreira; Eduarda S. Morais; Ana Cláudia Leite; Aminou Mohamadou; Bjarne Holmbom; Thomas Holmbom; Bruno M. Neves; João A. P. Coutinho; Mara G. Freire; Armando J. D. Silvestre. 2017. "Enhanced extraction and biological activity of 7-hydroxymatairesinol obtained from Norway spruce knots using aqueous solutions of ionic liquids." Green Chemistry 19, no. 11: 2626-2635.
Reversible production–separation systems can be prepared by varying the speciation of at least one of their components.
Ana M. Ferreira; Ana Filipa M. Cláudio; Mónica Válega; Fernando M. J. Domingues; Armando J. D. Silvestre; Robin D. Rogers; João A. P. Coutinho; Mara G. Freire. Switchable (pH-driven) aqueous biphasic systems formed by ionic liquids as integrated production–separation platforms. Green Chemistry 2017, 19, 2768 -2773.
AMA StyleAna M. Ferreira, Ana Filipa M. Cláudio, Mónica Válega, Fernando M. J. Domingues, Armando J. D. Silvestre, Robin D. Rogers, João A. P. Coutinho, Mara G. Freire. Switchable (pH-driven) aqueous biphasic systems formed by ionic liquids as integrated production–separation platforms. Green Chemistry. 2017; 19 (12):2768-2773.
Chicago/Turabian StyleAna M. Ferreira; Ana Filipa M. Cláudio; Mónica Válega; Fernando M. J. Domingues; Armando J. D. Silvestre; Robin D. Rogers; João A. P. Coutinho; Mara G. Freire. 2017. "Switchable (pH-driven) aqueous biphasic systems formed by ionic liquids as integrated production–separation platforms." Green Chemistry 19, no. 12: 2768-2773.
Immunoglobulins G (IgG) could become widespread biopharmaceuticals if cost-efficient processes for their extraction and purification are available. In this work, aqueous biphasic systems (ABS) composed of polyethylene glycols and a buffered salt, and with ionic liquids (ILs) as adjuvants, have been studied as alternative extraction and purification platforms of IgG from a rabbit serum source. Eleven ILs were investigated to provide insights on the chemical features which maximize the IgG partitioning. It is shown that in polymer-salt systems pure IgG preferentially partitions to the polymer-rich phase; yet, the complete extraction was never attained. Remarkably, after the addition of 5 wt% of adequate ILs to polymer-salt ABS, the complete extraction of pure IgG in a single-step was accomplished. The best systems and conditions were then applied to the extraction and purification of IgG directly from rabbit serum samples. The complete extraction of IgG in a single-step was maintained while its purity in the polymer-rich phase was enhanced by ca. 37% as compared to the IL-free ABS. The antibody stability was also evaluated revealing that appropriate ILs are able to maintain the IgG stability and can be used as phase-forming components of ABS when envisaging the purification of high-cost biopharmaceuticals.
Ana M. Ferreira; Vânia F.M. Faustino; Dibyendu Mondal; Joao Coutinho; Mara G. Freire. Improving the extraction and purification of immunoglobulin G by the use of ionic liquids as adjuvants in aqueous biphasic systems. Journal of Biotechnology 2016, 236, 166 -175.
AMA StyleAna M. Ferreira, Vânia F.M. Faustino, Dibyendu Mondal, Joao Coutinho, Mara G. Freire. Improving the extraction and purification of immunoglobulin G by the use of ionic liquids as adjuvants in aqueous biphasic systems. Journal of Biotechnology. 2016; 236 ():166-175.
Chicago/Turabian StyleAna M. Ferreira; Vânia F.M. Faustino; Dibyendu Mondal; Joao Coutinho; Mara G. Freire. 2016. "Improving the extraction and purification of immunoglobulin G by the use of ionic liquids as adjuvants in aqueous biphasic systems." Journal of Biotechnology 236, no. : 166-175.
Deep eutectic solvents (DES) have emerged in the past few years as a new class of solvents with promising applications in several fields. In the present work, the application of DES (formed by binary mixtures of cholinium chloride and carboxylic acids or urea) as phase-forming components of aqueous biphasic systems (ABS) is investigated. The mechanisms associated with the phases demixing of ABS composed of DES, as well as the DES stability in aqueous solutions, are investigated to address the critical question whether DES-based ABS are in fact ternary or quaternary mixtures. It is shown that the DES integrity is destroyed in ABS by the disruption of the hydrogen-bonding interactions of the complex (a result of the isolated components preferential solvation by water), and as confirmed by a nonstoichiometric partition of the DES components between the coexisting phases. As a result, there are no “real” DES-based ABS; instead, there is the formation of ABS composed of four components, where the carboxylic acid used as the hydrogen-bond donor species seems to act as an additive. Finally, it is shown that these ABS have an outstanding potential to be used in extraction processes, as it is here demonstrated with the complete separation of two dyes. However, the volatile nature of short chain carboxylic acids and the nonstoichiometric partition of the DES components in ABS make the development of recovery and recycling steps more difficult to accomplish.
Helena Passos; Daniel J. P. Tavares; Ana M. Ferreira; Mara G. Freire; João A. P. Coutinho. Are Aqueous Biphasic Systems Composed of Deep Eutectic Solvents Ternary or Quaternary Systems? ACS Sustainable Chemistry & Engineering 2016, 4, 2881 -2886.
AMA StyleHelena Passos, Daniel J. P. Tavares, Ana M. Ferreira, Mara G. Freire, João A. P. Coutinho. Are Aqueous Biphasic Systems Composed of Deep Eutectic Solvents Ternary or Quaternary Systems? ACS Sustainable Chemistry & Engineering. 2016; 4 (5):2881-2886.
Chicago/Turabian StyleHelena Passos; Daniel J. P. Tavares; Ana M. Ferreira; Mara G. Freire; João A. P. Coutinho. 2016. "Are Aqueous Biphasic Systems Composed of Deep Eutectic Solvents Ternary or Quaternary Systems?" ACS Sustainable Chemistry & Engineering 4, no. 5: 2881-2886.
Aqueous biphasic systems formed by fluorinated ionic liquids and carbohydrates are more amenable to be tunned.
Ana M. Ferreira; Pedro D. O. Esteves; Isabel Boal-Palheiros; Ana B. Pereiro; Luis Paulo Rebelo; Mara G. Freire. Enhanced tunability afforded by aqueous biphasic systems formed by fluorinated ionic liquids and carbohydrates. Green Chemistry 2015, 18, 1070 -1079.
AMA StyleAna M. Ferreira, Pedro D. O. Esteves, Isabel Boal-Palheiros, Ana B. Pereiro, Luis Paulo Rebelo, Mara G. Freire. Enhanced tunability afforded by aqueous biphasic systems formed by fluorinated ionic liquids and carbohydrates. Green Chemistry. 2015; 18 (4):1070-1079.
Chicago/Turabian StyleAna M. Ferreira; Pedro D. O. Esteves; Isabel Boal-Palheiros; Ana B. Pereiro; Luis Paulo Rebelo; Mara G. Freire. 2015. "Enhanced tunability afforded by aqueous biphasic systems formed by fluorinated ionic liquids and carbohydrates." Green Chemistry 18, no. 4: 1070-1079.
The textiles manufacturing is one of the core industries which discharges a heavy load of chemicals during the dying process. As a result, the release of large contents of dyes through aqueous effluents leads to both environmental and economic concerns. Aiming at developing more benign methodologies than those studied hitherto, this work proposes a novel approach to remove dyes from aqueous discharges by the use of ionic liquid (IL)-based aqueous two-phase systems (ATPS). A detailed study on the partition coefficients and extraction efficiencies of a set of textile dyes (chloranilic acid, indigo blue and sudan III) using ATPS composed of ILs (phosphonium- and imidazolium-based) and an inorganic (aluminium sulphate) or organic salt (potassium citrate) is here addressed. The gathered data allow the evaluation of the IL chemical structure, the nature of the salt, as well as the pH of the aqueous medium. The results obtained reveal that a proper selection of the IL and salt can lead to the complete extraction of the three dyes to the IL-rich phase in a single-step procedure. Moreover, the dyes recovery to further allow the reuse of the IL-rich phase is also described. This new approach, using hydrophilic ILs, is consequently more environmentally friendly and could be envisaged as a promising process for reducing the pollution of wastewaters. (C) 2014 Elsevier B.V. All rights reserved
Ana M. Ferreira; Joao Coutinho; Ana Maria Fernandes; Mara Freire. Complete removal of textile dyes from aqueous media using ionic-liquid-based aqueous two-phase systems. Separation and Purification Technology 2014, 128, 58 -66.
AMA StyleAna M. Ferreira, Joao Coutinho, Ana Maria Fernandes, Mara Freire. Complete removal of textile dyes from aqueous media using ionic-liquid-based aqueous two-phase systems. Separation and Purification Technology. 2014; 128 ():58-66.
Chicago/Turabian StyleAna M. Ferreira; Joao Coutinho; Ana Maria Fernandes; Mara Freire. 2014. "Complete removal of textile dyes from aqueous media using ionic-liquid-based aqueous two-phase systems." Separation and Purification Technology 128, no. : 58-66.
The extraction of caffeine from bioresources using more benign and cost-effective processes is of fundamental relevance towards the finding of alternative (bio)pesticides. Classically, the best attempts to extract caffeine from biomass have resulted in low efficiency and in a large consumption of hazardous organic solvents and/or energy requirements. Here, we report an enhanced and selective extraction of caffeine from guaraná (Paullinia cupana, Sapindaceae) seeds using aqueous solutions of ionic liquids. Several ionic liquids composed of imidazolium or pyrrolidinium cations combined with the chloride, acetate and tosylate anions were investigated. Furthermore, the effect of the cation alkyl side chain length and the presence of functionalized groups were also addressed. Additional conditions such as the ionic liquid concentration, the contact time, the solid–liquid ratio and temperature were further optimized by a response surface methodology. Outstanding extraction yields (up to 9 wt% of caffeine per guaraná dry weight) were obtained at a moderate temperature and in a short-time. The recyclability and reusability of the ionic liquids were also confirmed. For the first time it is shown that aqueous solutions of ionic liquids are superior alternatives for the solid–liquid extraction of caffeine from biomass samples and, as a result, the development of an ionic-liquid-based process is straightforwardly envisaged.
Ana Filipa Cláudio; Ana M. Ferreira; Mara Freire; Joao Coutinho. Enhanced extraction of caffeine from guaraná seeds using aqueous solutions of ionic liquids. Green Chemistry 2013, 15, 2002 -2010.
AMA StyleAna Filipa Cláudio, Ana M. Ferreira, Mara Freire, Joao Coutinho. Enhanced extraction of caffeine from guaraná seeds using aqueous solutions of ionic liquids. Green Chemistry. 2013; 15 (7):2002-2010.
Chicago/Turabian StyleAna Filipa Cláudio; Ana M. Ferreira; Mara Freire; Joao Coutinho. 2013. "Enhanced extraction of caffeine from guaraná seeds using aqueous solutions of ionic liquids." Green Chemistry 15, no. 7: 2002-2010.