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1.
Heliyon ; 10(4): e25782, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38375314

RESUMEN

Digital Twin (DT) consists of a recent technology that can enable sustainability. However, Digital Twins are still in early stages of adoption, especially in households, and so the determinants to this adoption have not yet been determined. The aim of this study is to fill this research gap through providing a conceptual model of the drivers to the adoption of Digital Twins in households and it's relation to well-being. This study is developed as a mixed-methods research. The model is produced qualitatively, based on literature discoveries and key findings from interviews with experts and possible consumers. Afterwards, the model was validated with data collected through a questionnaire with 149 respondents. Results show that a set of informational, social, environmental and utility factors can influence the intention to adopt Digital Twins as a sustainable energy solution, and consequently the perceived well-being.

2.
Biotechnol Prog ; : e3427, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38289674

RESUMEN

Process intensification efforts have renewed interest in the potential of end-to-end continuous manufacture with column-free capture alternatives. This article describes a decisional tool that encompasses mass balance and design equations, process economics, stochastic simulation and multi-criteria decision-making and enables the evaluation of different batch, and continuous flowsheets for monoclonal antibody (mAb) manufacture. The traditional batch process was compared with end-to-end continuous bioprocesses with either protein A capture or column-free capture employing aqueous two-phase extraction or precipitation from economic, environmental, and robustness perspectives. The cost of goods analysis predicted that continuous flowsheets could offer substantial cost savings (~20%-40%) over the batch process at low and medium annual commercial demands (100-500 kg); however, at tonnage demands they resulted in either comparable or higher costs. Comparing the continuous options, the continuous flowsheets with protein A or precipitation yielded similar COG/g values, while aqueous two-phase extraction presented higher costs. The analysis of overall process mass intensities accounting for water and consumables suggested that the continuous flowsheet with protein A would result in the lowest environmental burden. When the economic, environmental, and operational criteria were reconciled using multi-criteria decision-making analysis, the continuous protein A-based flowsheet was found to be the most favorable. A target analysis highlighted the need for process improvements in the following parameters to reduce the manufacturing costs of the continuous column-free capture options below that of protein A: the perfusion volumetric productivity, the harvested cell culture fluid percentage in column-free operations, the column-free step yields along with the implementation of buffer concentrates.

3.
Hortic Res ; 10(12): uhad220, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38077496

RESUMEN

The plant-specific family of GRAS transcription factors has been wide implicated in the regulation of transcriptional reprogramming associated with a diversity of biological functions ranging from plant development processes to stress responses. Functional analyses of GRAS transcription factors supported by in silico structural and comparative analyses are emerging and clarifying the regulatory networks associated with their biological roles. In this review, a detailed analysis of GRAS proteins' structure and biochemical features as revealed by recent discoveries indicated how these characteristics may impact subcellular location, molecular mechanisms, and function. Nomenclature issues associated with GRAS classification into different subfamilies in diverse plant species even in the presence of robust genomic resources are discussed, in particular how it affects assumptions of biological function. Insights into the mechanisms driving evolution of this gene family and how genetic and epigenetic regulation of GRAS contributes to subfunctionalization are provided. Finally, this review debates challenges and future perspectives on the application of this complex but promising gene family for crop improvement to cope with challenges of environmental transition.

4.
Artículo en Inglés | LILACS | ID: biblio-1538288

RESUMEN

In patients with Chronic Rheumatic Carditis, active carditis is an often underdiagnosed condition. Rheumatic attacks promote the aggravation of existing lesions, leading to a deterioration of the patient's clinical condition. Thus, reducing the morbidity and mortality of the disease depends, in part, on controlling relapses through secondary prophylaxis. Underdiagnosis is due in part to the occurrence of subclinical rheumatic attacks. This study was carried out with data from patients who were diagnosed with Chronic Rheumatic Carditis and who underwent cardiac surgery for valve replacement or repair, without clinical or laboratory evidence of rheumatic outbreak. A fragment of myocardium was sent for histopathological analysis. Data on the frequency of histopathological alterations compatible with a rheumatic outbreak were analyzed. After analysis, 80% of patients showed changes compatible with inflammatory activity. Of these, 87.5% had lymphocytic infiltrate; 25% had Aschoff's nodules. The most frequent histopathological findings of chronic disease were myocardial hypertrophy in 56.7% of patients and fibrosis in 53.3% (AU).


Nos pacientes com Cardite Reumática Crônica, a cardite em atividade é uma condição frequentemente subdiagnos-ticada. Os surtos reumáticos promovem o agravamento das lesões já existentes, levando a uma deterioração da condição clínica do paciente. Dessa forma a redução da morbimortalidade da doença depende, em parte, do contro-le de recidivas a partir da profilaxia secundária. O subdiagnóstico deve-se em parte a ocorrência de surtos reumáti-cos subclínicos. Este estudo foi realizado com dados dos pacientes que tiveram o diagnóstico de Cardite Reumática Crônica e foram submetidos à cirurgia cardíaca para troca ou plastia valvar, sem evidência clínica ou laboratorial de surto reumático. Um fragmento de miocárdio foi enviado para análise histopatológica. Foram analisados os dados de frequência de alterações histopatológicas compatíveis com surto reumático. Após análises, 80% dos pacientes apresentaram alterações compatíveis com atividade inflamatória. Desses, 87,5% apresentavam infiltrado linfocitá-rio; 25% apresentavam nódulos de Aschoff. Os achados histopatológicos de doença crônica mais frequentes foram hipertrofia miocárdica em 56,7% pacientes e fibrose em 53,3% (AU).


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Adolescente , Adulto , Fiebre Reumática , Miocarditis
5.
BMJ Case Rep ; 16(9)2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37723096

RESUMEN

An adolescent was referred to the emergency department due to abnormal uterine haemorrhages in the previous 2 months, associated with dizziness in the last month. At observation, she was haemodynamically stable, with good clinical impression, but evident mucocutaneous pallor. Full blood count confirmed a severe anaemia (haemoglobin 47 g/L). She received red blood cell transfusion (10 mL/kg) and started oral oestradiol. She was discharged, with oral oestradiol and oral iron supplementation. Two weeks later, she started treatment with oestradiol and progestin. The patient had a good recovery, without new similar episodes.


Asunto(s)
Estradiol , Hemorragia Uterina , Adolescente , Femenino , Humanos , Hemorragia Uterina/etiología , Mareo , Servicio de Urgencia en Hospital , Transfusión de Eritrocitos
6.
Transplant Proc ; 55(7): 1555-1560, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37419736

RESUMEN

BACKGROUND: Kidney transplantation is ideal for children and adolescents with chronic end-stage renal disease because it offers better growth, development, and quality of life. Donor choice is vitally important in this age group, given the long life expectancy of these patients. METHODS: A retrospective analysis of pediatric patients (<18 years) who underwent kidney transplantation from January 1999 to December/2018 was performed. Short- and long-term outcomes were compared between living and deceased donor transplants. RESULTS: We included 59 pediatric kidney transplant recipients, 12 from a living donor and 47 from a deceased donor. Thirty-six (61.0%) patients were boys, and 5 (8.5%) had a retransplant. There were no differences between groups on sex, race, and weight of the recipient and donor, as well as the age and the etiology of the recipient's primary disease. Most recipients received induction immunosuppression with basiliximab and maintenance with triple therapy, with no differences between groups. Living donor transplants were mostly pre-emptive (58.3% vs 4.3%, P < .001) and had fewer HLA mismatches (≤3: 90.9% vs 13.0%, P < .001), older donors (38.4 vs 24.3 years, P < .001) and shorter hospital stays (8.8 vs 14.1 days, P = .004). There were no statistically significant differences regarding medical-surgical complications and graft or patient survival. However, we found that at 13 years post-transplant 91.7% of the living donor grafts were functioning vs 72.3% of the deceased donor grafts. CONCLUSION: Our experience points out that a living donor graft in pediatric patients is associated with a higher probability of pre-emptive transplant, shorter hospital stay, greater HLA compatibility, and increased graft survival.


Asunto(s)
Trasplante de Riñón , Masculino , Adolescente , Humanos , Niño , Femenino , Trasplante de Riñón/efectos adversos , Estudios Retrospectivos , Calidad de Vida , Resultado del Tratamiento , Donantes de Tejidos , Donadores Vivos , Supervivencia de Injerto
8.
Hortic Res ; 9: uhac217, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36479580

RESUMEN

Botrytis cinerea is responsible for the gray mold disease, severely affecting Vitis vinifera grapevine and hundreds of other economically important crops. However, many mechanisms of this fruit-pathogen interaction remain unknown. The combined analysis of the transcriptome and metabolome of green fruits infected with B. cinerea from susceptible and tolerant genotypes was never performed in any fleshy fruit, mostly because green fruits are widely accepted to be resistant to this fungus. In this work, peppercorn-sized fruits were infected in the field or mock-treated, and berries were collected at green (EL32) stage from a susceptible (Trincadeira) and a tolerant (Syrah) variety. RNAseq and GC-MS data suggested that Syrah exhibited a pre-activated/basal defense relying on specific signaling pathways, hormonal regulation, namely jasmonate and ethylene metabolisms, and linked to phenylpropanoid metabolism. In addition, putative defensive metabolites such as shikimic, ursolic/ oleanolic, and trans-4-hydroxy cinnamic acids, and epigallocatechin were more abundant in Syrah than Trincadeira before infection. On the other hand, Trincadeira underwent relevant metabolic reprogramming upon infection but was unable to contain disease progression. RNA-seq analysis of the fungus in planta revealed an opposite scenario with higher gene expression activity within B. cinerea during infection of the tolerant cultivar and less activity in infected Trincadeira berries. The results suggested an activated virulence state during interaction with the tolerant cultivar without visible disease symptoms. Together, this study brings novel insights related to early infection strategies of B. cinerea and the green berry defense against necrotrophic fungi.

9.
Molecules ; 27(21)2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36364294

RESUMEN

Detergent formulations for cleaning a carbonized soil­degreasers­typically comprise surfactants, organic solvents, phosphate-based cleaning agents, and alkaline agents, which results in high pH values (>11) that raise human and environmental risks. It is important to develop eco-friendly and safer degreasers, while maintaining their cleaning efficiency. In this work, simple degreaser formulations, with a pH below 11 and without phosphates, were developed by using a mixture of solvent, surfactant, and water to remove carbonized soil. The efficiency of the new degreaser formulations (with 5 wt% solvent, 5 wt% nonionic or ionic surfactant, and 90 wt% water) was evaluated by an abrasion test in the removal of carbonized soil from ceramic and stainless steel surfaces and compared with a commercial product. The results obtained show that the formulations comprising isopropylene glycol (IPG) with C11−C13 9EOs and diethylene glycol butyl ether (BDG) with octyltrimethylammonium octanoate ([N1118][C8O2]) present the best cleaning efficiency for both surfaces. The composition of these formulations was optimized for each surface using a mixture design. The resulting formulations, despite having a simpler composition, a pH lower than 11, and being phosphate-free, presented a cleaning efficiency equal or slightly higher than the commercial control. These results show that it is possible to design degreasers that are much less aggressive to the environment and user, while simultaneously fulfilling the market requirements.


Asunto(s)
Detergentes , Suelo , Humanos , Tensoactivos/química , Agua , Solventes
10.
Adv Mater ; 34(31): e2200352, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35695028

RESUMEN

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 stability conferred by emulsion systems, namely mild aqueous two-phase systems (ATPS), or non-equilibrated analogues. However, the application of non-spherical structures has mostly been reported while keeping the fabricated materials at a stable interface, limiting the free-standing character, mobility and transposition of the obtained structures to different setups. Here, the fabrication of self-standing, malleable and perfusable tubular systems through all-aqueous interfacial assembly is shown, culminating in the preparation of independent objects with stability and homogeneity after disruption of the polymer-based aqueous separating system. Those hollow structures can be fabricated with a variety of widths, and rapidly printed as long structures at flow rates of 15 mm s-1 . The materials are used as compartments for cell culture, showcasing high cytocompatibility, and can be tailored to promote cell adhesion. Such structures may find application in fields that benefit from freeform tubular structures, including the biomedical field with, for example, cell encapsulation, and benchtop preparation of microfluidic devices.


Asunto(s)
Dispositivos Laboratorio en un Chip , Agua , Polímeros , Agua/química
11.
Adv Healthc Mater ; 10(10): e2100266, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33764007

RESUMEN

The therapeutic effectiveness and biological relevance of technologies based on adherent cells depend on platforms that enable long-term culture in controlled environments. Liquid-core capsules have been suggested as semipermeable moieties with spatial homogeneity due to the high mobility of all components in their core. The lack of cell-adhesive sites in liquid-core structures often hampers their use as platforms for stem cell-based technologies for long-term survival and cell-directed self-organization. Here, the one-step fast formation of robust polymeric capsules formed by interfacial complexation of oppositely charged polyelectrolytes in an all-aqueous environment, compatible with the simultaneous encapsulation of mesenchymal stem/stromal cells (MSCs) and microcarriers, is described. The adhesion of umbilical cord MSCs to polymeric microcarriers enables their aggregation and culture for more than 21 days in capsules prepared either manually by dropwise addition, or by scalable electrohydrodynamic atomization, generating robust and stable capsules. Cell aggregation and secretion overtime can be tailored by providing cells with static or dynamic (bioreactor) environments.


Asunto(s)
Células Madre Mesenquimatosas , Cápsulas , Polielectrolitos , Células Madre , Cordón Umbilical
12.
Eur J Clin Microbiol Infect Dis ; 39(9): 1745-1752, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32367215

RESUMEN

Despite constituting part of the human commensal flora, Corynebacterium pseudodiphtheriticum has been recognized as a potentially infectious agent, most frequently in immunocompromised patients or individuals with other morbidity factors, but significant association to comorbid states remains unproven. This study's purpose was to assess clinical significance, risk factors for infection and antimicrobial susceptibility of C. pseudodiphtheriticum isolates. A retrospective observational study was conducted. Relevance of isolation was determined by clinical, laboratory, and imaging criteria. Forty-nine isolates occurred in 47 episodes. Colonization was assumed in 12% and infection in 78%, of which 51% were nosocomial. Patients with infection were older, with male predominance; both age and gender were statistically significant (p < 0.05) between infection and colonization groups. Although dyslipidemia (58%), arterial hypertension (58%), invasive procedures (56%), and chronic lung disease (50%) were prevalent in the infection group, no comorbidity was a significant risk factor for infection compared with colonization. Charlson comorbidity index showed no statistically difference between groups. Mortality rate was 14% in infection. Respiratory samples were the main isolation product; all tested strains were susceptible to amoxicillin/clavulanate and vancomycin. Resistant strains were observed for clindamycin (77%) and erythromycin (48%). C. pseudodiphtheriticum isolation was associated with infection in most cases. Despite the high prevalence of comorbidities and invasive procedures, no factors other than age and gender were significantly associated with infection. Although C. pseudodiphtheriticum may constitute a contaminant or colonizer in clinical samples, positive cultures in patients with signs and symptoms consistent with infection should not be neglected.


Asunto(s)
Infecciones por Corynebacterium/epidemiología , Corynebacterium/patogenicidad , Infecciones del Sistema Respiratorio/epidemiología , Factores de Edad , Anciano , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Corynebacterium/efectos de los fármacos , Infecciones por Corynebacterium/tratamiento farmacológico , Infecciones por Corynebacterium/microbiología , Farmacorresistencia Microbiana , Femenino , Hospitales Universitarios , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Portugal/epidemiología , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/microbiología , Estudios Retrospectivos , Factores Sexuales
13.
Food Funct ; 10(11): 7216-7226, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31612177

RESUMEN

Offspring of dams exposed to excess folic acid during the perigestational period have been shown by us to be predisposed to metabolic dysfunction revealed by hyperglycemia, glucose intolerance, increased insulin and decreased adiponectin in late adulthood. This work aims to characterize adipocyte phenotype and expression profile of genes in the regulation of lipid and glucose metabolism in visceral adipose tissue and in skeletal muscle. From mating until weaning, a recommended dose of folic acid for pregnancy (C, 2 mg of folic acid per kg of diet) or a high folic acid dose (HFA, 40 mg of folic acid per kg of diet) was administered to Sprague-Dawley females. At 10 months of age progeny were divided into groups fed the standard chow (C/STD and HFA/STD) and groups fed the standard chow plus drinking water with 10% fructose (C/FRU and HFA/FRU), as an additional metabolic challenge. Adipocyte morphology and quantification of key genes involved in lipid and glucose metabolism were studied in visceral adipose tissue and skeletal muscle of 13 months old offspring. HFA exposure led to an enlargement of visceral adipose cells most likely mediated by an upregulation of lipoprotein lipase, and it tended to downregulate Glut4 in visceral adipose tissue and skeletal muscle. Fructose exposure in a background of perigestational excess folic acid, but not in controls, induced an upregulation of lipogenesis pathway genes and it decreased jejunal expression of the proton-coupled folate transporter (Pcft1). In addition, fructose exposure led to a downregulation of jejunal Sglt1 in control animals. Our data suggest that high folic acid exposure during the perigestational period caused morphologic and genic alterations related to insulin resistant states indicating that this intervention may act as an effective programmer of long-term metabolic dysfunction.


Asunto(s)
Suplementos Dietéticos/efectos adversos , Ácido Fólico/efectos adversos , Enfermedades Metabólicas/etiología , Efectos Tardíos de la Exposición Prenatal/etiología , Animales , Suplementos Dietéticos/análisis , Femenino , Ácido Fólico/administración & dosificación , Transportador de Glucosa de Tipo 4/genética , Transportador de Glucosa de Tipo 4/metabolismo , Resistencia a la Insulina , Grasa Intraabdominal/metabolismo , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Enfermedades Metabólicas/genética , Enfermedades Metabólicas/metabolismo , Músculo Esquelético/metabolismo , Embarazo , Efectos Tardíos de la Exposición Prenatal/genética , Efectos Tardíos de la Exposición Prenatal/metabolismo , Transportador de Folato Acoplado a Protón/genética , Transportador de Folato Acoplado a Protón/metabolismo , Ratas , Ratas Sprague-Dawley
14.
J Solution Chem ; 48(7): 983-991, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31409937

RESUMEN

The order of the salting-in or salting-out inducing ability of ions on the aqueous solubility of macromolecules in aqueous solutions is known as the Hofmeister series. Taking into account that ionic liquids (ILs) are constituted by ions, they can exert similar effects on the solubility of other ILs in aqueous media. In order to expand the knowledge on the salting-in/-out ability of ILs, experimental studies on the solubility of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonylimide) in water in presence of other IL/salts were conducted at 298.15 K at atmospheric pressure. Both the impact of the anion and cation of the IL were evaluated with the following ILs/salts: 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium hydrogensulfate, cholinium bis(trifluoromethylsulfonyl)imide, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and lithium bis(trifluoromethylsulfonyl)imide, in a wide composition range. As happens with common salts, both salting-in and salting-out effects exerted by ILs were observed, with a higher impact exerted by the IL anion on the salting-out phenomenon. These data allow to better understand the ILs impact when designing liquid-liquid separation processes.

15.
Front Chem ; 7: 459, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31316969

RESUMEN

The food industry produces significant amounts of waste, many of them rich in valuable compounds that could be recovered and reused in the framework of circular economy. The development of sustainable and cost-effective technologies to recover these value added compounds will contribute to a significant decrease of the environmental footprint and economic burden of this industry sector. Accordingly, in this work, aqueous biphasic systems (ABS) composed of cholinium-derived bistriflimide ionic liquids (ILs) and carbohydrates were investigated as an alternative process to simultaneously separate and recover antioxidants and carbohydrates from food waste. Aiming at improving the biocompatible character of the studied ILs and proposed process, cholinium-derived bistriflimide ILs were chosen, which were properly designed by playing with the cation alkyl side chain and the number of functional groups attached to the cation to be able to create ABS with carbohydrates. These ILs were characterized by cytotoxicity assays toward human intestinal epithelial cells (Caco-2 cell line), demonstrating to have a significantly lower toxicity than other well-known and commonly used fluorinated ILs. The capability of these ILs to form ABS with a series of carbohydrates, namely monosaccharides, disaccharides and polyols, was then appraised by the determination of the respective ternary liquid-liquid phase diagrams at 25°C. The studied ABS were finally used to separate carbohydrates and antioxidants from real food waste samples, using an expired vanilla pudding as an example. With the studied systems, the separation of the two products occurs in one-step, where carbohydrates are enriched in the carbohydrate-rich phase and antioxidants are mainly present in the IL-rich phase. Extraction efficiencies of carbohydrates ranging between 89 and 92% to the carbohydrate-rich phase, and antioxidant relative activities ranging between 65 and 75% in the IL-rich phase were obtained. Furthermore, antioxidants from the IL-rich phase were recovered by solid-phase extraction, and the IL was recycled for two more times with no losses on the ABS separation performance. Overall, the obtained results show that the investigated ABS are promising platforms to simultaneously separate carbohydrates and antioxidants from real food waste samples, and could be used in further related applications foreseeing industrial food waste valorization.

16.
Biochem Eng J ; 141: 239-246, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30944543

RESUMEN

Ionic liquids (ILs) as adjuvants in polymer-salt aqueous two-phase systems (ATPS) have been used to improve the extraction of biomolecules. However, the impact of ILs as adjuvants on the partition of biomolecules is still poorly understood. Previous works mostly focused on ATPS based on strong salting-out agents, which may mask the IL effect. In this work, ATPS formed by polyethylene glycol (PEG 400) and a weak salting-out salt ((NH4)2SO4) with a wide number of ILs as adjuvants (chloride-based combined with cholinium, imidazolium, pyrrolidinium, piperidinium, tetralkylammonium and tetralkylphosphonium cations) were investigated. The respective phase diagrams were determined, and the systems extraction performance for a wide range of biomolecules (phenolic compounds, alkaloids and amino acids) was investigated. The results obtained show that ILs as adjuvants in polymer-salt ATPS modulate the partition of biomolecules. In particular, more hydrophobic ILs significantly enhance the partition of more hydrophobic biomolecules to the PEG-rich phase (where the IL is enriched). Furthermore, the intensity of the IL effect is more pronounced when using weak salting-out agents. A linear correlation between the biomolecules and the ILs partition coefficients, and with the biomolecules octanol-water partition coefficients, was found. In most ATPS formed by polymers and salts using ILs as adjuvants, the biomolecules partition is driven by the ILs partition and by the difference in hydrophobicity between the coexisting phases.

17.
J Chem Technol Biotechnol ; 93(7): 1931-1939, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30270961

RESUMEN

BACKGROUND: The use of antibodies, such as immunoglobulin G (IgG), has faced a significant growth in the past decades for biomedical and research purposes. However, antibodies are high cost biopharmaceuticals, for which the development of alternative and cost-effective purification strategies is still in high demand. RESULTS: Aqueous biphasic systems (ABS) composed of poly(propylene glycol) (PPG) and cholinium-based ionic liquids (ILs) were investigated for the separation of IgG. The ABS phase diagrams were determined and characterized whenever required. Initial optimization studies with commercial IgG were carried out, followed by the extraction of IgG from rabbit serum. In all ABS, IgG preferentially partitions to the IL-rich phase, unveiling preferential interactions between IgG and ILs. Good results were obtained with commercial IgG, with extraction efficiencies ranging between 93% and 100%, and recovery yields ranging between 20% and 100%. Two of the best and two of the worst identified ABS were then evaluated in what concerns their performance to separate and recover IgG from rabbit serum. With these ABS, extraction efficiencies of 100% and recovery yields > 80% were obtained, indicating an increase in the recovery yield and extraction efficiencies when using real matrices. Under the best conditions studied, IgG with a purity level of 49% was obtained in a single-step. This purity level of IgG is higher than those previously reported using other IL-polymer ABS. CONCLUSION: IgG preferentially migrates to the IL-rich phase in ABS formed by ILs and polymers, allowing the design of effective separation systems for its recovery from serum samples.

18.
Adv Sci (Weinh) ; 5(10): 1800576, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30356931

RESUMEN

Aqueous biphasic systems (ABS) formed by water, ionic liquids (ILs), and salts, in which the two phases are water rich, are demonstrated here to act as potential membrane-free batteries. This concept is feasible due to the selective enrichment of redox organic molecules in each aqueous phase of ABS, which spontaneously form two liquid-phases above given concentrations of salt and IL. Therefore, the required separation of electrolytes in the battery is not driven by an expensive membrane that hampers mass transfer, but instead, by the intrinsic immiscibility of the two liquid phases. Moreover, the crosscontamination typically occurring through the ineffective membranes is determined by the partition coefficients of the active molecules between the two phases. The phase diagrams of a series of IL-based ABS are characterized, the partition coefficients of several redox organic molecules are determined, and the electrochemistry of these redox-active immiscible phases is evaluated, allowing appraisal of the battery performance. Several redox ABS that may be used in total aqueous membrane-free batteries with theoretical battery voltages as high as 1.6 V are identified. The viability of a membrane-free battery composed of an IL-based ABS containing methyl viologen and 2,2,6,6-tetramethyl-1-piperidinyloxy as active species is demonstrated.

19.
J Chem Technol Biotechnol ; 93(7): 1940-1947, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30275632

RESUMEN

BACKGROUND: Levodopa is a precursor of several neurotransmitters, such as dopamine, and is used in the treatment of the Parkinson's disease. In this work, an alternative strategy was studied to separate levodopa from similar biomolecules using aqueous two-phase systems (ATPS). RESULTS: Ternary ATPS composed of polyethylene glycol (PEG) 400 or ionic liquids (ILs), citrate buffer (K3C6H5O7/C6H8O7) at pH 7.0 and water, and quaternary ATPS composed of PEG 400, K3C6H5O7/C6H8O7 at pH 7.0, water and the same ILs at 5 wt%, were studied. The respective liquid-liquid phase diagrams were determined at 298 K to appraise the mixture compositions required to form two-phase systems, followed by studies of the partition of levodopa and structurally similar biomolecules (dopamine, L-phenylalanine, and L-tyrosine). Their partition coefficients and extraction efficiencies have been determined, and the selectivity of the ATPS to separate levodopa from the remaining biomolecules evaluated. CONCLUSION: The results obtained indicated that PEG-based ATPS were the most effective to separate levodopa from L-phenylalanine while the separation from the other biomolecules was better using IL-based ATPS, in particular those based on [P4444]Cl and [N4444]Cl, with extraction efficiencies of levodopa to the salt-rich phase ranging between 62.7 and 74.0%, and of the remaining biomolecules to polymer/IL-rich phase up to 91.5%.

20.
Chem Commun (Camb) ; 54(58): 8104-8107, 2018 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-29972155

RESUMEN

Sustainable hydrophobic eutectic solvents, composed of low-priced and biodegradable terpenes and fatty acids, were used for the extraction and separation of Cu(ii) from other transition metals in mildly acidic solutions. Multiple parameters were evaluated for metal extraction and the hydrophobic eutectic solvent was successfully recovered and reused.

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