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1.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38473998

RESUMO

Interferon alpha-2b (IFN-α2b) is an essential cytokine widely used in the treatment of chronic hepatitis C and hairy cell leukemia, and serum albumin is the most abundant plasma protein with numerous physiological functions. Effective single-step aqueous biphasic system (ABS) extraction for the simultaneous purification of IFN-α2b and BSA (serum albumin protein) was developed in this work. Effects of the ionic liquid (IL)-based ABS functionalization, fluorinated ILs (FILs; [C​2C​1Im][C​4F​9SO​3] and [N​1112(OH)][C​4F​9SO​3]) vs. mere fluoro-containing IL ([C​4C​1Im][CF​3SO​3]), in combination with sucrose or [N​1112(OH)][H​2PO​4] (well-known globular protein stabilizers), or high-charge-density salt K​3PO​4 were investigated. The effects of phase pH, phase water content (%wt), phase composition (%wt), and phase volume ratio were investigated. The phase pH was found to have a significant effect on IFN-α2b and BSA partition. Experimental results show that simultaneous single-step purification was achieved with a high yield (extraction efficiency up to 100%) for both proteins and a purification factor of IFN-α2b high in the enriched IFN-α2b phase (up to 23.22) and low in the BSA-enriched phase (down to 0.00). SDS-PAGE analysis confirmed the purity of both recovered proteins. The stability and structure of IFN-α2b and BSA were preserved or even improved (FIL-rich phase) during the purification step, as evaluated by CD spectroscopy and DSC. Binding studies of IFN-α2b and BSA with the ABS phase-forming components were assessed by MST, showing the strong interaction between FILs aggregates and both proteins. In view of their biocompatibility, customizable properties, and selectivity, FIL-based ABSs are suggested as an improved purification step that could facilitate the development of biologics.


Assuntos
Líquidos Iônicos , Albumina Sérica , Humanos , Albumina Sérica/química , Líquidos Iônicos/química , Interferon-alfa/farmacologia , Água/química , Proteínas Recombinantes
2.
Int J Mol Sci ; 25(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38891953

RESUMO

This work unfolds functionalized ABSs composed of FILs ([C2C1Im][C4F9SO3] and [N1112(OH)][C4F9SO3]), mere fluoro-containing ILs ([C2C1Im][CF3SO3] and [C4C1Im][CF3SO3]), known globular protein stabilizers (sucrose and [N1112(OH)][C4F9SO3]), low-molecular-weight carbohydrate (glucose), and even high-charge density salt (K3PO4). The ternary phase diagrams were determined, stressing that FILs highly increased the ability for ABS formation. The functionalized ABSs (FILs vs. mere fluoro-containing ILs) were used to extract lysozyme (Lys). The ABSs' biphasic regions were screened in terms of protein biocompatibility, analyzing the impact of ABS phase-forming components in Lys by UV-VIS spectrophotometry, CD spectroscopy, fluorescence spectroscopy, DSC, and enzyme assay. Lys partition behavior was characterized in terms of extraction efficiency (% EE). The structure, stability, and function of Lys were maintained or improved throughout the extraction step, as evaluated by CD spectroscopy, DSC, enzyme assay, and SDS-PAGE. Overall, FIL-based ABSs are more versatile and amenable to being tuned by the adequate choice of the phase-forming components and selecting the enriched phase. Binding studies between Lys and ABS phase-forming components were attained by MST, demonstrating the strong interaction between Lys and FILs aggregates. Two of the FIL-based ABSs (30 %wt [C2C1Im][C4F9SO3] + 2 %wt K3PO4 and 30 %wt [C2C1Im][C4F9SO3] + 25 %wt sucrose) allowed the simultaneous purification of Lys and BSA in a single ABS extraction step with high yield (extraction efficiency up to 100%) for both proteins. The purity of both recovered proteins was validated by SDS-PAGE analysis. Even with a high-charge density salt, the FIL-based ABSs developed in this work seem more amenable to be tuned. Lys and BSA were purified through selective partition to opposite phases in a single FIL-based ABS extraction step. FIL-based ABSs are proposed as an improved extraction step for proteins, based on their biocompatibility, customizable properties, and selectivity.


Assuntos
Líquidos Iônicos , Muramidase , Líquidos Iônicos/química , Muramidase/química , Muramidase/isolamento & purificação , Muramidase/metabolismo , Halogenação , Água/química , Proteínas/química , Proteínas/isolamento & purificação , Animais
3.
Environ Sci Technol ; 56(9): 5898-5909, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35435682

RESUMO

In recent years, the fight against climate change and the mitigation of the impact of fluorinated gases (F-gases) on the atmosphere is a global concern. Development of technologies that help to efficiently separate and recycle hydrofluorocarbons (HFCs) at the end of the refrigeration and air conditioning equipment life is a priority. The technological development is important to stimulate the F-gas capture, specifically difluoromethane (R-32) and 1,1,1,2-tetrafluoroethane (R-134a), due to their high global warming potential. In this work, the COSMO-RS method is used to analyze the solute-solvent interactions and to determine Henry's constants of R-32 and R-134a in more than 600 ionic liquids. The three most performant ionic liquids were selected on the basis of COSMO-RS calculations, and F-gas absorption equilibrium isotherms were measured using gravimetric and volumetric methods. Experimental results are in good agreement with COSMO-RS predictions, with the ionic liquid tributyl(ethyl)phosphonium diethyl phosphate, [P2444][C2C2PO4], being the salt presenting the highest absorption capacities in molar and mass units compared to salts previously tested. The other two ionic liquids selected, trihexyltetradecylphosphonium glycinate, [P66614][C2NO2], and trihexyl(tetradecyl)phosphonium 2-cyano-pyrrole, [P66614][CNPyr], may be competitive as far as their absorption capacities are concerned. Future works will be guided on evaluating the performance of these ionic liquids at an industrial scale by means of process simulations, in order to elucidate the role in process efficiency of other relevant absorbent properties such as viscosity, molar weight, or specific heat.

4.
Environ Sci Technol ; 54(19): 12784-12794, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32822151

RESUMO

The environmental impact of fluorinated gases (F-gases) necessitates the development of green technologies to mitigate them. Fluorinated ionic liquids (FIL/ILs) emerged as an alternative absorbent due to their unique and exceptional properties. In this work, a COSMO-based/Aspen Plus methodology was used to evaluate the performance of FIL/ILs as absorbents in the process scale of two F-gases: 1,1,1,2-tetrafluoroethane (R-134a) and difluoromethane (R-32). Results of the absorption column in equilibrium mode revealed that the behavior of FIL/ILs is similar under the same conditions, reaching higher efficiencies in the case of absorbing R-134a at a high F-gas partial pressure. Rate-based calculations in packing column demonstrated a kinetic control with highly viscous FIL/ILs, revealing higher performance differences between FIL/IL absorbents. The regeneration stage was also evaluated in near-industrial conditions. Operating conditions of the absorption column were optimized with a column of height 10 m and diameter ranging from 1.1 to 1.2 m at 10 bar total pressure, reaching 90% F gas recovery with an L/G range of 6-10. Finally, preliminary economic analysis revealed operating costs to recover 90% of F-gas of 70 $/ton (R-134a) and 130 $/ton (R-32) with the FIL/IL that revealed the best behavior, 1-ethyl-3-methylimidazolium triflate.


Assuntos
Líquidos Iônicos , Gases , Cinética
5.
Phys Chem Chem Phys ; 21(12): 6362-6380, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30838371

RESUMO

Fluorinated ionic liquids (FILs) are a unique family of ionic liquids with remarkable properties, including the formation of three nano-segregated domains, which are very attractive for several emerging applications. However, the amount of available experimental data to fully characterize them is very scarce. We propose a systematic methodology to build FIL transferable molecular models within the soft-SAFT framework to describe the behaviour of FILs and their mixtures. A total of 38 FILs (pyridinium- and imidazolium-based FILs conjugated with fluorinated anions such as [N(CF3SO2)2]-, [CF3SO3]-, [CF3CO2]-, [C4F9SO3]- and [C4F9CO2]-) have been modelled for this purpose using available data, paying special attention to the physical meaning of the parameters. The models are used to obtain molecular insights into the influence of the anion and cation molecular structures on the thermophysical properties of the FILs. It is concluded that the anion and anion fluorination are the leading features in the thermophysical properties investigated, as captured by soft-SAFT. Models for three FILs not included in the parametrization study were built from the transferable parameters, in excellent agreement with experimental data, underlining the robustness of the soft-SAFT approach. The methodology presented here allows a direct connection between the molecular characteristics of the FILs, the influence on their behaviour, and how this can be captured by a molecular-based equation of state. The procedure allows assembling FIL models with high predictive capabilities in an intuitive way regarding the process of parametrization from the molecular structure, allowing us to characterize their thermophysical behaviour where limited experimental data are available.

6.
BMC Public Health ; 19(1): 904, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286922

RESUMO

BACKGROUND: On an absolute basis, Argentina is the country with the largest affected population with Chagas Disease (ChD). This constitutes a significant public health issue. As a consequence of Argentina's migratory patterns, there has been a significant increase of affected population in urban centers. An innovative project for early diagnosis and timely treatment of ChD was designed for Municipal Primary Care Facilities of La Plata City, a non- endemic area, in line with a proposal from the Pan-American Health Organization. The project was a public -private intervention. The objectives of this study were to demonstrate the feasibility of the primary healthcare level for early diagnosis and timely treatment of ChD; to design and implement a tailor made program and to innovate in a public-private association. METHODS: The healthcare barriers for early diagnosis and timely treatment for the population with ChD of La Plata were analyzed. The four dimensions described by Peters et al. (Ann N Y Acad Sci 1136:161-71, 2008) were used. The baseline was measured during a previous pilot project and the same items were evaluated at the end of 2017. The model from Damschroder et al. (Implement Sci 4:50, 2009) was used during the implementation process. RESULTS: With all the information gathered during this investigation, a "patient-centered" model was designed. During the program, 17,894 people were serologically tested for ChD, 1,394 were positive and 1,035 were treated. Additionally, 3,750 children from 46 public schools were evaluated for risk factors of ChD. CONCLUSIONS: This project showed the feasibility of the primary healthcare level for early diagnosis and timely treatment of ChD. Tailor made programs and public-private associations should be considered for vulnerable populations in emerging economies in order to enhance efforts and obtain better results. This program may be replicated in other countries of Latin America were Chagas is a main public health issue and, with the corresponding adaptations, for other neglected diseases as well.


Assuntos
Doença de Chagas/diagnóstico , Atenção Primária à Saúde/métodos , Saúde Pública/métodos , Parcerias Público-Privadas , Adolescente , Adulto , Argentina/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/terapia , Criança , Diagnóstico Precoce , Estudos de Viabilidade , Feminino , Implementação de Plano de Saúde , Humanos , Masculino , Projetos Piloto , Fatores de Risco , Instituições Acadêmicas , Tempo para o Tratamento , População Urbana , Adulto Jovem
7.
Rev Panam Salud Publica ; 42: e69, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31093097

RESUMO

This study evaluated and compared follow-up and adverse drug reaction (ADR) reporting for Chagas disease (CD) patients treated with benznidazole (BZN) by two health teams with different levels of experience, using medical records for 204 patients participating in the first year of a scaled-up public health program for CD case detection and treatment conducted at all 46 primary health care centers in La Plata district, Buenos Aires, Argentina, in 2014. Both teams were experienced in CD patient management and trained in BZN administration, and included senior physicians, but one team had no experience in administering BZN while the other team had three years of experience due to their participation in the program's pilot project. Patients with positive serology for CD were treated with 5 mg/kg/day of BZN for 60 days. Patients' median age was 35 years and 84.3% were female. There was a statistically significant difference in the number of ADRs reported by the experienced versus the inexperienced health teams (18 versus 44 respectively; P < 0.001). Health team experience in administering BZN to CD patients, and treatment duration, were significantly associated with reporting of ADRs (adjusted odds ratios (aORs) 0.340 (95% confidence interval (CI): 0.177-0.652) and 0.967 (CI: 0.942-0.993) respectively). ADR reporting increased with patient age, occurring at the highest frequency (42.9%) in people 50+ years old. All treatment discontinuations (nine) occurred in patients followed up by the inexperienced health team. Level of experience in BZN administration to CD patients was significantly and inversely associated with frequency of ADR reports: inexperienced health team members tended to report more.


El presente estudio evaluó y comparó el seguimiento y la notificación de reacciones adversas medicamentosas (RAM) en pacientes con enfermedad de Chagas tratados con benznidazol por dos equipos de salud con diferentes niveles de experiencia, mediante el uso de los expedientes médicos de 204 pacientes que participaron en el primer año de un programa de salud pública ampliado para la detección de casos de enfermedad de Chagas y su tratamiento, realizado en los 46 centros de atención primaria de salud del distrito de La Plata (Buenos Aires) en el 2014. Ambos equipos tenían experiencia en la atención de pacientes con enfermedad de Chagas, estaban capacitados en la administración de benznidazol e incluían médicos experimentados, pero uno de los equipos nunca había usado benznidazol, mientras que el otro tenía tres años de experiencia por su participación en el proyecto piloto del programa. Los pacientes con pruebas serológicas positivas para la enfermedad de Chagas recibieron 5 mg/kg/día de benznidazol durante 60 días. La mediana de edad de los pacientes era de 35 años y 84,3% eran mujeres. Hubo una diferencia estadísticamente significativa entre el número de reacciones adversas medicamentosas notificadas por el equipo de salud experimentado y el equipo sin experiencia (18 y 44, respectivamente; P<0.001). Tanto la experiencia de los equipos de salud en la administración de benznidazol a los pacientes con enfermedad de Chagas como la duración del tratamiento se asociaron significativamente con la notificación de reacciones adversas medicamentosas (razones de posibilidades ajustadas, 0,340; intervalo de confianza de 95% [IC]: 0,177­0,652; y 0,967, IC: 0,942­0,993, respectivamente). La notificación de reacciones adversas medicamentosas aumentó a mayor edad de los pacientes; la frecuencia máxima (42,9%) se observó en las personas mayores de 50 años. Todas las interrupciones del tratamiento (nueve) fueron en pacientes atendidos por el equipo de salud sin experiencia. El nivel de experiencia en la administración de benznidazol a los pacientes con enfermedad de Chagas mostró una asociación significativa e inversa con la frecuencia de notificación de reacciones adversas medicamentosas: los miembros del equipo de salud sin experiencia tendieron a notificar más reacciones.


Neste estudo foram analisados e comparados dados notificados de reação adversa medicamentosa e de acompanhamento de pacientes com doença de Chagas tratados com benznidazol (BZN) por dois grupos de profissionais da saúde com níveis de experiência distintos. Os dados foram obtidos dos prontuários médicos de 204 pacientes que participaram do primeiro ano de um programa expandido de saúde pública para detecção de casos e tratamento da doença de Chagas implantado nas 46 unidades básicas de saúde do distrito de La Plata em Buenos Aires, Argentina, em 2014. Ambos os grupos eram formados por médicos mais graduados e profissionais com experiência na conduta de pacientes com doença de Chagas e capacitados em administrar BZN, porém um dos grupos era inexperiente em administrar BZN enquanto o outro contava com experiência de três anos por ter participado do projeto-piloto do programa. Os pacientes com sorologia positiva para doença de Chagas foram tratados com 5 mg/kg/dia de BZN por 60 dias. A mediana de idade foi 35 anos e 84,3% dos pacientes eram do sexo feminino. Verificou-se uma diferença estatisticamente significativa no número de reações adversas medicamentosas notificadas pelo grupo experiente em relação ao grupo inexperiente (18 vs. 44, respectivamente; P < 0.001). Ter experiência em administrar BZN aos pacientes com doença de Chagas e a duração do tratamento foram fatores significativamente associados à notificação de reação adversa medicamentosa (razão de chances ajustada [aOR] 0,340, intervalo de confiança de 95% [IC 95%] 0,177­0,652 e aOR 0,967, IC 95% 0,942­0,993, respectivamente). A notificação de reação adversa medicamentosa aumentou de acordo com a idade do paciente, ocorrendo com maior frequência (42,9%) nos pacientes acima de 50 anos. Os 9 casos de interrupção do tratamento ocorreram em pacientes acompanhados pelo grupo inexperiente. O nível da experiência em administrar BZN aos pacientes com doença de Chagas teve uma associação significativa e inversa com a frequência de notificação de reação adversa medicamentosa: os integrantes do grupo inexperiente tenderam a notificar mais.

8.
Chemphyschem ; 18(15): 2012-2023, 2017 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-28474438

RESUMO

Fluorinated ionic liquids (FILs) exhibit complex molecular behavior, where three different nanodomains (polar, hydrogenated nonpolar, and fluorinated nonpolar) have been identified by molecular simulations. Given the high number of possible anion/cation combinations, a theoretical tool able to describe the thermophysical properties of these compounds in a systematic, rapid, and accurate manner is highly desirable. We present here a combined experimental-theoretical methodology to obtain the phase, interface, and transport properties of the 1-alkyl-3-methylimidazolium perfluorobutanesulfonate ([Cn C1 Im][C4 F9 SO3 ]) family. In addition to providing new experimental data, an extended version of the Statistical Associating Fluid Theory (soft-SAFT) is used to describe the physicochemical behavior of the [Cn C1 Im][C4 F9 SO3 ] family. A mesoscopic molecular model is built based on the analysis of the chemical structures of these FILs, and supported by quantum chemical calculations to study the charge distribution of the anion, where only the basic physical features are considered. The resulting molecular parameters are related to the molecular weight, providing the basis for thermophysical predictions of similar compounds. The theory is also able to predict the minimum in the surface tension versus the length of the hydrogenated alkyl chain, experimentally found at n=8. The viscosity parameters are also in agreement with the free-volume calculations obtained from experiments.

9.
Langmuir ; 32(24): 6130-9, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27218210

RESUMO

We have investigated, both theoretically and experimentally, the balance between the presence of alkyl and perfluoroalkyl side chains on the surface organization and surface tension of fluorinated ionic liquids (FILs). A series of ionic liquids (ILs) composed of 1-alkyl-3-methylimidazolium cations ([CnC1im] with n = 2, 4, 6, 8, 10, or 12) combined with the perfluorobutanesulfonate anion was used. The surface tensions of the investigated liquid salts are considerably lower than those reported for non-fluorinated ionic liquids. The most surprising and striking feature is the identification, for the first time, of a minimum at n = 8 in the surface tension versus the length of the IL cation alkyl side chain. Supported by molecular dynamics (MD) simulations, it was found that this trend is a result of the competition between the two nonpolar domains (perfluorinated and aliphatic) pointing toward the gas-liquid interface, a phenomenon which occurs in ILs with perfluorinated anions. Furthermore, these ILs present the lowest surface entropy reported to date.

10.
Phys Chem Chem Phys ; 18(36): 25741-50, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27603428

RESUMO

Within ionic liquids, fluorinated ionic liquids (FILs) present unique physico-chemical properties and potential applications in several fields. However, the melting point of these neoteric compounds is usually higher due to the presence of fluorine atoms. This drawback may be resolved by, for instance, mixing different FILs to create eutectic mixtures. In this work, binary mixtures of fluoro-containing and fluorinated ionic liquids were considered with the aim of decreasing their melting temperatures as well as understanding and characterizing these mixtures and their phase transitions. Five FILs were selected, allowing the investigation of four binary mixtures, each of them with a common ion. Their solid-liquid and solid-solid equilibria were studied by differential scanning calorimetry and the non-ideality of the mixtures was investigated. Overall, a variety of solid-liquid equilibria with systems exhibiting eutectic behavior, polymorphs with solid-solid phase transitions, and the formation of intermediate compounds and solid solutions were surprisingly found. In addition to these intriguing behaviours, novel FILs with lower melting temperatures were obtained by the formation of binary systems, thus enlarging the application range of FILs at lower temperatures.

12.
Langmuir ; 31(4): 1283-95, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25580898

RESUMO

In this work, novel and nontoxic fluorinated ionic liquids (FILs) that are totally miscible in water and could be used in biological applications, where fluorocarbon compounds present a handicap because their aqueous solubility (water and biological fluids) is in most cases too low, have been investigated. The self-aggregation behavior of perfluorosulfonate-functionalized ionic liquids in aqueous solutions has been characterized using conductometric titration, isothermal titration calorimetry (ITC), surface tension measurements, dynamic light scattering (DLS), viscosity and density measurements, and transmission electron microscopy (TEM). Aggregation and interfacial parameters have been computed by conductimetry, calorimetry, and surface tension measurements in order to study various thermodynamic and surface properties that demonstrate that the aggregation process is entropy-driven and that the aggregation process is less spontaneous than the adsorption process. The novel perfluorosulfonate-functionalized ILs studied in this work show improved surface activity and aggregation behavior, forming distinct self-assembled structures.

13.
Phys Chem Chem Phys ; 15(41): 18138-47, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24061089

RESUMO

The subject of ionicity has been extensively discussed in the last decade, due to the importance of understanding the thermodynamic and thermophysical behaviour of ionic liquids. In our previous work, we established that ionic liquids' ionicity could be improved by the dissolution of simple inorganic salts in their milieu. In this work, a comparison between the thermophysical properties of two binary systems of ionic liquid + inorganic salt is presented. The effect of the ammonium thiocyanate salt on the ionicity of two similar ionic liquids, 1-ethyl-3-methylimidazolium ethylsulfonate and ethylsulfate, is investigated in terms of the related thermophysical properties, such as density, viscosity and ionic conductivity in the temperature range 298.15-323.15 K. In addition, spectroscopic (NMR and Raman) and molecular dynamic studies were conducted in order to better understand the interactions that occur at a molecular level. The obtained results reveal that although the two anions of the ionic liquid exhibit similar chemical structures, the presence of one additional oxygen in the ethylsulfate anion has a major impact on the thermophysical properties of the studied systems.

14.
Pharmaceutics ; 15(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36678790

RESUMO

Proteins are inherently unstable, which limits their use as therapeutic agents. However, the use of biocompatible cosolvents or surfactants can help to circumvent this problem through the stabilization of intramolecular and solvent-mediated interactions. Ionic liquids (ILs) have been known to act as cosolvents or surface-active compounds. In the presence of proteins, ILs can have a beneficial effect on their refolding, shelf life, stability, and enzymatic activities. In the work described herein, we used small-angle X-ray scattering (SAXS) to monitor the aggregation of different concentrations of ILs with protein models, lysozyme (Lys) and bovine serum albumin (BSA), and fluorescence microscopy to assess micelle formation of fluorinated ILs (FILs) with Lys. Furthermore, coarse-grained molecular dynamics (CG-MD) simulations provided a better understanding of Lys-FIL interactions. The results showed that the proteins maintain their globular structures in the presence of FILs, with signs of partial unfolding for Lys and compaction for BSA with increased flexibility at higher FIL concentrations. Lys was encapsulated by FIL, thus reinforcing the potential of ILs to be used in the formulation of protein-based pharmaceuticals.

15.
Glob Chall ; 7(1): 2200107, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36618101

RESUMO

The research on porous materials for the selective capture of fluorinated gases (F-gases) is key to reduce their emissions. Here, the adsorption of difluoromethane (R-32), pentafluoroethane (R-125), and 1,1,1,2-tetrafluoroethane (R-134a) is studied in four metal-organic frameworks (MOFs: Cu-benzene-1,3,5-tricarboxylate, zeolitic imidazolate framework-8, MOF-177, and MIL-53(Al)) and in one zeolite (ZSM-5) with the aim to develop technologies for the efficient capture and separation of high global warming potential blends containing these gases. Single-component sorption equilibria of the pure gases are measured at three temperatures (283.15, 303.15, and 323.15 K) by gravimetry and correlated using the Tóth and Virial adsorption models, and selectivities toward R-410A and R-407F are determined by ideal adsorption solution theory. While at lower pressures, R-125 and R-134a are preferentially adsorbed in all materials, at higher pressures there is no selectivity, or it is shifted toward the adsorption R-32. Furthermore, at high pressures, MOF-177 shows the highest adsorption capacity for the three F-gases. The results presented here show that the utilization of MOFs, as tailored made materials, is promising for the development of new approaches for the selective capture of F-gases and for the separation of blends of these gases, which are used in commercial refrigeration.

16.
Nanomaterials (Basel) ; 12(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35335706

RESUMO

Phenylketonuria (PKU) is an autosomal recessive disease caused by deficient activity of human phenylalanine hydroxylase (hPAH), which can lead to neurologic impairments in untreated patients. Although some therapies are already available for PKU, these are not without drawbacks. Enzyme-replacement therapy through the delivery of functional hPAH could be a promising strategy. In this work, biophysical methods were used to evaluate the potential of [N1112(OH)][C4F9SO3], a biocompatible fluorinated ionic liquid (FIL), as a delivery system of hPAH. The results herein presented show that [N1112(OH)][C4F9SO3] spontaneously forms micelles in a solution that can encapsulate hPAH. This FIL has no significant effect on the secondary structure of hPAH and is able to increase its enzymatic activity, despite the negative impact on protein thermostability. The influence of [N1112(OH)][C4F9SO3] on the complex oligomerization equilibrium of hPAH was also assessed.

17.
Nanomaterials (Basel) ; 12(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35683707

RESUMO

Interferon-alpha 2b (IFN-α 2b) is a therapeutic protein used for the treatment of cancer, viral infections, and auto-immune diseases. Its application is hindered by a low bioavailability and instability in the bloodstream, and the search for new strategies for a target delivery and stabilization of IFN-α 2b to improve its therapeutic efficacy is crucial. Fluorinated ionic liquids (FILs) are promising biomaterials that: (i) can form self-assembled structures; (ii) have complete miscibility in water; and (iii) can be designed to have reduced toxicity. The influence of IFN-α 2b in the aggregation behaviour of FILs and the interactions between them were investigated through conductivity and surface tension measurements, and using electron microscopic and spectroscopy techniques to study FILs feasibility as an interferon-alpha 2b delivery system. The results show that the presence of IFN-α 2b influences the aggregation behaviour of FILs and that strong interaction between the two compounds occurs. The protein might not be fully encapsulated by FILs. However, the FIL can be tailored in the future to carry IFN-α 2b by the formation of a conjugate, which prevents the aggregation of this protein. This work constitutes a first step toward the design and development of FIL-based IFN-α 2b delivery systems.

18.
Gels ; 8(9)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36135306

RESUMO

Gelatin is a popular biopolymer for biomedical applications due to its harmless impact with a negligible inflammatory response in the host organism. Gelatin interacts with soluble molecules in aqueous media as ionic counterparts such as ionic liquids (ILs) to be used as cosolvents to generate the so-called Ionogels. The perfluorinated IL (FIL), 1-ethyl-3-methylpyridinium perfluorobutanesulfonate, has been selected as co-hydrosolvent for fish gelatin due to its low cytotoxicity and hydrophobicity aprotic polar structure to improve the drug aqueous solubility. A series of FIL/water emulsions with different FIL content and their corresponding shark gelatin/FIL Ionogel has been designed to enhance the drug solubility whilst retaining the mechanical structure and their nanostructure was probed by simultaneous SAXS/WAXS, FTIR and Raman spectroscopy, DSC and rheological experiments. Likewise, the FIL assisted the solubility of the antitumoural Doxorubicin whilst retaining the performing mechanical properties of the drug delivery system network for the drug storage as well as the local administration by a syringe. In addition, the different controlled release mechanisms of two different antitumoral such as Doxorubicin and Mithramycin from two different Ionogels formulations were compared to previous gelatin hydrogels which proved the key structure correlation required to attain specific therapeutic dosages.

19.
Nanomedicine (Lond) ; 16(1): 63-80, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33356551

RESUMO

In drug discovery and drug development, it is estimated that around 40% of commercialized and 90% of under-study drugs have inadequate pharmaceutical properties, severely impairing its therapeutic efficacy. Thus, there is a strong demand to find strategies to enhance the delivery of such drugs. Ionic liquids are a novel class of liquids composed of a combination of organic salts that are of particular interest alone or in combination with drug delivery systems. This review is focused on the recent efforts using ionic liquids in drug solubility, formulation and drug delivery with specific emphasis on nanotechnology. The latest developments using hybrid delivery systems obtained upon the combination of drug delivery systems and ionic liquids will also be addressed.


Assuntos
Líquidos Iônicos , Sistemas de Liberação de Medicamentos , Nanotecnologia , Preparações Farmacêuticas , Solubilidade
20.
Nanomaterials (Basel) ; 11(3)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33671036

RESUMO

In this work, polymeric membranes functionalized with ionic liquids (ILs) and exfoliated graphene nanoplatelets (xGnP) were developed and characterized. These membranes based on graphene ionanofluids (IoNFs) are promising materials for gas separation. The stability of the selected IoNFs in the polymer membranes was determined by thermogravimetric analysis (TGA). The morphology of membranes was characterized using scanning electron microscope (SEM) and interferometric optical profilometry (WLOP). SEM results evidence that upon the small addition of xGnP into the IL-dominated environment, the interaction between IL and xGnP facilitates the migration of xGnP to the surface, while suppressing the interaction between IL and Pebax®1657. Fourier transform infrared spectroscopy (FTIR) was also used to determine the polymer-IoNF interactions and the distribution of the IL in the polymer matrix. Finally, the thermodynamic properties and phase transitions (polymer-IoNF) of these functionalized membranes were studied using differential scanning calorimetry (DSC). This analysis showed a gradual decrease in the melting point of the polyamide (PA6) blocks with a decrease in the corresponding melting enthalpy and a complete disappearance of the crystallinity of the polyether (PEO) phase with increasing IL content. This evidences the high compatibility and good mixing of the polymer and the IoNF.

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