RESUMEN
The use of surfactants is crucial for the prevention and control of coal dust pollution in coal mining operation areas, yet there still exist many challenges in the control of coal dust pollution. In this paper, the green biomass-based amino acid surfactant sodium myristoyl glutamate (SMG) and the anionic surfactant sodium α-alkenyl sulfonate (AOS) were selected to investigate the improvement of coal dust wettability by single and binary solutions from the macroscopic and microscopic perspectives. Molecular simulations were used to reveal the microscopic mechanism of the wettability of coal dust by the different solutions. Experimental measurements showed that the contact angle of the AOS + SMG aqueous solution was as low as 13.8° on a coal surface. Coating the coal dust with the AOS + SMG solution reduced the surface tension by 12.02% compared to coating the coal with a single component solution. Additionally, the use of the binary AOS + SMG solution increased the hydrophilic group content in the coating by 11.77% compared to a single component solution, and the linkage between hydrophilic groups was enhanced, which pulls the water molecules to wet the coal dust. These research results should provide a new way to promote more environmentally friendly coal dust pollution control technology.
Asunto(s)
Carbón Mineral , Polvo , Tensoactivos , Polvo/análisis , Tensoactivos/química , Aminoácidos/química , Humectabilidad , Alcanosulfonatos/química , Minas de Carbón , Contaminación Ambiental/prevención & controlRESUMEN
In this article, the binding interactions between bovine serum albumin (BSA) and three 1-alkylsulfonates, namely sodium 1-dodecanesulfonate, sodium 1-decanesulfonate, and sodium 1-octanesulfonate, have been thoroughly investigated. The study employed various experimental techniques such as isothermal titration calorimetry (ITC), steady-state fluorescence spectroscopy (SF), circular dichroism spectroscopy (CD), and molecular dynamics-based simulations. The objective was to understand the influence of the alkyl chain length of the investigated ligands on several aspects, including the strength of the interaction, the stoichiometry of the resulting complexes, the number of BSA binding sites, and the underlying mechanisms of binding. Notably, the study also demonstrated that sodium dodecyl sulfate (S12S) can serve as an effective site marker for BSA when studying ligands with similar structural and topological features. These findings may have significant implications for enhancing our understanding of the interactions between small amphiphilic molecules and proteins.
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Interacciones Hidrofóbicas e Hidrofílicas , Unión Proteica , Albúmina Sérica Bovina , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/metabolismo , Animales , Bovinos , Sitios de Unión , Simulación de Dinámica Molecular , Ligandos , Alcanosulfonatos/química , Termodinámica , Espectrometría de FluorescenciaRESUMEN
Bacteria have evolved to utilize alternative organosulfur sources when sulfur is limiting. The SsuE/SsuD and MsuE/MsuD enzymes expressed when sulfur sources are restricted, are responsible for providing specific bacteria with sulfur in the form of alkanesulfonates. In this study, we evaluated why two structurally and functionally similar FMNH2-dependent monooxygenase enzymes (MsuD and SsuD) are needed for the acquisition of alkanesulfonates in some bacteria. In desulfonation assays, MsuD was able to utilize the entire range of alkanesulfonates (C1-C10). However, SsuD was not able to utilize smaller alkanesulfonate substrates. Interestingly, SsuD had a similar binding affinity for methanesulfonate (MES) (15 ± 1 µM) as MsuD (12 ± 1 µM) even though SsuD was not able to catalyze the desulfonation of the MES substrate. SsuD and MsuD showed decreased proteolytic susceptibility in the presence of FMNH2 with MES and octanesulfonate (OCS). Tighter loop closure was observed for the MsuD/FMNH2 complex with MES and OCS compared to SsuD under comparable conditions. Analysis of the SsuD/FMNH2/MES structure using accelerated molecular dynamics simulations found three different conformations for MES, demonstrating the instability of the bound structure. Even when MES was bound in a similar fashion to OCS within the active site, the smaller alkane chain resulted in a shift of FMNH2 so that it was no longer in a position to catalyze the desulfonation of MES. The active site of SsuD requires a longer alkane chain to maintain the appropriate architecture for desulfonation.
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Proteínas de Escherichia coli , Dominio Catalítico , Proteínas de Escherichia coli/química , Oxigenasas de Función Mixta/metabolismo , Alcanosulfonatos/química , Alcanosulfonatos/metabolismo , AzufreRESUMEN
Hydroxyalkylsulfonates may contribute significantly to atmospheric particles; however, their hygroscopic properties and cloud condensation nuclei (CCN) activities remain unknown. In this study, three complementary techniques were utilized to examine the hygroscopicity of sodium hydroxymethanesulfonate (NaHMS), sodium 2-hydroxyethylsulfonate (NaHES), and ammonium 2-hydroxyethylsulfonate (NH4HES) under subsaturated and supersaturated environments. The mass changes in the three hydroxyalkylsulfonates at different relative humidities at 25 °C were examined by a vapor sorption analyzer, and the mass growth factors were measured to be 3.25 ± 0.01 for NaHMS, 3.32 ± 0.02 for NaHES, and 3.34 ± 0.04 for NH4HES at 90% RH. Their hygroscopic growth was investigated by a humidity tandem differential mobility analyzer, and hygroscopic growth factors were 1.78 ± 0.02 for NaHMS, 1.71 ± 0.02 for NaHES, and 1.68 ± 0.03 for NH4HES at 90% RH. Furthermore, the CCN activities of NaHMS, NaHES, and NH4HES were explored, and their single hygroscopicity parameters (κccn) were measured to be 0.649 ± 0.097 for NaHMS, 0.559 ± 0.069 for NaHES, and 0.434 ± 0.073 for NH4HES. In addition, the hygroscopic growth and CCN activities of binary mixtures of ammonium sulfate with one of the three hydroxyalkylsulfonates were also examined.
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Alcanosulfonatos/química , Gases , Aerosoles , Sulfato de Amonio , Humedad , HumectabilidadRESUMEN
Herein, we report a series of di-anionic supramolecular self-associating amphiphiles (SSAs). We elucidate the antimicrobial properties of these SSAs against both methicillin resistant Staphylococcus aureus and Escherichia coli. In addition, we show this class of compound to form both intra- and intermolecular hydrogen bonded macrocyclic structures in the solid state.
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Alcanosulfonatos/farmacología , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Compuestos de Fenilurea/farmacología , Tensoactivos/farmacología , Alcanosulfonatos/química , Antibacterianos/química , Enlace de Hidrógeno , Pruebas de Sensibilidad Microbiana , Compuestos de Fenilurea/química , Espectroscopía de Protones por Resonancia Magnética , Tensoactivos/químicaRESUMEN
Liquid detergent has an increasing demand in North America, Western Europe, and Southeast Asia countries owing to its convenience to use and efficiency to clean. Alpha methyl ester sulfonates (α-MES), an anionic surfactant derived from palm oil based methyl ester, was reported to have lower manufacturing cost, good detergency with less dosage, excellent biodegradability, higher tolerance to hard water, and lower eco-toxicity as compared to linear alkylbenzene sulfonates (LABS). LABS was known as the workhorse of the detergent industry in the 20th century. Although palm-based α-MES was successfully used as the sole surfactant in powder detergent, there are still some unsettled technical issues related to phase stability and viscosity when using this anionic surfactant in heavy-duty laundry liquid detergent formulations. This paper will review not only the market overview of detergents, the application and performance of green surfactants in laundry detergents but also will highlight the technical issues related to the application of palm-based α-MES in laundry liquid detergent and some of the possible methods to overcome the formulation adversities.
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Alcanosulfonatos/química , Detergentes/química , Tensoactivos/química , Alcanosulfonatos/toxicidad , Animales , Biodegradación Ambiental , Detergentes/toxicidad , Ésteres/química , Ésteres/toxicidad , Glucolípidos/química , Glucolípidos/toxicidad , Tecnología Química Verde , Ésteres del Ácido Sulfúrico/química , Ésteres del Ácido Sulfúrico/toxicidad , Tensoactivos/toxicidad , ViscosidadRESUMEN
Recently, flexible and wearable sensors assembled from conductive hydrogels have attracted widespread attention. However, it is still a great challenge to make hydrogels with sufficient mechanical properties, self-adhesiveness and strain sensitivity. Here, a strong, tough, and self-adhesive hydrogel is successfully fabricated by a one-pot method, which introducing chitosan and 2-acrylamido-2-methylpropane sulfonic acid into the polyacrylamide network. The hydrogels exhibited adhesion (the peel strength reaches 798 N/m), mechanical property (The breaking strength and strain can reach 111 kPa and 2839%) and electrical conductivity (conductivity up to 0.0848 S/cm), which are suitable for wearable epidermal sensors. Besides, the hydrogels also possessed transparency. Therefore, this work would provide a novel insight on the fabrication of multi-functional self-adhesive hydrogel sensors.
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Quitosano/química , Hidrogeles/química , Monitoreo Fisiológico/métodos , Dispositivos Electrónicos Vestibles , Acrilamidas/química , Adhesividad , Alcanosulfonatos/química , Fuerza Compresiva , Módulo de Elasticidad , Conductividad Eléctrica , Humanos , Ensayo de Materiales , Monitoreo Fisiológico/instrumentación , Movimiento (Física) , Polimerizacion , Resistencia a la Tracción , Tecnología InalámbricaRESUMEN
Particularly, chitosan (Cs) loaded with drug cannot pass through the colonic region, often leading in the bursting drug release in the stomach due to its solubility in gastric contents. The novelty of the current article is to solve this limitation by performing gamma irradiation cross-linking of Cs with two anionic polymers of (acrylic acid)-co-(2-acrylamido-2-methylpropane-sulfonic acid) (AAc/AMPS) to give amphiphilic hydrogel. The shifted in the characteristic FTIR peaks of Cs in the (Cs/AAc/AMPS) confirm the exits of inter-molecular interactions that make Cs and (AAc/AMPS) are miscible. Swelling experiments under different pH indicated that the (Cs/AAc/AMPS) hydrogels were significantly sensitive to pH change. The results give the possibility to use the obtained (Cs/AAc/AMPS) hydrogel on drug delivery system. The in vitro Fluorouracil (5-FU) releasing from (Cs/AAc/AMPS) matrix was examined under the influence of pH1 and pH7.The results confirmed the hydrogels capability to release 96 % of 5-FU drug at pH 7 after 7 h.
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Quitosano/síntesis química , Neoplasias del Colon/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Rayos gamma , Hidrogeles/síntesis química , Polímeros/síntesis química , Tensoactivos/síntesis química , Acrilamidas/química , Acrilatos/química , Alcanosulfonatos/química , Antimetabolitos Antineoplásicos/química , Quitosano/química , Reactivos de Enlaces Cruzados , Liberación de Fármacos , Fluorouracilo/química , Humanos , Hidrogeles/química , Concentración de Iones de Hidrógeno , Cinética , Polímeros/química , Tensoactivos/química , Agua/químicaRESUMEN
BACKGROUND: In Doxil®, PEGylated nanoliposomes are created by hydration of the lipids in ammonium sulfate, and are remotely loaded with doxorubicin by a transmembrane ammonium gradient. The ammonium sulfate is then removed from the external aqueous phase, surrounding the liposomes, and replaced by an isoosmotic sucrose solution in 10 mM histidine buffer at pH 6.5. METHODS: We prepared PEGylated liposomal doxorubicin (PLD) with a series of ammonium monovalent salts that after remote loading became the intraliposome doxorubicin counteranions. We analyzed the liposomes by solution X-ray scattering, differential scanning calorimetry, and electron micropscopy. RESULTS: PLDs prepared with sulfonic acid derivatives as counteranion exhibited chemical and physical stabilities. We determined the effect of these ammonium salt counteranions on the structure, morphology, and thermotropic behavior of the PEGylated nanoliposomes, formed before and after doxorubicin loading, and the bulk properties of the doxorubicin-counteranion complexes. By comparing the structure of the doxorubicin complexes in the bulk and inside the nanoliposomes, we revealed the effect of confinement on the structure and doxorubicin release rate for each of the derivatives of the ammonium sulfonic acid counteranions. CONCLUSIONS: We found that the extent and direction of the doxorubicin confinement effect and its release rate were strongly dependent on the type of counteranion. The counteranions, however, neither affected the structure and thermotropic behavior of the liposome membrane, nor the thickness and density of the liposome PEG layers. In an additional study, it was demonstrated that PLD made with ammonium-methane sulfonate exhibit a much lower Hand and Foot syndrome. GENERAL SIGNIFICANCE: The structure, physical state, and pharmacokinetics of doxorubicin in PEGylated nanoliposomes, prepared by transmembrane remote loading using gradients of ammonium salts, strongly depend on the counteranions.
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Compuestos de Amonio/química , Antibióticos Antineoplásicos/química , Doxorrubicina/análogos & derivados , Polietilenglicoles/química , Alcanosulfonatos/química , Sulfato de Amonio/química , Aniones/química , Cristalización , Doxorrubicina/química , Mesilatos/químicaRESUMEN
Graphene oxide (GO) crosslinked nanocomposites hydrogels (NCH) of chitosan (CS) and carboxymethyl cellulose (CMC) were synthesized and the feasibility of its application as a versatile adsorbent for the remediation of cationic (methylene blue, MB) as well as anionic (methyl orange, MO) dyes contaminated wastewater was explored. Initially, GO was functionalized with vinyltriethoxysilane which was subsequently used as a chemical crosslinker to synthesize the NCH of CS and CMC (CS/CMC-NCH) with the polymeric mixture of diallyldimethylammonium chloride and 2-acrylamido-2-methyl-1-propanesulfonic acid. About 99% dye was adsorbed from 50 mg/L dye solution of MB dye with 0.4 g/L of CS/CMC-NCH at pH 7, whereas, for MO about 82% dye was adsorbed with 0.6 g/L of CS/CMC-NCH at pH 3. The Adsorption of both dyes is well explained using pseudo-second-order and Langmuir models with the maximum adsorption capacities of 655.98 mgdye/gads for MB and 404.52 mgdye/gads for MO. Thermodynamics studies suggested spontaneous and exothermic nature of the adsorption process with values of ΔS < 0 and ΔH > 0. Furthermore, CS/CMC-NCH showed excellent regeneration capacity for continuous twenty cycles of adsorption-desorption. Therefore, the synthesized CS/CMC-NCH is a versatile adsorbent that can treat both anionic and cationic dyes contaminated wastewater.
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Carboximetilcelulosa de Sodio/química , Quitosano/química , Colorantes/química , Grafito/química , Nanogeles/química , Purificación del Agua/métodos , Acrilamidas/síntesis química , Acrilamidas/química , Adsorción , Alcanosulfonatos/síntesis química , Alcanosulfonatos/química , Compuestos Alílicos/síntesis química , Compuestos Alílicos/química , Aniones/química , Compuestos Azo/química , Cationes/química , Colorantes/análisis , Concentración de Iones de Hidrógeno , Cinética , Azul de Metileno/química , Compuestos de Amonio Cuaternario/síntesis química , Compuestos de Amonio Cuaternario/química , Silanos/química , Termodinámica , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
The purpose of this work was to examine the influence of poly(sodium allyl sulfonate) (PSAS) branches on sizing properties of biological macromolecule (corn starch) for exploring a new anionic starch graft copolymer size (S-g-PSAS). Successful synthesis of S-g-PSAS samples was confirmed by energy dispersive X-ray spectrometer. Viscosity stability, adhesion, film properties and desizability of the samples were also investigated. Compared with HS, improved adhesion to cotton and viscose fibers, viscosity stability and desizability for S-g-PSAS as well as enhanced breaking elongation and bending endurance for S-g-PSAS film were exhibited. With the rise in grafting ratio, bonding forces to both fibers, viscosity stability and desizability of S-g-PSAS and its film properties such as breaking elongation and bending endurance, were gradually enhanced. These results indicated that S-g-PSAS showed potential for the use as a new starch-based size in the sizing of cotton and viscose warps.
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Compuestos Alílicos/química , Fibra de Algodón , Plastificantes/química , Almidón/análogos & derivados , Adhesivos/síntesis química , Alcanosulfonatos/química , Elasticidad , Industria Textil/métodos , Viscosidad , Zea mays/químicaRESUMEN
Here, firstly lignin sulfonate was produced from sulfite liquor provided by Mazandaran wood & paper industries (Chookam). Then, the role of effective parameters including reaction temperature, duration time, and amounts of pyridine and acetic anhydride respectively as the catalyst and the esterification agent on the acetylation rate of lignin sulfonate were studied and the process parameters were optimized through multiple experiments. In this investigation, using 1 g lignin sulfonate, the effect of various levels of temperature (ranged from room temperature to 140 °C), reaction time (12-72 h), pyridine volume (0-30 mL), and acetic anhydride volume (5-30 mL) were evaluated. Based on the results of several esterification processes, the optimal values of temperature and reaction time were obtained to be 100 °C and 48 h, respectively, and the optimal volumes of acetic anhydride and pyridine were 20 mL (with equal amounts). Besides, the characterization tests of lignin sulfonate and acetylated lignin sulfonate were performed using FT-IR and NMR techniques. Also in this paper, the morphology and crystallinity/amorphicity of lignin sulfonate and acetylated lignin sulfonate were examined using SEM images and XRD patterns.
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Alcanosulfonatos/química , Biopolímeros/química , Lignina/química , Sulfitos/química , Anhídridos Acéticos/química , Acetilación , Esterificación , Lignina/síntesis química , Espectroscopía de Resonancia Magnética , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Madera/químicaRESUMEN
Heroin overdose and addiction remain significant health and economic burdens in the world today costing billions of dollars annually. Moreover, only limited pharmacotherapeutic options are available for treatment of heroin addiction. In our efforts to combat the public health threat posed by heroin addiction, we have developed vaccines against heroin. To expand upon our existing heroin-vaccine arsenal, we synthesized new aryl and alkyl sulfonate ester haptens; namely aryl-mono-sulfonate (HMsAc) and Aryl/alkyl-di-sulfonate (H(Ds)2) as carboxyl-isosteres of heroin then compared them to our model heroin-hapten (HAc) through vaccination studies. Heroin haptens were conjugated to the carrier protein CRM197 and the resulting CRM-immunoconjugates were used to vaccinate Swiss Webster mice following an established immunization protocol. Binding studies revealed that the highest affinity anti-heroin antibodies were generated by the HMsAc vaccine followed by the HAc and H(Ds)2 vaccines, respectively (HMsAc > HAcâ«HDs2). However, neither the HMsAc nor H(Ds)2 vaccines were able to generate high affinity antibodies to the psychoactive metabolite 6-acetyl morphine (6-AM), in comparison to the HAc vaccine. Blood brain bio-distribution studies supported these binding results with vaccine efficiency following the trend HAc > HMsAc â« H(Ds)2 The work described herein provides insight into the use of hapten-isosteric replacement in vaccine drug design.
Asunto(s)
Alcanosulfonatos/química , Diseño de Fármacos , Haptenos/química , Heroína/química , Vacunas Sintéticas/inmunología , Animales , Anticuerpos/inmunología , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Encéfalo/metabolismo , Haptenos/inmunología , Heroína/inmunología , Ratones , Vacunas Sintéticas/sangre , Vacunas Sintéticas/metabolismoRESUMEN
Methyl ester sulphonates (MES) have been considered as an alternative green surfactant for the detergent market. Investigation on the purification of methyl ester sulphonates (MES) with various carbon chains of C12, C14, C16 and C16-18 derived from palm methyl ester is of great interest. These MES powders have been repeatedly crystallized with ethanol and the purity of MES has increased to a maximum of 99% active content and 96% crystallinity index without changing the structure. These crystallized MES with high active content have 1.0% to 2.3% moisture content and retained its di-salt content in the range of 5%. The crystallized MES C16 and C16-18 attained excellent flow characteristics. Morphology, structural and its crystallinity analyses showed that the crystals MES had good solubility properties, stable crystal structure (ß polymorphic) and triclinic lateral structure when it is in high active content. The brittleness of MES crystals increased from a ß' to a ß subcell. Crystal with high brittleness has the potential to ease production of powder, which leads to a reduction in the cost of production and improves efficiency.
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Alcanosulfonatos/análisis , Alcanosulfonatos/química , Ésteres/química , Aceite de Palma/química , Tensoactivos/química , Cristalización , PolvosRESUMEN
A novel sulfonated chitosan-derived carbon-based catalyst was successfully prepared via isoamyl nitrite-assisted sulfanilic acid sulfonation, and its catalytic activity was examined using dehydration of fructose. The structural and chemical properties of sulfonated chitosan-derived carbon were characterized by SEM, FTIR, XRD, XPS, element analysis, N2 adsorption-desorption experiment, and acid-base titration experiment. KOH was used as activating agent in the synthesizing of carbon supports, and it was found that properly increasing the dose of KOH during activation stage had a positive effect on the subsequent sulfonation of prepared activated carbon. 4KSCC, with the highest sulfonation degree (2.04 mmol/g), exhibited high performance for the conversion of fructose to HMF in various solvent, and an optimal HMF yield of 80.9% was obtained at 140 °C in 40 min. In addition, the reusability of 4KSCC for fructose dehydration was fairly good.
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Carbono/química , Catálisis , Quitosano/química , Fructosa/química , Furaldehído/análogos & derivados , Alcanosulfonatos/química , Deshidratación , Furaldehído/síntesis química , Solventes/química , Ácidos Sulfanílicos/química , Temperatura , Agua/químicaRESUMEN
Chlorinated polyfluoroalkyl ether sulfonates (trade name F-53B) has been detected in various environmental matrices, and reported to be equally or more toxic than perfluorooctane sulfonate. Efficient sorptive removal of F-53B from water by two types of layered double hydroxides (LDHs), NO3--LDH and sodium dodecyl sulfate modified NO3--LDH (SDS-LDH), was demonstrated in this study. Both LDHs removed F-53B in several minutes and had sorption capacities of over 860 mg/g. SDS-LDH exhibited a greater F-53B uptake than NO3--LDH under the influence of different solution chemistry, including pH 3-11, or in the presence of competing anions or co-contaminants, primarily due to the higher surface areas and the presence of SDS for SDS-LDH. Batch experiments, structural characterization, molecular dynamics simulations, and density functional theory calculations were combined to explore the sorption mechanisms, which mainly include ion exchange (specifically, O-Hâ¯O/F hydrogen bond), C-F/Clâ¯H hydrogen bond, and micellar sorption (occurring at high initial F-53B concentrations). Accordingly, we propose to improve the sorption performance of LDHs by increasing their surface areas and modifying LDHs to produce more hydrogen bond sites, as well as exfoliating LDHs into two dimensional nanosheets to eliminate the steric hindrance for the micellar formation of F-53B or other per- and polyfluoroalkyl substances.
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Alcanosulfonatos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Alcanosulfonatos/análisis , Ácidos Alcanesulfónicos , Fluorocarburos , Hidróxidos/química , Intercambio Iónico , Dodecil Sulfato de Sodio , Soluciones , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
Particles size of disperse dye in dye bath seriously affected its dyeing quality. Here, we prepared a nano disperse dye with average particles size of 94 nm by self-assembly using a hydroxypropyl sulfonated alkali lignin dispersant (HSAL) and azo disperse dye (C.I. disperse Blue 79). The nano disperse dye exhibited excellent dispersion and stability at high temperature (130 °C), the particle size of that was 1.97 µm. The reducing effect of nano dye (azo structure) was decreased to 5.39% and the dye uptake reached up to 94.27%. The interaction mechanism between lignin derivatives dispersant and dye particles was investigated through the adsorption behaviors by employing quartz crystal microbalance with dissipation monitoring and AFM. The higher adsorption amount of HSAL on the dye surface displayed the more viscoelastic adsorption layer than that of sodium lignosulfonate. High sulfonic group attached to the long alkyl chain in HSAL molecules can stretch out to the aqueous phase to provide a strong electrostatic repulsion to disperse dye particles and form the nano disperse dye self-assembly. The present study provided a novel preparation method of nano disperse dye, that would broaden the efficient and value-able utilization of biomass lignin in dyeing and printing field.
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Compuestos Azo/química , Lignina/química , Nanopartículas/química , Adsorción , Alcanosulfonatos/química , Biomasa , Tamaño de la Partícula , Temperatura , Agua/químicaRESUMEN
A fundamental understanding of confined water is crucial for developing selective ion transport and water purification membranes, yet the roles of nanopore geometry and functionality on confined water dynamics remain unresolved. We report the synthesis of perdeuterated ionic alkylsulfonate amphiphiles and their water-induced self-assembly into lyotropic liquid crystal (LLC) mesophases with well-defined, convex, sulfonate-lined nanopores. Quasielastic neutron scattering (QENS) measurements demonstrate that the water self-diffusion coefficients within these sulfonate-lined convex nanopores depend on the hydration level and amphiphile counterion identity (H+, K+, NMe4+). The consistency of the observed counterion-dependent water dynamics trends with those of carboxylate LLCs is rationalized on the basis of similarities in the counterion spatial distributions in the water-filled channels, which we deduce from electron density maps derived from small-angle X-ray scattering (SAXS) analyses. These findings indicate that water diffusion is systematically faster in sulfonate-lined nanopores as compared to carboxylate-lined pores due to weaker water interactions with the softer and more hydrophobic-SO3- functionalities. These molecular-level insights into the relationships between convex pore wall chemical functionalities, hydrated counterions, and confined water diffusion may inform future development of new nanoporous media.
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Alcanosulfonatos/química , Cristales Líquidos/química , Simulación de Dinámica Molecular , Nanoporos , Agua/química , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Difracción de Neutrones , Dispersión del Ángulo PequeñoRESUMEN
Fluorotelomer compounds in landfill leachate can undergo biotransformation under aerobic conditions and act as a secondary source of perfluorocarboxylic acids (PFCAs) to the environment. Very little is known about the role of various microbial communities towards fluorotelomer compounds biotransformation. Using an inoculum prepared from the sediment of a leachate collection ditch, 6:2 fluorotelomer sulfonate (6:2 FTS) biotransformation experiments were carried out. Specific substrates (i.e., glucose, ammonia) and ammonia-oxidizing inhibitor (allylthiourea) were used to produce two experimental runs with heterotrophic (HET) growth only and heterotrophic with ammonia-oxidizing and nitrite- oxidizing bacteria (HET + AOB + NOB). After 10 days, â¼20% of the spiked 6:2 FTS removal was observed in HET + AOB + NOB, compared to â¼7% under HET condition. Higher 6:2 FTS removal in HET + AOB + NOB likely resulted from ammonia monooxygenase enzyme that catalyzes the first step of ammonia oxidation. The HET + AOB + NOB condition also showed higher PFCA (C4-C6) formation (â¼2% of initially spiked 6:2 FTS), possibly due to higher overall bioactivity. Microbial community analysis through 16s rRNA sequencing confirmed that Proteobacteria and Bacteroidetes were the most abundant phyla (>75% relative abundance) under all experimental conditions. High abundance of Actinobacteria (>17%) was observed under the HET + AOB + NOB condition on day 7. Since Actinobacteria can synthesize a wide range of enzymes including monooxygenases, they likely play an important role in 6:2 FTS biotransformation and PFCA production.
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Alcanosulfonatos , Bacterias/metabolismo , Microbiota , Microbiología del Suelo , Contaminantes Químicos del Agua , Alcanosulfonatos/química , Alcanosulfonatos/metabolismo , Amoníaco/metabolismo , Bacterias/clasificación , Bacterias/genética , Nitritos/metabolismo , Oxidación-Reducción , ARN Ribosómico 16S/genética , Contaminantes Químicos del Agua/metabolismoRESUMEN
OBJECTIVE: PPARα/γ dual agonists have been in clinical development for the treatment of metabolic diseases including type 2 diabetes and dyslipidemia. However, severe adverse side effects led to complications in clinical trials. As most of the beneficial effects rely on the compound activity in adipocytes, the selective targeting of this cell type is a cutting-edge strategy to develop safe anti-diabetic drugs. The goal of this study was to strengthen the adipocyte-specific uptake of the PPARα/γ agonist tesaglitazar via NPY1R-mediated internalization. METHODS: NPY1R-preferring peptide tesaglitazar-[F7, P34]-NPY (tesa-NPY) was synthesized by a combination of automated SPPS and manual couplings. Following molecular and functional analyses for proof of concept, cell culture experiments were conducted to monitor the effects on adipogenesis. Mice treated with peptide drug conjugates or vehicle either by gavage or intraperitoneal injection were characterized phenotypically and metabolically. Histological analysis and transcriptional profiling of the adipose tissue were performed. RESULTS: In vitro studies revealed that the tesaglitazar-[F7, P34]-NPY conjugate selectively activates PPARγ in NPY1R-expressing cells and enhances adipocyte differentiation and adiponectin expression in adipocyte precursor cells. In vivo studies using db/db mice demonstrated that the anti-diabetic activity of the peptide conjugate is as efficient as that of systemically administered tesaglitazar. Additionally, tesa-NPY induces adipocyte differentiation in vivo. CONCLUSIONS: The use of the tesaglitazar-[F7, P34]-NPY conjugate is a promising strategy to apply the beneficial PPARα/γ effects in adipocytes while potentially omitting adverse effects in other tissues.