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The stability of aqueous Z inc (Zn) ion energy storage devices is significantly compromised by the instability at the electrode/electrolyte interface, which can result in the growth of Zn dendrites, self‐corrosion, and various other side reactions. Regulating the Zn‐ion （Zn2+) solvation structure through electrolyte additives has been proved to be effective strategy in stabilizing the Zn anode, but the influence of free water on the solvation structure is often lacking in‐depth exploration. Herein, the piperazine‐N,N‐bis(2‐hydroxypropanesulfonic acid) sodium salt (POPSO‐Na) is presented as a multifunctional electrolyte additive, which enhances the stability of the Zn anode by modulating the deposition and stripping environment of Zn2⁺ and limiting the presence of free water in the electrolyte during cycling. Theoretical calculation and experimental results demonstrate that the POPSO‐Na additive can not only replace the structural water around Zn2+ to destroy the original solvation sheath, but also form reverse micelle interface structure to hinder the proton transition and constrain the free water in the electrolyte. Thus, the Zn||Zn battery utilizing the ZnSO4+POPSO‐Na electrolyte exhibits an impressive cycle life of 1600 h at a current density of 1 mA cm−2, achieving an average Coulomb efficiency (CE) of ≈100%, which is significantly better than that observed with the ZnSO4 electrolyte. Moreover, the Zn||Cu battery with ZnSO4+POPSO‐Na electrolyte achieves high stability even after cycling for over 2000 h. [ABSTRACT FROM AUTHOR]

Copyright of China Condiment is the property of China Condiment and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Exhilarating breakthroughs in the treatment of autoimmune diseases through antigen-specific therapies offer new hope for patients. Herein, a novel antigen-specific reverse micelle platform is proposed: blank liposomes prepared with 1, 2-diolyl-sn-glycerol-3-phosphocholine (DOPC) and cholesterol (Chol) are mixed with an aqueous solution of the encapsulated antigens and immunomodulators, lyophilized, and then reconstituted in oil. Subcutaneous injection of 100 μL of a reverse micelle vaccine loaded with 10 μg of MOG35–55 and 30 μg of dexamethasone sodium phosphate (DSP) before experimental autoimmune encephalomyelitis (EAE, a multiple sclerosis model) establishment directly blocked the development of clinical symptoms. Furthermore, the same vaccine delayed and attenuated clinical symptoms in an established mouse model of EAE. Conversely, the reverse micelle vaccine loaded with an unrelated antigen OVA failed to alleviate paralysis in mice, highlighting the crucial aspect of antigen specificity. Dose-dependent effects were observed in both the prevention and treatment of EAE, with clinical scores of 0 being achieved during the treatment at single DSP doses of up to 50 μg at the MOG35–55 dose of 10 μg. The treatment of the reverse micelle vaccine induced Treg cell proliferation, accounting for the tolerance to the pathogenic antigens and improved outcomes. Overall, the designed reverse micelle vaccine provided a universal platform to encapsulate antigens and immunomodulators that restore tolerance of antigens and then demonstrated the therapeutic promise in autoimmune diseases. [ABSTRACT FROM AUTHOR]

Herein, we propose an analytical approach based on intermolecular fluorescent resonant energy transfer (FRET) pairs for the visualization of specific enzyme activity in model biomembranes and in living cells. Cell visualizations with fluorescent confocal laser microscopy usually rely on fluorescent probes, such as Fluorescein isothiocyanate (FITC), Alexa488, Tetramethylrhodamine isothiocyanate (TRITC) and many others. However, for more specific tasks, such as the detection of certain enzymatic activity inside the living cell, the toolbox is quite limited. In the case of enzyme-hydrolases for example, the choice is limited to organic molecules comprising a fluorescent dye (typically, 4-methylumbelliferone (MUmb) or 7-amino-4-methylcoumarin (AMC) derivatives) and a fluorescence quencher, bound via an enzyme-sensitive linker—so that when the linker is degraded, the fluorescent signal increases. Unfortunately, both MUmb and AMC are quenched and have a relatively low quantum yield in cells, and their excitation and emission ranges overlap with that of intracellular fluorophores, often producing a strong background noise. R6G, on the other hand, has excellent quantum yield apart from intracellular fluorophores, but there are no efficient quenchers that could be chemically linked to R6G. Herein, we show that R6G is able to form intermolecular FRET pairs with MUmb or AMC, with the latter serving as fluorescence donors. This yields a combination of R6G's excellent fluorescence properties with a possibility to use an enzyme-sensitive linker in MUTMAC or AMC derivatives. This phenomenon was initially discovered in a model system, reversed micelles, where the donor, the acceptor, and the enzyme are forced to be in close proximity to each other, so that proximity could serve as an explanation for the intermolecular FRET effect. Surprisingly enough, the phenomenon has been reproduced in living cells. Moreover, we were able to create working intermolecular donor–acceptor FRET pairs for several different enzymes, including chymotrypsin, phosphatase, and asparaginase. This appears counterintuitive, as besides the overlap of the emission spectra of the donor and the absorption spectra of the acceptor, there are other criteria for the FRET effect, including the convergence of two fluorophores at a distance of about 1–10 nm, and the orientation of their dipoles at a certain angle, which is difficult to imagine in a bulk system like a living cell. We hypothesize that FRET-enabling donor–acceptor interaction may be taking place at the inner surface of the lipid bilayer, to which both donor and acceptor molecules would likely have an affinity. This hypothesis would require a more detailed investigation. Therefore, we have shown that the method suggested has good potential in the visualization of enzyme functioning inside living cells, which is often a challenging task. Shifting of the fluorescence signal to the long-wavelength region would increase the signal selectivity, making it easily distinguishable from autofluorescence. [ABSTRACT FROM AUTHOR]

Herein, we propose an analytical approach based on intermolecular fluorescent resonant energy transfer (FRET) pairs for the visualization of specific enzyme activity in model biomembranes and in living cells. Cell visualizations with fluorescent confocal laser microscopy usually rely on fluorescent probes, such as Fluorescein isothiocyanate (FITC), Alexa488, Tetramethylrhodamine isothiocyanate (TRITC) and many others. However, for more specific tasks, such as the detection of certain enzymatic activity inside the living cell, the toolbox is quite limited. In the case of enzyme-hydrolases for example, the choice is limited to organic molecules comprising a fluorescent dye (typically, 4-methylumbelliferone (MUmb) or 7-amino-4-methylcoumarin (AMC) derivatives) and a fluorescence quencher, bound via an enzyme-sensitive linker—so that when the linker is degraded, the fluorescent signal increases. Unfortunately, both MUmb and AMC are quenched and have a relatively low quantum yield in cells, and their excitation and emission ranges overlap with that of intracellular fluorophores, often producing a strong background noise. R6G, on the other hand, has excellent quantum yield apart from intracellular fluorophores, but there are no efficient quenchers that could be chemically linked to R6G. Herein, we show that R6G is able to form intermolecular FRET pairs with MUmb or AMC, with the latter serving as fluorescence donors. This yields a combination of R6G’s excellent fluorescence properties with a possibility to use an enzyme-sensitive linker in MUTMAC or AMC derivatives. This phenomenon was initially discovered in a model system, reversed micelles, where the donor, the acceptor, and the enzyme are forced to be in close proximity to each other, so that proximity could serve as an explanation for the intermolecular FRET effect. Surprisingly enough, the phenomenon has been reproduced in living cells. Moreover, we were able to create working intermolecular donor–acceptor FRET pairs for several different enzymes, including chymotrypsin, phosphatase, and asparaginase. This appears counterintuitive, as besides the overlap of the emission spectra of the donor and the absorption spectra of the acceptor, there are other criteria for the FRET effect, including the convergence of two fluorophores at a distance of about 1–10 nm, and the orientation of their dipoles at a certain angle, which is difficult to imagine in a bulk system like a living cell. We hypothesize that FRET-enabling donor–acceptor interaction may be taking place at the inner surface of the lipid bilayer, to which both donor and acceptor molecules would likely have an affinity. This hypothesis would require a more detailed investigation. Therefore, we have shown that the method suggested has good potential in the visualization of enzyme functioning inside living cells, which is often a challenging task. Shifting of the fluorescence signal to the long-wavelength region would increase the signal selectivity, making it easily distinguishable from autofluorescence.

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Influence of color fixation agent (CFA) and dyebath pH in secondary alcohol ethoxylate (SAE)-based reverse micellar dyeing system of cotton with reactive dyes was investigated and compared with water-based dyeing system using different alkali (i.e. CFA) such as: (i) sodium bicarbonate (NaHCO3), (ii) sodium carbonate (Na2CO3) and (iii) sodium hydroxide (NaOH). The color, tensile strength, fastness and surface morphological properties of dyed samples were examined. Experimental results showed that samples dyed with Na2CO3 can achieve the highest color yield, followed by NaHCO3 and NaOH in both water-based and reverse micellar dyeing system. The color yield and reflectance percentage of the dyed cotton samples were found to be closely related to the dyebath pH value. Relative unlevelness indices (RUI) also reflected that cotton samples dyed with NaOH in reverse micellar dyeing system have a higher chance of color unlevelness when compared with NaHCO3 and Na2CO3. Tensile strength results affirm that higher alkalinity of dyebath could cause higher strength loss to the colored cotton samples. Both cotton samples dyed by water and SAE approach showed good to excellent color fastness properties while scanning electron microscopic (SEM) images exhibit that the use of different alkalis may cause some damage to the cotton fiber.

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The oral absorption of exenatide, a type 2 diabetes medication, can be increased by employing lipid nanocapsules (LNC). To increase mucus permeability and exenatide intestinal absorption, reverse micelle lipid nanocapsules (RM-LNC) were prepared and their surface was modified with DSPE-PEG-FA. The RM-LNC with surface modification of DSPE-PEG-FA (FA-RM-LNC) were able to target enterocytes and reduce mucus aggregation in the intestine. Furthermore, in vitro absorption at different intestinal sites and flip-flop intestinal loop experiments revealed that LNCs with surface modification significantly increased their absorption efficiency in the small intestine. FA-RM-LNC delivers more drugs into Caco-2 cells via caveolin-, macrophagocytosis-, and lipid raft-mediated endocytosis. Additionally, the enhanced transport capacity of FA-RM-LNC was observed in a study of monolayer transport in Caco-2 cells. The oral administration of exenatide FA-RM-LNC resulted in a prolonged duration of hypoglycemia in diabetic mice and a relative bioavailability (BR) of up to 7.5% in rats. In conclusion, FA-RM-LNC can target enterocytes and has promising potential as a nanocarrier for the oral delivery of peptides. [ABSTRACT FROM AUTHOR]

In this paper, the swelling effect of ionic liquid reverse micelle system on cotton fabric in supercritical CO2, and the influence of swelling on the dyeing of cotton fabric were studied. The results indicate that the ionic liquid reverse micelle system can cause swelling of cotton fabric. In the process of alkali free dyeing, swelling has a significant effect on the dyeing properties of cotton. With the extension of reaction time, both the crystallinity and XRD diffraction intensity of cotton fabric decreased, and the dyeing depth (K/S value) of cotton fabric increased. The temperature and molar ratio of ionic liquid to surfactant have a significant impact on the swelling of cotton fabrics. At higher temperature (90 °C), the crystallinity index of cellulose in cotton fabric significantly decreases, which affected the K/S values of dyed cotton fabric. Adding a certain amount of DMSO can promote the swelling of cotton fiber, greatly reduce crystallinity, and improve the dyeing performance of cotton fabric. [ABSTRACT FROM AUTHOR]

Feasibility and applicability of rhamnolipid (RL) microbial biosurfactant-based reverse micellar non-aqueous system in different solvent medium for dyeing of cotton fabrics was investigated. In this study, several solvents, including heptane, octane, nonane, decamethylcyclopentasiloxane (D5), and paraffin liquid (PL), were chosen as the dyeing medium for non-aqueous dyeing of cotton fabrics with fixed dyeing parameters. The dyeing properties of these RL reverse micellar dyed samples in different solvent medium were examined and compared with the conventional water-dyed samples in terms of color yield (K/Ssum value), CIE L*a*b* values, color levelness and reflectance. Most non-aqueous RL reverse micellar dyed samples exhibited better color yield than conventional water-dyed samples. The surface morphology of dyed cotton samples and the dye encapsulation morphology in different solvent medium were observed by SEM and TEM, respectively. Most non-aqueous dyed samples yielded good to excellent levelness comparable to water-dyed samples. However, poor levelness and bad levelness were found for D5-and PL-dyed samples. Further modification of dyeing parameters would be needed to obtain the best dyeing results for D5-dyed and PL-dyed samples. [ABSTRACT FROM AUTHOR]

AbstractThe oral absorption of exenatide, a type 2 diabetes medication, can be increased by employing lipid nanocapsules (LNC). To increase mucus permeability and exenatide intestinal absorption, reverse micelle lipid nanocapsules (RM-LNC) were prepared and their surface was modified with DSPE-PEG-FA. The RM-LNC with surface modification of DSPE-PEG-FA (FA-RM-LNC) were able to target enterocytes and reduce mucus aggregation in the intestine. Furthermore, in vitro absorption at different intestinal sites and flip-flop intestinal loop experiments revealed that LNCs with surface modification significantly increased their absorption efficiency in the small intestine. FA-RM-LNC delivers more drugs into Caco-2 cells via caveolin-, macrophagocytosis-, and lipid raft-mediated endocytosis. Additionally, the enhanced transport capacity of FA-RM-LNC was observed in a study of monolayer transport in Caco-2 cells. The oral administration of exenatide FA-RM-LNC resulted in a prolonged duration of hypoglycemia in diabetic mice and a relative bioavailability (BR) of up to 7.5% in rats. In conclusion, FA-RM-LNC can target enterocytes and has promising potential as a nanocarrier for the oral delivery of peptides.

Glutathione is an antioxidant composed of cysteine containing -SH functional groups. Its concentration decreases with age, causing aging symptoms. Gluthathione has hydrophilic properties with a log P of -1.4, which requires a reverse micelle system by adding surfactants such as Tween 80 and Span 80 to adjusts the log P to 2-3 to aid the penetration of stratum corneum for dermal delivery. Anti-aging strategies involve cosmetics including peel-off masks, which require effective polymer for ease of application. This study combines polyvinyl alcohol (15,16,17%) and hidroxypropyl methylcellulose (3,4,5%) to create a suitable gel base for glutathione peel-off masks. This research aims to determine the influence of the PVA and HPMC combination as a base for glutathione peel-off masks in terms of real-time physical stability and irritation effects using the HET-CAM method. The glutathione preparation utilized the reverse micelle method, followed by the formulation of the peel-off mask with a base comprising an equivalent of 2% reverse micelle glutathione. The quality of the combination was assessed for stability, including organoleptic properties, pH, viscosity, spreading ability, and drying time. The HET-CAM irritation score was utilized for irritation testing. This study found that the concentration of gelling agents PVA and HPMC affects the physical stability (organoleptic, pH, drying time, spreading ability, and viscosity) of the glutathione peel-off mask. Additionally, the HET-CAM irritation test demonstrates that all three dosage forms (F1, F2, and F3) exhibit non-irritating characteristics, with scores within the non-irritating range of 0.0 to 0. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of using biodegradable secondary alcohol ethoxylate (SAE) non-ionic surfactant as a building block for the formation of reverse micelles, functioning as reactive dye carriers for the dyeing of cotton fabric in non-aqueous octane medium. Ten dyeing parameters were optimised, by a one-factor-at-a-time approach, namely: (i) effect of colour fixation agent; (ii) surfactant-to-water mole ratio; (iii) surfactant-to-co-surfactant mole ratio; (iv) volume of soda ash; (v) volume of dye; (vi) solvent-to-cotton ratio; (vii) dyeing temperature; (viii) dyeing time; (ix) fixation time; (x) soda-ash-to-cotton ratio. The colour properties, fastness properties and physical properties of SAE-dyed samples were experimentally compared with the conventional water-dyed samples. The optimised condition was found when SAE samples were dyed as follows: (a) 1:20 surfactant-to-water ratio; (b) 1:8 surfactant-to-co-surfactant ratio; (c) 10:1 solvent ratio; (d) 40 min dyeing time; (e) 60 min fixation time; and (f) 70 °C dyeing and fixation temperature. The results showed that SAE-dyed samples have better colour strength, lower reflectance percentage and comparable levelness, fastness and physical properties than that of water-dyed samples. SEM images revealed that the dyed cotton fibres had no severe surface damage caused by an SAE-based reverse micellar dyeing system. The TEM image depicts that the reverse micelle was of nanoscale, spherical-shaped and had a core–shell structure, validating the presence of reverse micelle as a reactive dye carrier and the potential of an SAE-based reverse micellar system for dyeing of cotton fabrics. [ABSTRACT FROM AUTHOR]

Orally administered peptides or proteins are garnering increasing preference owing to their superiority in terms of patient compliance and convenience. However, the development of oral protein formulations has stalled due to the low bioavailability of macromolecules that encounter the aggressive gastrointestinal environment and harsh mucus villi barrier. Herein, we propose an ideal reverse micelle/self-emulsifying drug delivery system (RM/SEDDS) nanoplatform that is capable of improving the oral bioavailability of hydrophilic peptides by preventing enzymatic degradation and enhancing mucosal permeability. Upon the passage through the mucus, the self-emulsifying drug delivery system with optimal surface properties effectively penetrates the viscoelastic mucosal barrier, followed by the exposure of the inner reverse micelle amphipathic vectors, which autonomously form continua with the lipidic cell membrane and facilitate the internalization of drugs. This membrane-fusion mechanism inaugurates a new way for hydrophilic peptide delivery in the free form, circumventing the traditional impediments of the cellular internalization of nanocarriers and subsequent poor release of drugs. And more importantly, reverse micelles are not spatially specific to the laden drugs, which enables their delivery for a myriad of peptide clinical drugs. In conclusion, as an exquisitely designed nanoplatform, RM/SEDDS overcomes multiple physiological barriers and opens a new path for drug cellular entry, providing new prospects for the development of oral drug delivery systems. [ABSTRACT FROM AUTHOR]

Reactive dyes of three primary colours used for exhaustion dyeing of cotton fabric in conventional water dyeing system and APG-based reverse micelle dyeing system, with D5 and alkane solvents as dyeing medium, were investigated. Calibration curves of both systems were established. Absorbance and dye concentration were found to be directly correlated with each other. The curves exhibited high linearity with R2 above 0.99, validating their suitability for subsequent SERF measurement. The values of substantivity factor (S), exhaustion factor (E), rate of fixation (R) and fixation factor (F) were measured and calculated in percentage. The results revealed that APG reverse micellar dyeing system obtains higher S and E, but lower R and F values than the conventional water dyeing system, verifying excellent final dye exhaustion and good leveling properties of the APG reverse micellar dyeing system when compared with the conventional aqueous dyeing system. The use of D5 and alkane solvents as dyeing medium causes no significant effect on the establishment of SERF profile in APG reverse micellar dyeing system. [ABSTRACT FROM AUTHOR]

Butyl oleate synthesis by the lipase B from Candida antarctica (CalB) under extreme halophilic conditions was investigated in the present research through the AOT/Water/Isooctane reverse micellar system. The impact of aqueous content ( W o = H 2 O S u r f a c t a n t ) and NaCl variation on the enzymatic activity of CalB in the butyl oleate reaction in reverse micelles was explored. The results indicated that, based on the increase of NaCl, it is remarkable to achieve higher enzymatic activity up to 444.85 μ mol min at 5 M NaCl and Wo = 10, as the best esterification conditions at pH 7.2 and 30 °C. However, it was clear that butyl oleate synthesis by lipase CalB increased based on the reduction in the average reverse micelle size, where reverse micelle sizes were determined by dynamic light scattering (DLS). This increase in butyl oleate synthesis demonstrated the potential of reverse micelles as systems that enhance mass transport phenomena in heterogeneous biocatalysis. Furthermore, reverse micelles are promising systems for extreme halophilic lipases research. [ABSTRACT FROM AUTHOR]

In order to realize the anhydrous dyeing of linen fabric with reactive dyes in supercritical CO2, a supercritical CO2 ionic liquid reverse micelle system was constructed, and the dyeing process of linen fabric in this system was studied. In this system, linen fabric can be dyed with reactive dyes without special pretreatment. The results show that the dyeing depth of linen fabric can be significantly improved by increasing the amount of surfactant. With the increase in temperature, the dyeing depth first increases and then decreases. The dyeing pressure displays little effect on the dyeing depth. After dyeing, there are a lot of floating colors on the surface of the fabric. Increasing the temperature and prolonging the dyeing time are conducive to dye fixation on the fabric. Adding a certain amount of dimethyl sulfoxide (DMSO) to the system can improve the dyeing performance significantly. In this paper, the best dyeing conditions of linen fabric are as follows: w, 1.2; surfactant conc. 3.5 × 10−2 g/mL; T, 90°C; t, 180 min; p, 21MPa; DMSO concentration, 76.8 mmol/L.

This work aims to examine the feasibility of using poly(ethylene glycol) (PEG)-based reverse micellar dyeing system for dyeing cotton fabric with the use of hot type trichloropyrimidine (TCP)-based reactive dyes and to evaluate the possibility of saving the dyeing energy used during the dyeing process. Experimental results show that fabrics dyed in reverse micellar system at 90°C can achieve higher color yield than the conventional water-based system at the same temperature. Further experiments using reverse micellar system for dyeing cotton at 80°C (a reduction of working temperature of 10°C) provided color yield comparable to that of conventional water-based system except the use of yellow dye. Both water-dyed and octane-dyed samples had good to excellent levelness, washing and rubbing fastness and 98.5% of octane could be recycled after distillation. Reflectance curves were identical in shape and the SEM images showed neither of the dyeing systems caused any significant damage to cotton fibers. These findings validated the possibility of using reverse micellar dyeing system for hot type TCP-based reactive dyeing of cotton fabrics at lower coloration temperature and energy consumption.

Reverse micellar dyeing of cotton woven fabrics with natural and biodegradable alkyl polyglucoside-based (APG-based) nonionic surfactant in decamethylcyclopentasiloxane (D5) non-aqueous medium with reactive dyes of different functional groups was investigated and compared with conventional aqueous water-based dyeing in terms of reflectance, color yield, levelness, CIE L*a*b* values, washing fastness and color fading properties. Experimental results have revealed that APG reverse micellar method can provide a higher color yield (K/Ssum value) and lower color reflectance (better dye uptake) than conventional water-based method, along with comparable washing fastness, leveling and color fading properties. Hetero-bifunctional reactive dyes can attain the highest color yield, followed by homo-bifunctional reactive dyes and mono-functional reactive dyes. Mono-functional reactive dyes and homo-bifunctional reactive dyes produce the best levelling properties with smallest levelness variation when compared with that of hetero-bifunctional reactive dyes in non-aqueous D5 dyeing medium.

The feasibility of computer colour matching (CCM) of rhamnolipid-based reverse micellar dyeing system on cotton fibre in octane media has been investigated and compared with that of conventional water-based dyeing system. Calibration results confirm that the calibration curves of both systems are linear in structure. Reflectance curves reveal that both water-dyed and RL octane-dyed standard and batch samples are identical in shape without any peak shift and alteration of colour properties. The actual colour matching results of RL octane reverse micellar dyeing system are close to theoretical prediction with percentage difference less than 25%, verifying the applicability of CCM on RL reverse micellar dyeing system. RL octane-dyed samples can achieve good to excellent levelness, washing and rubbing fastness, which are comparable to that of water-dyed samples. Further experiments have been conducted to analyse the zeta-potential surface charge, particle size distribution and Raman spectra of RL. Volatile organic compound (VOC) detection and solvent recovery have also been conducted. Experimental results reveal that the leakage of octane solvent is between 2 and 3 ppm which is at acceptably low level whilst more than 98% of octane can be recovered for further use after the RL reverse micellar dyeing process, validating the environmental friendliness potential of the RL octane reverse micellar dyeing system. [ABSTRACT FROM AUTHOR]

In order to realize the anhydrous dyeing of linen fabric with reactive dyes in supercritical CO2, a supercritical CO2 ionic liquid reverse micelle system was constructed, and the dyeing process of linen fabric in this system was studied. In this system, linen fabric can be dyed with reactive dyes without special pretreatment. The results show that the dyeing depth of linen fabric can be significantly improved by increasing the amount of surfactant. With the increase in temperature, the dyeing depth first increases and then decreases. The dyeing pressure displays little effect on the dyeing depth. After dyeing, there are a lot of floating colors on the surface of the fabric. Increasing the temperature and prolonging the dyeing time are conducive to dye fixation on the fabric. Adding a certain amount of dimethyl sulfoxide (DMSO) to the system can improve the dyeing performance significantly. In this paper, the best dyeing conditions of linen fabric are as follows: w, 1.2; surfactant conc. 3.5 × 10−2 g/mL; T, 90°C; t, 180 min; p, 21MPa; DMSO concentration, 76.8 mmol/L. [ABSTRACT FROM AUTHOR]

Pluronics are a family of amphiphilic block copolymers broadly explored in the pharmaceutical field. Under certain conditions, Pluronics self-assemble in different structures including nanosized direct and reverse micelles. This review provides an overview about the main parameters affecting the micellization process of Pluronics, such as polymer length, fragments distribution within the chain, solvents, additives and loading of cargo. Furthermore, it offers a guide about the most common techniques used to characterize the structure and properties of the micelles. Finally, it presents up-to-date approaches to improve the stability and drug loading of Pluronic micelles. Special attention is paid to reverse Pluronics and reverse micelles, currently underexplored in the literature. Pluronic micelles present a bright future as drug delivery agents. A smart design and thorough characterization will improve the transfer to clinical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co(OH) 2 synthesised in reverse micellar core of SPAN 80/1-butanol/water/toluene. • O/W Pickering emulsion is developed by Co(OH) 2 , in situ hydrophobized with SDS. • An ambiguous phase separation of Pickering emulsion is noticed at 4.3 mM SDS. • Hydrophobic interaction through tail-to-tail mode leads nanoplates-like architect. • Hydrophilic surface from both ends result to loss of amphiphilic character. The present study employs reverse micellar-templated Co(OH) 2 nanospheres, in situ hydrophobized with SDS in Pickering emulsion formulations and unlocking the mechanism of ambiguous phase separation at a certain surfactant concentration (4.3 mM). Co(OH) 2 is synthesised in the core of reverse micelle: SPAN 80/1-butanol/water/toluene. Novel O/W Pickering emulsions have been developed with the help of positively charged (ς = 4.47 mV) Co(OH) 2 (0.05 wt%) and an adequate amount of an anionic surfactant, SDS. An ambiguous phase separation of Pickering emulsion at 4.3 mM SDS is noticed within just 4 hr of standings, whereas, surprisingly stable O/W Pickering emulsions are found above and below these SDS concentrations. Upon addition of 2.6 mM SDS to the aqueous colloidal dispersion of Co(OH) 2 , the particles converted to amphiphilic one and stabilized the Pickering emulsion. However, these monolayer adsorbed surfactants face a hydrophobic interaction through tail-to-tail mode after adding 4.3 mM SDS to the colloidal dispersion. Consequently, they achieve a nanoplates-like architect and regain the extreme hydrophilic surface from both ends and eventually leads to the ambiguous phase separation through inter-droplet coalescence. The contact angle value altering from 44.9° (for 2.6 mM SDS) to 19.6° (for 4.3 mM SDS) confirms that the surface has changed from being amphiphilic to becoming extremely hydrophilic. Yet, again an increase in SDS (6.06 mM and onwards) suggest that surfactant molecules further adsorbed in either any of the two hydrophilic ends and revolving the particles to its previous amphiphilic state and eventually started to stabilise the emulsion droplets. [ABSTRACT FROM AUTHOR]

• The protic ionic liquid-surfactant imim-AOT was synthesized and characterized. • Imim-AOT forms reverse micelles in biocompatible non-polar solvents, encapsulating water. • The reverse micelles were characterized by DLS, FT-IR and 1H NMR. • Imim-AOT systems showed strong imim+-water interactions through the N H of imim+. • Surfactant conformation dictates interfacial properties over non-polar solvent type. The synthesis and characterization of a novel surfactant derived from AOT, 1-methylimidazolium 1,4-bis-2-ethylhexylsulfosuccinate (imim-AOT), were conducted, revealing its unique ionic liquid properties. Imim-AOT forms reverse micelles (RMs) in biocompatible solvents methyl laurate (ML) and isopropyl myristate (IPM) without the need for a cosurfactant, and its performance was compared with that of the traditional surfactant Na-AOT. Dynamic light scattering studies demonstrated the ability of imim-AOT to solubilize water, forming non-interacting spherical systems. Fourier-transform infrared (FT-IR) spectroscopy and proton nuclear magnetic resonance (1H NMR) spectroscopy revealed that replacing Na+ with imim+ alters the micellar interface properties. Imim-AOT systems showed weaker water-AOT interactions compared to Na-AOT RMs, attributed to the strong imim+-water interactions through the N H group of the imidazolium cation. Importantly, no significant differences were observed between micellar systems in IPM and ML, indicating that surfactant conformation dictates interfacial properties rather than the external solvent type. These findings highlight the potential of imim-AOT in nanoreactor applications and underscore its suitability for environmentally benign micellar systems with potential applications in nanomedicine. In summary, our research provides interesting insights into the behavior of protic ionic liquid-surfactant in forming reverse micelles, offering a compelling comparison with traditional surfactants. Our findings demonstrate that the protic ionic liquid-surfactant not only efficiently forms reverse micelles but also exhibits good performance in terms of stability and solubilization capabilities. [ABSTRACT FROM AUTHOR]

This paper describes an alternative method for the in situ synthesis of gold nanoparticles (AuNPs) with a particle size of less than 3 nm, using nanoreactors formed by reverse micelles of 1,4-bis-(2-ethylhexyl) sulfosuccinate sodium (AOT) and nanoparticle stabilization with l -cysteine, which favor the preparation of nanoparticles with size and shape control, which are homogeneously dispersed (1% by weight) on the support of titanium dioxide nanowires (TNWs). To study the activity and selectivity of the prepared catalyst (AuNPs@TNWs), an aqueous solution of 40 mM glycerol was irradiated with a green laser (λ = 530 nm, power = 100 mW) in the presence of the catalyst and O 2 as an oxidant at 22 °C for 6 h, obtaining a glycerol conversion of 86% with a selectivity towards hydroxypyruvic acid (HA) of more than 90%. From the control and reactions, we concluded that the Ti–OH groups promote the glycerol adsorption on the nanowires surface and the surface plasmon of the gold nanoparticles favors the selectivity of the reaction towards the hydroxypyruvic acid. [Display omitted] • The reverse micelle method allows the deposition of small Au NPs nanoparticles. • Reactive –OH groups on H 2 Ti 3 O 7 nanowires surface allow the adsorption of glycerol. • The Au NPs absorb visible green light. • AuNPs@HTNWs and AuNPs@TNWs allow the activation of O 2 via formation of O 2.•-. • Hydroxypyruvic acid was obtained as the main product in glycerol oxidation. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of using biodegradable secondary alcohol ethoxylate (SAE) non-ionic surfactant as a building block for the formation of reverse micelles, functioning as reactive dye carriers for the dyeing of cotton fabric in non-aqueous octane medium. Ten dyeing parameters were optimised, by a one-factor-at-a-time approach, namely: (i) effect of colour fixation agent; (ii) surfactant-to-water mole ratio; (iii) surfactant-to-co-surfactant mole ratio; (iv) volume of soda ash; (v) volume of dye; (vi) solvent-to-cotton ratio; (vii) dyeing temperature; (viii) dyeing time; (ix) fixation time; (x) soda-ash-to-cotton ratio. The colour properties, fastness properties and physical properties of SAE-dyed samples were experimentally compared with the conventional water-dyed samples. The optimised condition was found when SAE samples were dyed as follows: (a) 1:20 surfactant-to-water ratio; (b) 1:8 surfactant-to-co-surfactant ratio; (c) 10:1 solvent ratio; (d) 40 min dyeing time; (e) 60 min fixation time; and (f) 70 °C dyeing and fixation temperature. The results showed that SAE-dyed samples have better colour strength, lower reflectance percentage and comparable levelness, fastness and physical properties than that of water-dyed samples. SEM images revealed that the dyed cotton fibres had no severe surface damage caused by an SAE-based reverse micellar dyeing system. The TEM image depicts that the reverse micelle was of nanoscale, spherical-shaped and had a core–shell structure, validating the presence of reverse micelle as a reactive dye carrier and the potential of an SAE-based reverse micellar system for dyeing of cotton fabrics.

Malachite green (MG) is a dye that has been presented to use as photosensitizers for photodynamic therapy (PDT). Nonlinear absorption coefficient (β) and nonlinear refractive index (n2) of MG formulations with micelles and its encapsulation are studied aiming PDT. Encapsulation of MG was prepared by the mixture of water droplet in the continuous phase of oil, stabilized with surfactant. MG interacts with micelles and reverses micelle (RM), and the results are related to the size and concentration of micelles, RM, surfactant charge types. At low capsule size, the 1/β linearly increases by the increase of volume fraction of water droplet, while, an exponential behavior was observed in the higher capsule size. [ABSTRACT FROM AUTHOR]

A gel with mucoadhesive properties and a controlled release profile is a suitable dosage form for reverse micellar EGCG delivery. In this study, ĸ-Carrageenan and HPMC K100M were used as the gel components at a weight ratio of 1:1.5, respectively, for loading native and reverse micellar EGCG. The characteristics of the gel were determined based on pH, swelling index, disintegration time, hardness, and entrapment efficiency. The in vitro EGCG release rate was further determined for EGCG levels. Moreover, in vivo cervical penetration studies of rhodamine-labeled EGCG gels in mice at two and six hours after intravaginal administrations were conducted. The results showed that the pH and hardness characteristics of the gels for each formula did not differ significantly, while the gel-loaded reverse micellar EGCG had a higher swelling index than that of native EGCG gels. In addition, the rate of release and cervical penetration of rhodamine-labeled reverse micellar EGCG loaded in gels was higher than those of rhodamine-labeled native EGCG gels. Therefore, it can be concluded that loading reverse micelles EGCG into gels prepared with ĸ- Carrageenan and HPMC K100M successfully controlled the release rate and improved cervical penetration, thereby enabling its potential use in cervical cancer treatment. [ABSTRACT FROM AUTHOR]

Reverse micelles (RMs) are spontaneously organizing nanobubbles composed of an organic solvent, surfactants, and an aqueous phase that can encapsulate biological macromolecules for various biophysical studies. Unlike other RM systems, the 1-decanoyl- rac -glycerol (10MAG) and lauryldimethylamine-N-oxide (LDAO) surfactant system has proven to house proteins with higher stability than other RM mixtures with little sensitivity to the water loading (W 0 , defined by the ratio of water to surfactant). We investigated this unique property by encapsulating three model proteins – cytochrome c , myoglobin, and flavodoxin – in 10MAG/LDAO RMs and applying a variety of experimental methods to characterize this system's behavior. We found that this surfactant system differs greatly from the traditional, spherical, monodisperse RM population model. 10MAG/LDAO RMs were discovered to be oblate ellipsoids at all conditions, and as W 0 was increased, surfactants redistributed to form a greater number of increasingly spherical ellipsoidal particles with pools of more bulk-like water. Proteins distinctively influence the thermodynamics of the mixture, encapsulating at their optimal RM size and driving protein-free RM sizes to scale accordingly. These findings inform the future development of similarly malleable encapsulation systems and build a foundation for application of 10MAG/LDAO RMs to analyze biological and chemical processes under nanoscale confinement. [Display omitted] • 10MAG/LDAO RMs form ellipsoids that become more spherical with added water. • Proteins in 10MAG/LDAO RMs modify the particle size distribution to accommodate the native state. • The 10MAG/LDAO RM system is instructive for development of versatile systems for protein encapsulation. [ABSTRACT FROM AUTHOR]

The size and uniformity of magnetic nanoparticles are essential for biomedical performance. In this study, we successfully controlled the size and uniformity of magnetic nanomaterials by applying gradient magnetic fields during the solvothermal method. This regulation method conforms to the following laws: the size of the synthesized magnetic nanoparticles (MNPs) is smaller when the applied magnetic field is stronger, and the synthesized uniformity is better when the product of the applied field and its gradient is greater. In vitro and in vivo magnetic resonance imaging experiments show that magnetic field treatment resulted in uniform MNPs of 4.5 nm, which can significantly improve the T1 contrast performance. We further propose a dynamic process of field-induced reconfiguration for reverse micelles (re-micelles) to analyze how the gradient magnetic field affects MNP synthesis. [ABSTRACT FROM AUTHOR]

Amine modified nano-silica was prepared via a one-pot route and under very mild conditions in water in oil microemulsion with a non-ionic surfactant to study the effect of changing the amount of N-[3-(Trimethoxysilyl)propyl]ethylenediamine (DA) added to the synthesis mixture on the characteristics of the obtained nanocomposite such as morphology, crystallinity, surface charge, particle size, surface area, and accordingly the effect of all of these factors on the efficiency of the nanocomposite for the removal of heavy metal ions, namely zinc, from aqueous solutions. XRD, SEM, TGA, BET, DLS, FTIR, and pH0 analysis were performed for samples and the results showed a strong effect for the amount of DA added to the synthesis mixture on the characteristics of the obtained nanocomposites. It was found that increasing the amount of DA added to the synthesis mixture increased the pH0, hydrodynamic particle size obtained by dynamic light scattering analysis, and the particle size obtained by SEM. Sample prepared without the addition of DA (SNP) and the samples prepared with 1.5 mL of DA (SNP-1.5DA) showed a better adsorption performance compared to the samples prepared with 0.5 and 1.0 mL of DA (SNP-0.5DA and SNP-1.0DA, respectively). The main factor affecting the adsorption efficiency was found to be the available surface area for each nanocomposite, which was directly related to the degree of crystallinity as obtained by XRD analysis. [ABSTRACT FROM AUTHOR]

The degradation performance of Cu-TiO2 nanomaterials towards levofloxacin (LFX) antibiotic was investigated under an environmentally benign visible LED light source. Cu-TiO2 nanomaterials were prepared using the reverse micelle sol–gel method with different copper content ranging from 0.25 to 1.0 wt% concerning titania. Characterization of Cu-TiO2 samples was performed by XRD, TEM, UV–Vis, BET, ICP-MS, FTIR and XPS techniques. 0.5 wt% Cu-TiO2 showed crystallite size below 6 nm, surface area (69.85 m2/g) and significant visible light absorption capacity. Both Cu1+ and Cu2+ are formed in lower Cu-doped TiO2 samples, whereas only Cu2+ is present in higher Cu-doped TiO2 samples as evident in XPS analysis. 0.5 wt% Cu-TiO2 has shown the optimum photocatalytic degradation of 75.5% under 6 h. of a visible light source. FTIR analysis of LFX adsorbed Cu-TiO2 materials indicated the pollutant–catalyst interaction, where the declining trend was observed in photocatalytic degradation efficiency for higher Cu-doped TiO2 samples due to copper-LFX complex formation. Copper-LFX complexes are formed due to the presence of Cu2+ in higher Cu-doped TiO2 nanomaterials, which might have hindered the photocatalytic activity under visible light. Effects of initial pollutant concentration, catalyst loading and visible light intensity on the degradation of LFX are studied. Photocatalytic degradation pathways of LFX using best performing Cu-TiO2 material were also proposed based on the LC–MS analysis. [ABSTRACT FROM AUTHOR]

The dyeing and color fixation properties of reactive dyes on cotton woven fabrics have been systematically studied using reverse micelle with biodegradable alkyl polyglucoside (APG)-based non-ionic surfactant as building blocks in cyclosiloxane-based solvent under one-bath one-step approach. Reactive dyes were solubilized in the interior region of the reverse micelle under optimized process conditions as indicated by the color strength. Assessment of the color strength and fastness properties of cotton fabrics in reverse micellar dyeing was conducted and compared with aqueous dyeing. It was found that fluoropyrimidine reactive group of Levafix CA Red dyes encapsulated in APG-based reverse micelle exhibited higher color yield on cotton fabric compared to vinylsulfone group of both Levafix CA yellow and blue dyes. The results also represent that reactivity of the functional group combination of heterofunctional dyes influences color fixation on cellulosic surface in terms of color strength (K/S sum). [ABSTRACT FROM AUTHOR]

Gallic acid and phloroglucinol are the main phenolic compounds of the pistachio green hull (Pistachia vera) extract. The anti-radical and -peroxide activities of gallic acid and phloroglucinol were compared through DPPH radicals scavenging, bleaching of β-carotene (BCB), and Rancimat assays. The gallic acid molecules (log P = − 0.46) with an electron-donating carboxylate anion had significantly higher radical scavenging activities than phloroglucinol molecules (log P = 1.38) in DPPH (IC50 = 30.53 vs. 45.72 μM), BCB (IC50 = 43.66 vs. 66.15 μM), and Rancimat (OSI = 4.89 vs. 2.26 h) assays. The combinational kinetic model was successfully used for the determination of kinetic parameters, such as induction period (IP), the maximum concentration of lipid hydroperoxides (PVmax), and critical reverse micelle concentration (CMC) in soybean oil triacylglycerols (TAGs) peroxidized at 60 °C. The kinetics parameters, antioxidant effectiveness (F), and activity (AA) revealed gallic acid had the highest inhibitory effect during TAGs peroxidation due to the improved interfacial performance. Gallic acid and phloroglucinol were able to protect TAGs against peroxidation (IP = 388.34–816.21 vs. 25.53–122.4 h) in terms of the extent of their participation in the main reaction of chain termination and pro-oxidative side reactions of chain initiation, and anti-oxidative side reactions of chain propagation. [ABSTRACT FROM AUTHOR]

We demonstrated the synthesis of spherical nanostructured g-Al2O3 using reverse micelle templating to enhance the surface area and reactant accessibility. Three different surfactants were used in this study: benzalkonium chloride (BZK), sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB). We obtained spherical nanostructured particles only using CTAB that form a reverse micelle emulsion. The particles have wide size distribution with an average size of 2.54 mm. The spherical particles consist of nanoplate crystallites with size 20-40 nm randomly arranged forming intercrystallite spaces. The crystalline phase of as-synthesized and calcined particles was boehmite and g-Al2O3, respectively as determined by XRD analysis. Here, the preserved particle morphology during boehmite to g-Al2O3 transformation opens a facile route to synthesize g-Al2O3 particles with complex morphology. The specific surface area of synthesized particles is 201 m2/g, which is around five times higher than the conventional g-Al2O3 (Aldrich 544833). Spherical nanostructured g-Al2O3 provides wide potential applications in catalysis due to its high density closed packed structure, large surface area, and high accessibility.

A simple supramolecular dispersive liquid‐liquid microextraction‐solidified floating organic drop (SMDLLME‐SFOD) method was developed for the separation and preconcentration of brilliant green (BG) before its spectrophotometric determination. The method is based on the extraction of ion‐pair of BG with sodium dodecyl sulfate into the coacervates made up of decanoic acid reverse micelles in the tetrahydrofuran‐water mixture. The influence of the effective parameters on the extraction of BG was investigated and optimized using response surface methodology. Under the optimized conditions, the calibration graph was linear in the range of 1.0–50.0 μg L−1 of BG. The limit of detection (LOD) and limit of quantification (LOQ) were 0.28 μg L−1 and 0.94 μg L−1, respectively. The repeatability expressed as the relative standard deviation for six replicate measurements at 5.0 μg L−1 BG was 3.6%. The method was successfully applied to the extraction and determination of BG in different water and fish samples. [ABSTRACT FROM AUTHOR]

We have demonstrated a unique approach to alter the aqueous pool size of an AOT/n-heptane/water reverse micellar system. A positively charged dye Rhodamine B (RhB) and negatively charged Rose Bengal (RB) were incorporated in the reverse micellar pool to investigate the effect of electrostatic interactions and stacking effects among the dye molecules on the AOT/n-heptane/water interface. Dynamic light scattering revealed increase in reverse micellar pool size in presence of positively charged dye aggregates at the oil–water interface. However, less expansion was observed in presence of negatively charged dye aggregates (RB). This confirms the role of electrostatic interaction in modulating the hydrodynamic radius. A head-to-tail type of stacking of RhB molecules at the interface favors this expansion. The differences in stacking of the two dyes inside the reverse micelles and their torsional mobility indicated the role of the reverse micellar interface and H-bonding ability of the microenvironment on dye aggregation. Conductivity measurements demonstrated a significant drop in percolation temperature of the reverse micellar system in presence of dye aggregates. This confirms the effect of dye aggregation and electrostatic interaction on such expansion. This strategy can be exploited for solubilizing greater amounts and a wider variety of drug molecules in microemulsions. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the forward and backward extraction efficiency, structure, and emulsifying properties of soybean proteins obtained through bis (2‐ethylhexyl) sulfosuccinate sodium salt (AOT) reverse micelle, as well as their relationship. The results showed that the extraction efficiency was the highest with the forward extraction time of 25 min, pH of 3.0, temperature of 45°C, KCl concentration of 0.0 mol L−1, and the backward extraction time of 10 min, pH of 4.0, temperature of 30°C, KCl concentration of 0.5 mol L−1. Significant changes in the secondary structure and fluorescence intensity of soybean protein after AOT reverse micelle extraction were observed. More β‐sheet structure and higher fluorescence intensity corresponded to the higher emulsion stability of soybean protein. The results indicated that reverse micelle extraction shows great application in food industry. [ABSTRACT FROM AUTHOR]

Pluronics are a family of amphiphilic block copolymers broadly explored in the pharmaceutical field. Under certain conditions, Pluronics self-assemble in different structures including nanosized direct and reverse micelles. This review provides an overview about the main parameters affecting the micellization process of Pluronics, such as polymer length, fragments distribution within the chain, solvents, additives and loading of cargo. Furthermore, it offers a guide about the most common techniques used to characterize the structure and properties of the micelles. Finally, it presents up-to-date approaches to improve the stability and drug loading of Pluronic micelles. Special attention is paid to reverse Pluronics and reverse micelles, currently underexplored in the literature. Pluronic micelles present a bright future as drug delivery agents. A smart design and thorough characterization will improve the transfer to clinical applications.

A reverse micellar floating solidification liquid-phase microextraction was proposed for simultaneous preconcentration and determination of both polar (scutellarin, baicalin) and non-polar (scutellarein, luteolin, apigenin, wogonin) quality-markers of flavonoids in traditional Chinese medicine coupled with high performance liquid chromatography-ultraviolet detection. In this work, the reverse micelle of Aliquat 336/dodecanol as the extractant was used to enrich target analytes. The synthesis of the reverse micellar extractant was investigated, and its microstructure was characterized by fluorescence microscope and transmission electron microscope. The variables affecting the experimental procedure, including reverse micelle volume, sample phase pH, salt amount, extraction temperature, extraction time and stirring rate were investigated and optimized. Under the optimum conditions, enrichment factors between 155 and 329 for the target analytes, satisfactory linear ranges (r ≥ 0.9983), low detection limits (0.05–0.25 ng mL−1), acceptable precisions (relative standard deviations of 0.2–8.9%) and accuracies (recoveries of 87.2–108.5%) were obtained. The extraction mechanism based on reverse micelle was explored and elucidated. The characteristics of the proposed method were summarized by comparison with others. The developed approach was successfully applied for the extraction and concentration of six quality-markers of flavonoids with different polarities from a traditional Chinese medicinal herb of Scutellariae Barbatae Herba. [ABSTRACT FROM AUTHOR]

Healthcare-acquired bacterial infections are a threat to public health. Therefore, development of self-sterilizing implantable dressing materials is in increasing demand. Herein, a series of quaternized triblock copolymers, namely, QP-b-PCL-b-QPs, are synthesized and self-assembled into reverse micelles (RMs) in tetrahydrofuran. The RMs contain biocompatible poly(ε-caprolactone) (PCL) blocks in the shell to render biosafety and responsiveness, and biocidal quaternary blocks in the core to render antibacterial activity. In the presence of bacterial lipase, the biodegradable PCL blocks are hydrolyzed, resulting in the responsive release of quaternary biocidal agents (QBAs) to enable self-sterilization. The RMs can be facilely impregnated into commercial gelatin sponge (GS) to fabricate RM2-coated GS, which impose potent antibacterial activity in the presence of lipase. Compared to Gram-negative P. aeruginosa, the Gram-positive S. aureus and B. subtilis are more susceptible to QBAs released from RM2-coated GS. The in vivo antibacterial assays and histological analyses further confirm the validity of RM2-coated GS in reducing bacterial infection in mice model. These results, taken together, provide a promising strategy for the development of bioswitchable self-sterilizing dressing materials to reduce healthcare-acquired bacterial infections. [ABSTRACT FROM AUTHOR]

The colour quality assessment of reverse micelle-based (in octane or nonane medium) and conventional water-based dyed wool knitted fabric has been investigated using computer colour matching (CCM) approach. Both water-based and non-aqueous based dyeing methods exhibited no chromatic shift from the reflectance curves and established good linearity in the construction of calibration curves. The linearity of both calibration curves in terms of R2 value played a critical role in CCM. The colour yield obtained from reverse micellar dyed fabric samples was higher than the colour yield values from wool knitted fabrics dyed in water bath under different dye percentages. The CCM predicted concentrations were in good agreement to theoretical concentrations for both dyeing systems. To conclude, the results showed that reverse micellar dyeing in octane and nonane is capable of generating reliable colour recipes. The relative unlevelness indices (RUI) obtained from dyed wool knitted fabrics using reverse micellar approach reveal good to excellent levelness, which fulfills the requirements of the textile processing industry. TEM picture illustrated that reverse micelles are in nano-scale and this could enhance the dyeing effect of wool with reactive dyes. [ABSTRACT FROM AUTHOR]

A supramolecular dispersive liquid−liquid microextraction method based on the solidification of the floating organic drop (SM-DLLME-SFOD) combined with spectrophotometry was developed for the separation, preconcentration, and determination of trace amounts of nickel from aqueous samples. The method is based on the extraction of the hydrophobic complex of nickel with α-furildioxime in the coacervates made up of undecanol reverse micelles in a water-tetrahydrofuran mixture. The parameters affecting the extraction of nickel were screened by fractional factorial design with central points. Effective experimental parameters were optimized using central composite design. Under the optimized conditions, the calibration graph was linear for nickel in the concentration range of 3–85 µg/L with a determination coefficient of 0.9992. The limit of detection and the enhancement factor of the method were 0.4 µg/L and 147, respectively. The method was successfully applied to the determination of nickel in water and vegetable samples. [ABSTRACT FROM AUTHOR]

Herein, we presented the synthesis and application of sodium dodecylbenzenesulfonate–based silver nanoparticles (termed as SDBS-AgNPs). The SDBS reverse micelles (RMs) in ethanol was used as nanoreactor for green AgNPs synthesis. The size, structure, and shape of SDBS-AgNPs were well distinct by UV/visible (UV/Vis), Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM) techniques. The SDBS-AgNPs were quite stable even at high temperature (80 °C), salt concentration (up to 300 μM), and wide pH range (2 to 12). Moreover, SDBS-AgNPs were found to be highly sensitive and selective colorimetric sensor for antihypertensive drug amlodipine (AML). The interaction of AML with SDBS-AgNPs resulted as a substantial increase in the absorbance and a prominent blue shift in wavelength from 426 to 400 nm. DLS results were further confirmed that the SDBS-AgNPs break into smaller sized particles. Similarly, FTIR results also verified the SDBS-AgNPs etching–based sensing of AML molecules due to the strong attraction by amine and carbonyl functional groups on the target drug. The proposed sensor exhibited linear response in the range of 0.001–200 μM (R2 = 0.9917) with limit of detection (LOD) and quantification (LOQ) of 0.161 and 0.49 μM, respectively. The probe remained selective against AML, even in the presence of equimolar interfering species (including other drugs and metal ions). Furthermore, findings proposed that the SDBS-AgNPs might be used as effective substitute to minimize infection severity by obstructing the biofilm formation against nosocomial and urinary tract infection (UTI) causing pathogens. [ABSTRACT FROM AUTHOR]

Reverse micellar solutions are thermodynamically stable systems in which surfactant molecules surround water droplets within a continuous organic phase. Among their many applications, they can be used for the synthesis of nanoparticles of controlled agglomeration. Here, we consider the role specific ion effects play in reverse micelle size reduction. Dynamic light scattering measurements and the Gouy-Chapman electrical double layer model were combined to study water/AOT/isooctane reverse micellar systems (w o = 10). Linear relationships between the solvodynamic diameter (D) of reverse micelles containing various concentrations of FeSO 4 , Mg(NO 3) 2 , CuCl 2 , Al(NO 3) 3 , Fe(NO 3) 3 , Y(NO 3) 3 , NaBH 4 , ZrOCl 2 , and NH 4 OH, and their calculated Debye screening lengths, κ−1, were observed with decreasing D and increasing salt concentration (c). By comparing the linear fits for reverse micelle size as a function of c −1/2, we determined the size can be described as a function of the Debye screening length, cation valency (z), and specific anion hydrated radius (r an), where D = 3.1 z κ−1 + b i , and b i is linearly related to r an. Our model accurately predicts reverse micelle sizes with the addition of monovalent, divalent, and trivalent salts for which the primary hydrolyzed cation species has a charge that is equal to the cation valency. [ABSTRACT FROM AUTHOR]

Amine modified nano-silica was prepared via a one-pot route and under very mild conditions in water in oil microemulsion with a non-ionic surfactant to study the effect of changing the amount of N-[3-(Trimethoxysilyl)propyl]ethylenediamine (DA) added to the synthesis mixture on the characteristics of the obtained nanocomposite such as morphology, crystallinity, surface charge, particle size, surface area, and accordingly the effect of all of these factors on the efficiency of the nanocomposite for the removal of heavy metal ions, namely zinc, from aqueous solutions. XRD, SEM, TGA, BET, DLS, FTIR, and pH0 analysis were performed for samples and the results showed a strong effect for the amount of DA added to the synthesis mixture on the characteristics of the obtained nanocomposites. It was found that increasing the amount of DA added to the synthesis mixture increased the pH0, hydrodynamic particle size obtained by dynamic light scattering analysis, and the particle size obtained by SEM. Sample prepared without the addition of DA (SNP) and the samples prepared with 1.5 mL of DA (SNP-1.5DA) showed a better adsorption performance compared to the samples prepared with 0.5 and 1.0 mL of DA (SNP-0.5DA and SNP-1.0DA, respectively). The main factor affecting the adsorption efficiency was found to be the available surface area for each nanocomposite, which was directly related to the degree of crystallinity as obtained by XRD analysis.

• Ultrafine and stable reverse micelle catalyst was effective for slurry phase hydrocracking of residue. • The effect of promoter metal was investigated for hydrotreating purpose. • different solvents, reaction temperatures and metal concentrations. • due to stable and narrow particle size distribution of reverse micelle catalysts. Ultrafine and stable slurry-phase hydrocracking catalysts were prepared by the reverse micelle (RM) method. The optimization of RM catalysts was carried out using different solvents, metal (molybdenum) concentrations, and reaction temperatures. The effect of cobalt as a promoter metal was also evaluated. For this preparation method, different solvents such as pentane, hexane, and diesel were used. Hydrocracking activities of the prepared catalysts were tested using vacuum residue (VR) that has a high concentration of impurities. The catalyst prepared by the RM method using diesel as the solvent shows very high hydrocracking activity of the vacuum residue. Coke formation at the end of the reaction by this catalyst is also very low compared with the other catalysts. The thermogravimetric analysis (TGA) results show that the catalyst prepared using diesel as solvent is thermally stable. With its high stability, the catalyst remains in an ultrafine dispersed phase at actual reaction conditions. These ultrafine catalyst particles form a layer in between the submicron mesophase, which is a precursor of coke. Therefore, coke formation is very low for this catalyst. Other two catalysts prepared using pentane and hexane solvents were found not to be stable at reaction conditions. In these, catalyst particles may agglomerate into big particles, which then act as nucleation sites for mesophase asphaltene, promoting coke formation instead of coke inhibition. The coke yield is also high at higher Mo concentrations in the catalyst. The results revealed that the RM method can be used effectively to prepare an ultrafine dispersed catalyst for residue hydrocracking. However, the use of a suitable solvent plays an important role in forming a stable dispersed and highly effective catalyst. [ABSTRACT FROM AUTHOR]