Microemulsion Formulation Research Articles

Study of Phase Separation and Reversibility in CO2-Responsive Superamphiphile Microemulsions.

Phase separation of microemulsions occupies a key position in many applications, such as oil recovery, nanomaterial synthesis, and chemical reactions. Achieving an intelligent response is crucial to microemulsion development and application. For this reason, in this study, CO2-responsive superamphiphilic molecules were developed as rapidly switchable oil-in-water microemulsions. These superhydrophilic molecules with linear structures were produced by electrostatic interaction of stearic acid and aminotrimethyltriazine COSM-1 in a 1:1 molar ratio. The introduction of n-butanol as a cosurfactant in the CO2-responsive microemulsion system resulted in the spontaneous formation of stable microemulsions. The effect of the addition of n-butanol on the carbon dioxide-responsive microemulsion system was investigated, and the optimum amount of n-butanol was determined by optimization. After exposure to CO2 for 30 s, the superhydrophilic molecules decomposed into inactive components at the interface, leading to a complete phase separation of the microemulsion into oil and water phases. The system was purged with N2 at 60 °C for 10 min to remove the CO2, and the phase separation system was transformed into a clear microemulsion, which was then evaluated for its properties. The rapid response and complete demulsification of these surface CNFS superamphiphiles to CO2 suggest that they have promising applications in product separation, microemulsion recovery, and enhanced crude oil recovery.

Development of synergistic antifungal in situ gel of miconazole nitrate loaded microemulsion as a novel approach to treat vaginal candidiasis

Limited solubility is the main cause of the low local availability of anti-candidiasis drug, miconazole nitrate (MN). The study’s objective was to develop and characterize microemulsion (ME) based temperature-triggered in situ gel of MN for intravaginal administration to enhance local availability and antifungal activity. The solubility of MN was initially studied in different oils, surfactants, and co-surfactants. Then, pseudo-ternary phase diagrams were constructed to select the best ratio of various components. The ME formulations were characterized by thermodynamic study, droplet size, polydispersity index (PDI), viscosity, and in-vitro antifungal mean inhibition zone (MIZ). Selected MEs were incorporated into different in situ gel bases using a combination of two thermosensitive polymers (poloxamer (PLX) 407 and 188), with 0.6% of hydroxypropyl methylcellulose (HPMC K4M) and gellan gum (GG) as mucoadhesive polymer. ME-based gels (MG) were investigated for gelation temperature, gelation time, viscosity, spreadability, mucoadhesive strength, in vitro release profile, and MIZ test. Furthermore, the optimum MG was assessed for in vivo animal irritation test and FESEM investigation. Tea tree oil, lavender oil, tween 80, and propylene glycol (PG) were chosen for ME preparation for the optimal formulation; formulation ME7 and ME10 were chosen. After incorporation of the selected formulation into a mixture of P407 and P188 (18:2% w/w) with 0.6% mucoadhesive polymer, the resultant MG formulation (MG1) revealed optimum gelation temperature (33 ± 0.01℃) and appropriate viscosity with enhanced sustained release (98%) and retention through sheep vaginal mucosa, MG1 exhibited a better MIZ compared to the 2% MN gel formulation and the marketed MN product, and no rabbit vagina irritation. In conclusion, the miconazole nitrate-loaded MG-based formula sustained the duration of action and better antifungal activity than the marketed miconazole nitrate formulation.

Advancements in the Transdermal Drug Delivery Systems Utilizing Microemulsion-based Gels.

Microemulsion gel, as a promising transdermal nanoparticle delivery system, addresses the limitations of microemulsions and enhances their performance in drug delivery and release. This article aims to discuss the advantages of microemulsion gel, including improved drug bioavailability, reduced drug irritation, enhanced drug penetration and skin adhesion, and increased antimicrobial properties. It explores the methods for selecting microemulsion formulations and the general processes of microemulsion preparation, as well as commonly used oil phases, surfactants, and co-surfactants. Additionally, the biomedical applications of microemulsion gel in treating conditions, such as acne and psoriasis, are also discussed. Overall, this article elucidates the significant potential of microemulsion gel in topical drug delivery, providing insights into future development and clinical applications.

Structure and Potential Application of Surfactant-Free Microemulsion Consisting of Heptanol, Ethanol and Water

Microemulsions, which are thermodynamically stable and isotropic mixtures of water, oil, and surfactants, attract significant research interest due to their unique physicochemical properties and diverse industrial applications. Traditional surfactant-based microemulsions (SBMEs) stabilize the interface between two typically immiscible liquids, forming various microstructures such as oil-in-water (O/W) droplets, water-in-oil (W/O) droplets, and bicontinuous phases. However, the use of surfactants poses environmental concerns, cost implications, and potential toxicity. Consequently, there is increasing interest in developing surfactant-free microemulsions (SFMEs) that offer similar benefits without the drawbacks associated with surfactants. In this study, we explore the formation and characteristics of a new surfactant-free microemulsion in a ternary system comprising water, ethanol, and heptanol. Advanced techniques are employed to characterize the microstructures and stability of surfactant-free microemulsions. These include electrical conductivity measurements, surface tension analysis, dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR). These methods have been extensively used in previous research on surfactant-free microemulsions (SFMEs) to reveal the properties and interactions within microemulsion systems. The area of interest is identified using these techniques, where silica nanoparticles are subsequently synthesized and then visualized using transmission electron microscopy (TEM).

Oil-in-water microemulsion of Arthrospira platensis carotenoid as antiphotooxidation in vitamin C beverages

Arthrospira platensis is a blue-green microalgae that has carotenoid as the main pigments, with the largest content being beta-carotene. Carotenoids are a type of pigment that is water insoluble, unstable, and has a limited bioavailability. One of the efforts to improve its solubility and stability, especially with regard to its anti-photooxidation capabilities, is to make it into a microemulsion. This study aimed to develop the most stable oil-in-water (O/W) microemulsion containing carotenoids from A. platensis for use as an antiphotooxidation agent in vitamin C beverages. Microemulsions consist of three distinct phases: oil, water and surfactant. The oil phase consisted of virgin coconut oil (VCO) or palm oil, with 7.5% and 15% and the aqueous phase was distilled water at a concentration of 65% or 80%. The surfactant used a combination of Tween 80, Tween 20, and Span 80 with a final hydrophilic-lipophilic balance or HLB value of 14.5. All microemulsion formulations were incubated for 24 hrs before being tested for stability by centrifugation at 3000 rpm for 30 mins, heating at 105oC for 5 hrs, and storage for 2 and 4 weeks. The resulting turbidity index was used to test the microemulsion's stability. The most stable microemulsion was chosen as a delivery system for carotenoid compounds. The carotenoid microemulsion was also tested by centrifugation, heating, and stability at different pH (6.5 and 4.2) and in varied ratios (1:1, 1:9 and 1:99). The results revealed that the concentration of oil and water phases in the microemulsion formulation influenced the microemulsion's stability. The best formulation obtained was a microemulsion with 7.5% of virgin coconut oil, 80% of water concentration, and surfactant with a ratio of 92:5.5:2.5 (Tween 80: Span 80:Tween 20). The most stable carotenoid microemulsion was a microemulsion with 100 ppm of carotenoid added. The carotenoid microemulsion was able to inhibit photooxidation at 4000 lux for 4 hrs. The vitamin C beverage model added with 6 ppm carotenoid microemulsion was able to inhibit photooxidation compared to the control and 12 ppm, for up to 6 hrs and there was a significant decrease in vitamin C and antioxidants after 24 hrs of photooxidation. A. platensis carotenoid microemulsion with a concentration of 6 ppm could inhibit photooxidation on vitamin C beverages for up to 6 hrs.

Design and Evaluation of Microemulsion-Based Drug Delivery Systems for Biofilm-Based Infection in Burns

Normal skin is the first line of defense in the human body. A burn injury makes the skin susceptible to bacterial infection, thereby delaying wound healing and ultimately leading to sepsis. The chances of biofilm formation are high in burn wounds due to the presence of avascular necrotic tissue. The most common pathogen to cause burn infection and biofilm is Pseudomonas aeruginosa. The purpose of this study was to create a microemulsion (ME) formulation for topical application to treat bacterial burn infection. In the present study, tea tree oil was used as the oil phase, Tween 80 and transcutol were used as surfactants, and water served as the aqueous phase. Pseudo ternary phase diagrams were used to determine the design space. The ranges of components as suggested by the design were chosen, optimization of the microemulsion was performed, and in vitro drug release was assessed. Based on the characterization studies performed, it was found that the microemulsion were formulated properly, and the particle size obtained was within the desired microemulsion range of 10 to 300 nm. The I release study showed that the microemulsion followed an immediate release profile. The formulation was further tested based on its ability to inhibit biofilm formation and bacterial growth. The prepared microemulsion was capable of inhibiting biofilm formation.Graphical

Studies on the Preparation of a Microemulsion Formulation of Matricaria Recutita Essential Oil and the Treatment of 2,4-Dinitro-Chlorobenzene- Induced Eczema in Mice by Inhibiting Inflammation.

Eczema, an inflammatory skin disease causing intense itching, is a function of a range of internal and external factors, impacting individuals of all ages and leading to economic loss. Inflammation is the most important manifestation of eczema, and Matricaria recutita essential oil (MREO) extracted from Matricaria recutita possesses excellent antibacterial and anti-inflammatory properties. In this study, Matricaria recutita microemulsions were prepared by the trans-phase emulsification method and their stability was determined by evaluating the relevant indexes. Establishment of 2,4-dinitro-chlorobenzene-induced AD model in mice. Detection of serum indexes of IL-6, IL-17, and TNF-α, and on pathological tissue sections, the HE staining, toluidine blue staining, immunohistochemistry, and observation were performed. The study obtained optimal conditions for the preparation of microemulsion formulations of Matricaria recutita. Through quality evaluation, it was found that the microemulsion increased stability, reduced irritation, and retained anti-inflammatory activity and therapeutic effects on eczema compared to Matricaria recutita essential oil (MREO). Studies have demonstrated that microemulsion formulations of Matricaria recutita and Matricaria recutita significantly down regulate the proinflammatory factors TNF-α, IL-17, and IL-6. It was shown by hematoxylin-eosin (HE) staining that both Matricaria recutita essential oil (MREO) and Matricaria recutita microemulsion (MRME) improved the inflammatory status of eczematous skin tissues in mice. The number of mast cells expressed in the tissues was decreased in the surface-treated group, as shown by toluidine blue staining. Additionally, the number of mast cells expressed in the tissues in the surface-treated group was reduced, as demonstrated by immunohistochemistry. Furthermore, immunohistochemistry revealed that MREO and MRME have immunomodulatory effects on the tissues. The study showed that microemulsion formulations of Matricaria recutita may serve as a novel remedy for eczema.

Formulation and Characterization of Emulgel Lornoxicam Containing Lemon Grass Oil as Penetration Enhancer.

Emulgel dosage form is an advanced form of transdermal drug de-livery. It is a combination of emulsion and gel in a definite ratio. Emulsions are incorporated into the gel with proper mixing. The emulsion present in emulgel can be either oil/water or water/oil, which is thickened by mixing it with a gelling agent. On the basis of the solubility of lornoxicam in various oils, a surfac-tant and a co-surfactant were selected for further research. For the preparation of emulgel, the emulsion was prepared with Smix (surfactant and co-surfactant) in a ratio of 1:2. The prepared emulsion was incorporated into different concentrations of carbapol 934 in a 1:1 ratio to make a homogenous emulgel. The emulgel was inspected visually to see if it had any phase behaviour, spreadabil-ity, or grittiness by applying it to a slide. All formulations were evaluated for pH, physical properties, drug content, spreadability, extrudability, swelling index, viscosity, and centrifu-gation. Franz diffusion cell was used to perform in-vitro release of formulation with the help of egg membrane. Among all formulations, F3 showed 83% release after 6 hours and showed acceptable physical properties like homogeneity, colour, consistency, pH value, spreadability, extrudability, and drug content. Thus, emulgel can be regarded as a more feasible drug delivery system for hy-drophobic drugs (lornoxicam) than the currently marketed formulation. Optimized emulgel formulation consists of a microemulsion of lornoxicam, 1 % of carbopol 934, propylene gly-col, sodium benzoate, lemon grass oil, glycerin, and distilled water. In the in-vitro release studies, pH 7.4 phosphate buffer emulgel formulation (F3) showed 83% after 6 hours. Emulgel was found to be stable under stable conditions. The emulgel of the poorly water-soluble drug (lornoxicam) was formulated. The components and their optimum ratio for the formulation of microemulsion were obtained by solubility studies and droplet size analysis. Thus, microemulsion can be regarded as a more feasible dose delivery system for lornoxicam than the currently marketed tablet, capsule, and injection formulations. Optimized microemulsion of lornoxicam was incorporated into the gel base. Therefore, it may be concluded that emulgel of lornoxicam can be used as a controlled-release dosage form of the drug for local application in rheumatoid arthritis.

Formulation of a stable diesel microemulsion using eco-friendly ionic liquids and investigation of particle size and fuel properties as an alternative fuel

Ecofriendly ionic liquids (ILs) were synthesized through amidation of ricinoleic acid, the main fatty acid in castor oil, followed by a quaternization reaction to solubilize ethanol in IL/diesel blends at different ratios. As a result, stable and highly renewable, low viscous microemulsion biofuels with high oxygen content were prepared. The prepared fuel samples combine the advantages of green ionic liquids and microemulsion properties. The chemical structures of ILs were confirmed with the aid of NMR and FTIR spectroscopy. DLS analysis revealed that the ethanol particles ranged in size from 8 to 18.1 nm in all samples. As ILs ratios decrease in microemulsion from 37 to 69%, the ethanol particle sizes increase from 10 to 25%. Ethanol shows good solubilization in diesel and IL-1 is more effective than IL-2 in ethanol solubilization at low percentages of ethanol due to more oxygen atoms besides three hydroxyl groups. The ternary phase diagram indicated that the microemulsion area in the case of using IL-1 is larger than that of IL-2. The fuel properties of the prepared microemulsions are nearly close to those of neat diesel and fall within the permitted range of ASTM D975. The viscosity and density values at low ratios of ILs are found to be very close to the values of the neat diesel at different temperatures. The prepared samples show a slight decrease in cetane number and heating value compared to diesel. However, they have improved flash points, cloud points, sulfur content, and acid value. The particle sizes were checked every week and the prepared samples showed high stability with the aid of the synthesized ILs. Moreover, the prepared microemulsions stayed in a transparent appearance for more than a year and no phase separation was observed.

Ex-vivo skin retention of crisaborole from microemulsion and micellar formulations

The aim of the present work was to optimize the delivery of crisaborole to the skin, incorporating the drug in topical formulations with a texture suitable also for application to the hairy skin. In particular we focused on microemulsions and micelles. As reference, the concentration of crisaborole in skin layers obtained with the commercial ointment Eucrisa®, was considered. Two microemulsions, one w/o and one o/w, were tested ex-vivo and both produced drug deposition into the skin comparable to the commercial formulation, but with higher delivery efficiency and with a non measurable permeation across the skin. Solutol®, TPGS and Soluplus® at different concentration were used for the preparation of crisaborole micellar solutions. Compared to the commercial formulation, all the micellar systems produced lower drug concentration in the skin layers, with the only exception of Soluplus® 6 %. However, due to differences in drug loading and thus in the applied dose, the delivery efficiency of all the formulation tested was higher compared to the commercial ointment. Moreover with Soluplus® 6 % formulation, a 5-fold increase in the retained/permeated ratio compared to the ointment was obtained. Two-photon microscopy studies showed that Soluplus® 6 % micelles do not permeate intact across the skin but disassemble in correspondence of the tissue surface.

Deep eutectic solvent microemulsions with abundant hydrogen ions in supercritical CO2 for decontamination of radioactive solid waste: Overcoming roadblocks to hydrogen ions deficiency

Deep eutectic solvents (DESs) dispersed in supercritical CO2 (SC-CO2) as microemulsions have shown promise for the removal of radioactive contaminants from solid surfaces. However, the current technology needs urgent improvement in terms of decontamination performance. This study reported a novel strategy to enhance the decontamination ability of DESs-in-CO2 systems by adding hydrogen ion (H+) supplemental reagents. The type and acidity of the added H+ reagents were found to be critical factors in dictating the decontamination performance. For instance, fluorinated carboxylic acids with higher acidity and higher CO2 affinity were more competitive for decontamination compared to other non-fluorinated carboxylic acids. Additionally, when nitric acid was used as the H+ supplemental reagent for microemulsions in SC-CO2, outstanding decontamination results were achieved. It could remove 99 % of UO3 contaminants on the specimen surfaces. The formation of microemulsions was demonstrated by molecular dynamics (MD) simulations. Meanwhile, low-cost nitric acid was more promising for scale-up applications. Remarkably, the versatility of the decontamination technology with the addition of nitric acid was demonstrated by its ability to completely decontaminate multiple radioactive wastes made of various materials, as well as different simulated radionuclides. Decontamination efficiency reached more than 99.0 %. More importantly, the DESs-in-CO2 systems with nitric acid also reduced the radioactivity of real radioactive metal waste to the clearance level with the decontamination efficiency reaching 99.0 %. Overall, this study provided valuable insights into the design of advanced decontamination technologies based on microemulsions of DESs in SC-CO2 and opened new avenues for the sustainable management of radioactive waste.

Molecular identification of rhamnolipids produced by Pseudomonas oryzihabitans during biodegradation of crude oil.

The ability to produce biosurfactants plays a meaningful role in the bioavailability of crude oil hydrocarbons and the bioremediation efficiency of crude oil-degrading bacteria. This study aimed to characterize the produced biosurfactants by Pseudomonas oryzihabitans during the biodegradation of crude oil hydrocarbons. The biosurfactants were isolated and then characterized by Fourier transform infrared (FTIR), liquid chromatography-mass-spectrometry (LC-MS), and nuclear magnetic resonance spectroscopy (NMR) analyses. The FTIR results revealed the existence of hydroxyl, carboxyl, and methoxyl groups in the isolated biosurfactants. Also, the LC-MS analysis demonstrated a main di-rhamnolipid (l-rhamnopyranosyll-rhamnopyranosyl-3-hydroxydecanoyl-3-hydroxydecanoate, Rha-Rha-C10-C10) along with a mono-rhamnolipid (l-rhamnopyranosyl-b-hydroxydecanoylb-hydroxydecanoate, Rha-C10-C10). In agreement with these findings, the NMR analysis confirmed the aromatic, carboxylic, methyl, sulfate moieties, and hexose sugar in the biosurfactants. The emulsion capacity of the biosurfactants decreased the surface tension of the aqueous system from 73.4 mN m-1 to around 33 mN m-1 at 200 mg L-1 as the critical micelle concentration. The emulsification capacity of the biosurfactants in the formation of a stable microemulsion for the diesel-water system at a wide range of pH (2-12), temperature (0-80°C), and salinity (2-20 g L-1 of NaCl) showed their potential use in oil recovery and bioremediation through the use of microbial enhancement. This work showed the ability of Pseudomonas oryzihabitans NC392 cells to produce rhamnolipid molecules during the biodegradation process of crude oil hydrocarbons. These biosurfactants have potential in bioremediation studies as eco-friendly and biodegradable products, and their stability makes them optimal for areas with extreme conditions.

Development and optimization of a methimazole microemulsion for topical application: Formulation characteristics and transdermal permeation.

Methimazole, an oral antithyroid drug, has recently gained attention for its skin-brightening effects when applied topically to treat melasma. This study aims to develop, optimize, and characterize a methimazole microemulsion as a novel, safe approach for local melasma treatment. We prepared microemulsion formulations containing 3% methimazole by combining appropriate amounts of surfactants (Tween 80 and Span 20), propylene glycol cosurfactant, and an oil phase (oleic acid-transcutol p at a 1:10 ratio). We then assessed droplet size, stability, viscosity, and skin permeation using rat skin models. The microemulsions' droplet sizes ranged from 7.06 to 28.13 nm, with viscosities between 120 and 254 centipoises. Our analysis identified droplet size, viscosity, and membrane release as significant independent variables. We determined the permeability parameters of the optimal formulation through rat skin, including steady-state permeability rate (Jss), permeability coefficient (p), lag time (Tlag), and apparent diffusion coefficient (Dapp). We found that the microemulsions' characteristics, physicochemical properties, and invitro release depended on the surfactant-to-cosurfactant ratio, water content, and oil content. We developed an optimal formulation with a high surfactant-to-cosurfactant ratio and low water and oil percentages. This formulation shows potential for commercialization and manufacturing of final products.

Facile in-situ fabrication of graphene oxide/poly(ionic liquid) composites and their adsorption performance for methyl orange

This work reveals a facile in-situ fabricating strategy for graphene oxide/poly(ionic liquid) composites toward the effective adsorption of methyl orange in aqueous solution. This synthetic route includes the formation of novel surfactant-free ionic liquid microemulsions and the stable solubilization of graphene oxide. To characterize the designed composites, FTIR, XRD, TGA, SEM, DSC, and XPS analyses were conducted, and the adsorption isotherms/kinetics of the designed composites toward methyl orange were further investigated. Results indicated that graphene oxide/poly(ionic liquid) composites can be in-situ synthesized facilely within the surfactant-free ionic liquid microemulsions, and the network structure of composites can be adjusted effectively by altering the dosage of co-solvent. In addition, the graphene oxide/poly(ionic liquid) composites prepared in situ exhibited a remarkable adsorption performance of methyl orange. These findings indicate the great application potential of graphene oxide/poly(ionic liquid) composites in the field of cationic dye adsorption.

Aggregation in Deep Eutectic Solvents (DESs): Formation of Polar DES-in-Nonpolar DES Microemulsions.

The versatility of environmentally benign and inexpensive deep eutectic solvents (DESs) lies in their widely varying physicochemical properties. Depending on its constituents, a DES may be highly polar or nonpolar in nature. This offers an enticing possibility of formation of novel nonaqueous microemulsions (MEs). Evidence of the presence of polar DES-in-nonpolar DES MEs is presented with reline (formed by mixing choline chloride and urea in 1 : 2 mol ratio) as the polar DES forming the ME pools, Thy : DA [formed by mixing thymol (Thy) and n-decanoic acid (DA) in 1 : 1 mol ratio] nonpolar DES as the bulk oil phase and nonionic surfactant Brij-35 as the emulsifying agent. While only sparingly miscible in Thy : DA, as high as 2.5 M reline can be solubilized in this DES in the presence of 100 mM Brij-35; reline loading (w Rel = [reline]/[Brij-35]) as high as 25 can be achieved. The ternary phase diagram of the Thy : DA/Brij-35/reline system reveals a clear and transparent single-phase region where MEs may be forming. Dynamic light scattering confirms the presence of MEs of 2-10 nm size. Even as up to 2.5 M (ca. 0.35 mole fraction) reline, whose dynamic viscosity (η) and electrical conductivity (κ) are very high, is added to 100 mM Brij-35 solution of Thy : DA, the η and κ values of the solution increase insignificantly, thus conforming to the formation of MEs in the solution. Fourier transform infrared (FTIR) absorbance spectra and fluorescence probe responses further indicate that reline is not dispersed in the medium but rather forms polar pools of the MEs. These novel nonaqueous polar DES-in-nonpolar DES MEs will not only expand the application potential of DESs but also offer a new class of organized media with widespread potential.

Formulation of double microemulsion based on pH-responsive PEG/PVA/zinc oxide as a potential nano-platform for drug delivery: Green synthesis, and physico-chemical characterization

The current workdeveloped a novel kind of pH-sensitive nanocarrier by combining a hydrogel nanocomposite composed of polyethylene glycol (PEG), polyvinyl alcohol (PVA), and zinc oxide nanoparticles (ZnO NPs) with an extensive surface area.To provide quality control, the nanocarriers were synthesizedusing the water/oil/water (W/O/W) emulsifying method to deliver quercetin (QC). Considering the compelling possibility of QCas a cancer treatment, it is imperative to overcome the challenges associated with its rapid release and poor solubility. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) were used to assess the nanocarrier’s crystalline structure and component interactions.The scanning electron microscopy (SEM) illustrationsconfirmed the surface uniformity of the nanocarrier and its spherical morphology. Dynamic light scattering (DLS) and zeta potential provide information on the nanocarrier’saveragesize, surface charge, and stability variations.High QC loading and encapsulationefficiencies were obtained, which were further improved uponaddition of ZnO NPs.The release kinetics of drug-loaded PEG/PVA/ZnO nanocomposites were investigated at pH=5.4 and pH=7.4, revealing an excellent controlledpH-sensitive release profile.The in vitro cytotoxicity of the nanocomposites was evaluated by MTT assay.As a result, a diminution in the total number of viableMCF-7 breast cancer cells when subjected to PEG/PVA/ZnO nanocomposites, compared with PEG/PVAsamples and the control groupsample, suggests that the addition of ZnO NPs has improved the cytotoxic activity of the nanocomposite.Hence, applyingPEG/PVA hydrogel encapsulated with ZnO NPs demonstrates significant promise inpH-sensitivecontrolled drug release.

A Comparative Study of Surfactant Solutions Used for Enhanced Oil Recovery in Shale and Tight Formations: Experimental Evaluation and Numerical Analysis.

Applying chemical enhanced oil recovery (EOR) to shale and tight formations is expected to accelerate China's Shale Revolution as it did in conventional reservoirs. However, its screening and modeling are more complex. EOR operations are faced with choices of chemicals including traditional surfactant solutions, surfactant solutions in the form of micro-emulsions (nano-emulsions), and nano-fluids, which have similar effects to surfactant solutions. This study presents a systematic comparative analysis composed of laboratory screening and numerical modeling. It was conducted on three scales: tests of chemical morphology and properties, analysis of micro-oil-displacing performance, and simulation of macro-oil-increasing effect. The results showed that although all surfactant solutions had the effects of reducing interfacial tension, altering wettability, and enhancing imbibition, the nano-emulsion with the lowest hydrodynamic radius is the optimal selection. This is attributed to the fact that the properties of the nano-emulsion match well with the characteristics of these shale and tight reservoirs. The nano-emulsion is capable of integrating into the tight matrix, interacting with the oil and rock, and supplying the energy for oil to flow out. This study provides a comprehensive understanding of the role that surfactant solutions could play in the EOR of unconventional reservoirs.

Peningkatan Aktivitas Afrodisiak Mikroemulsi Icariin, Ekstrak Purwaceng dan Ekstrak Pasak Bumi

Erectile dysfunction (ED) refers to medical issues concerning men's sexual health. Purwaceng, pasak bumi, and epimedium plants contain aphrodisiac compounds that can boost stamina, libido (sexual desire), and male fertility. The formula for microemulsions is 80: PEG 400: oil shavings in a ratio of 73.6711: 12.5705: 13.7584, with icariin, purwaceng, and pasak bumi added. The microemulsion system was created because it contained a large number of active ingredients. The stability of a microemulsion is further influenced by surfactants (tween 80) and cosurfactants (PEG 400) as emulsifiers, as well as the oil used as a solvent for the active component (bottled oil). The goal of this study was to create a microemulsion that would mix icariin, pasak bumi, and purwaceng substances to improve solubility and synergize pharmacological effects. The formulation is optimized using Simplex Lattice Design (SLD) to produce the optimal formula. The microemulsion formulations of icariin, pasak bumi extract, and purwaceng extract produce optimal microemulsions and enter into good microemulsion susceptibility. They can also increase the aphrodisiac effectiveness when compared to the administration of the single active substance icariin, pasak bumi extract, and purwaceng extract. As a result, this product exhibits microemulsion capabilities, allowing it to minimize dose while increasing effect.

Characterization and Animal Skin Irritations Investigation of Vemurafenib Microemulsion-Based Hydrogel Using Oily Ionic Liquid

Cutaneous melanoma accounts for a yearly mortality rate of 55,500 persons. The use of oral small-molecule kinase inhibitors, specifically targeting BRAFv600, has been licensed as the principal treatment strategy for managing both locally progressed and metastatic presentations of the condition. Approximately 30% of people on vemurafenib, a BRAFv600 inhibitor, have side effects when are taken orally. Objective: This research was attempted to develop a vemurafenib microemulsion by substituting conventional oil phases with ionic liquids (ILs). The microemulsions were created by dissolving vemurafenib in a combination of ionic liquid (1-Butyl-3-methylimidazolium hexafluorophosphate and 1-Octyl-3-methylimidazolium hexafluorophosphate) and surfactant (Triton x-100). Multiple tests were conducted to measure physical stability, pH determination, content homogeneity examination, and in vitro medicine release analysis. Four formulations of Vemurafenib microemulsions successfully met all criteria in the microemulsion characterisation and assessment tests. The droplet sizes in these microemulsions fell inside the range of microemulsions, which is less than 200 nm. They were then used to create microemulsion-based hydrogels, employing Carbamer 340 as a gelling agent by conducting a simple mixing method. Hydrogels formed from microemulsions containing 1-Octyl-3-methylimidazolium hexafluorophosphate demonstrated the ability to form clear hydrogels with desirable consistency. Regarding Ex-vivo permeability study and skin deposition the permeability profiles of GOT3 formula exhibits a permeability measurement of 33569± 344 mP.s at 6 rpm, whereas GOT4 demonstrates a permeability measurement of 54723± 380 mP.s at 6 rpm. During the skin irritation test, there was no apparent erythema and edema were observed when compared to the negative group. This may indicate that the designed microemulsion-based gel formulation demonstrates good biocompatibility with skin tissue. Topical delivery of vemurafenib is a promising route of drug administration to melanoma skin. Ionic liquids (ILs) have permeation-enhancing properties with either hydrophilic or lipophilic characteristics‎‎‎‎‎.

Interactive roles of co-solvents and lemon-oil composition in the fabrication of dilutable clear emulsions

Clear emulsions are used as flavor carriers by the beverage industry because of their favorable optical properties. A transparent microemulsion with small droplets requires a high concentration of surfactants, and is often non-dilutable, posing a significant challenge to their application in the food industry. The formation of dilutable microemulsions by modulating the compatibility of oil composition and co-solvents was studied. While single-fold lemon oil exhibited poor loading capacity overall, no precipitation occurred due to the stronger interaction between monoterpenes and sucrose monopalmitate (SMP). Conversely, emulsification of five-fold lemon oil with 20 % ethanol demonstrated a higher loading capacity and a stronger dilution stability than other lemon oils. This is likely due to the balanced composition of surface-active monoterpenes and other components in five-fold lemon oil which facilitated the effective use of micellar space and aided in the retention of both surfactants and co-solvents post-dilution. The emulsification of higher-folded lemon oil, however, was favored by the use of propylene glycol as a surfactant exhibiting stronger dilution stability than ethanol, though it required twice as much co-solvent. The high concentration of surface-active monoterpene in the lower-folded lemon oils competes with propylene glycol for interfacial incorporation. This study demonstrated that co-solvents and oil composition play interactive roles in producing dilutable optically clear emulsions, and it provides a blueprint for the food industry to design colloidal systems using a minimum of surfactants.