Surfactant Ratio Research Articles

Preparation and Characterization of Oil Nanoemulsion Formulations of Beauveria bassiana (Bals.-Criv.)

This study aims to prepper stable thermodynamically dilutable nanoemulsion formulation of Beauveria bassiana with the lowest surfactant concentration that could improve its solubility stability. Formulations were prepared from oil in the water nanoemulsion region of phase diagrams subjected to thermodynamic stability tests. We found propanetriol was the highest germination rate at 5% and 10% concentration, 46.66 and 53.33%, respectively. Castor oil achieved a 43.00 germination rate at 1%. Tween 80 gave 54.33 % germination rate at 10%. While Tween 20 showed a 48 % germination rate at 5%. At the concentration, 1% Term 1284 gave 43.33% rate germination. Nanoemulsion composed of propanetriol and nonionic surfactants, with a mean particle size ranging from 25.08 to 75.35 nm, was formulated for various concentrations of the oils and surfactants. Water in oil emulsion was prepared using propanetriol oil, Tween 20, Tween 80, Term 1284, and water. Nanoemulsion of 25.08, 33.75, and 75.35 nm size was obtained at a 45: 15 % ratio of oil and surfactant, and it was found to be stable. The larger droplet size 75.35 nm of formulation Tween 20 and the smaller size was 25.08 nm in the formulation of Term 1284. The higher viscosity value was 16 mPas of formulation Tween 80, and the lowest value was 7.80 in the formulation of Term 1284. To demonstrate the possible employment of these systems, they were used to formulate a nanoformulation pesticide.

Impact of mixed surfactant composition on emulsion stability in saline environment: anionic and nonionic surfactants

The influence of anionic and nonionic surfactant ratios on emulsion stability in saline environments was investigated in the context of bilge water. Sodium laureth sulfate (SLES) and Triton X-100 were selected as surfactants likely present in bilge water emulsions. Interfacial tension results revealed that with 0.42 M NaCl, SLES is a more surface-active surfactant with a smaller head group area than Triton X-100. Increasing the proportion of SLES resulted in a higher surface charge, thus creating a greater repulsive interaction energy barrier between oil droplets, preventing flocculation. Size distribution results showed emulsions with 500 ppm surfactants at different surfactant ratios had long-term (more than 20 days) stability against coalescence. However, SLES-rich emulsions had smaller oil droplets (<8 μm) generated with the same energy input and were more stable against flocculation when compared to Triton X-100-rich emulsions. Visual observation showed more small oil droplets (<10 μm) with a slow creaming rate in SLES-rich emulsions than in Triton X-100-rich emulsions. Turbidity measurements showed that SLES-rich emulsions had higher remnant oil content in the subnatant than Triton X-100-rich emulsions, which is undesirable for phase separation and bilge water treatment. This work provides experimental results on how anionic and nonionic surfactant ratio influences emulsion properties in saltwater environments, which is valuable in developing strategies to minimize and remove remnant oil in bilge water.

Development of alendronate niosomal delivery system for gastrointestinal permeability improvement

In this study, the influences of surfactant types, the molar ratio of surfactant and cholesterol, and the molar ratio of drug load and total lipids on the size, zeta potential and drug entrapment efficiency of niosomes were statistically evaluated using a central composite design. Alendronic acid, a bisphosphonate compound was used to study. Stability, in vitro drug release and gastrointestinal permeability improvement of alendronate niosomal dispersion were also studied. The results showed that surfactant types, molar ratios of surfactant to cholesterol and molar ratios of drug load to total lipids had a significant effect on particle size, zeta potential and drug entrapment efficiency of niosomes (P < 0.05). The obtained niosomes were of a unilamellar spherical shape with negative zeta potential values. The niosomes prepared from Span 60 were larger and more entrapment efficient than those prepared from Span 20. In addition, the decrease of molar ratios of Spans and cholesterol resulted in the increase of zeta potential. The particle size and drug entrapment efficiency decrease when the molar ratio of Spans and cholesterol was decreased. Moreover, increase of drug load and total lipid molar ratio resulted in the decrease of zeta potential. However, particle size and drug entrapment efficiency could be increased with increasing molar ratio of drug loading and total lipid. Niosomes prepared from Span 60 showed a slower release rate than those prepared from Span 20. In the stability study, when stored at 4 °C for 90 days, only niosomes prepared from Span 20 have no significant change in particle size, zeta potential and the percentage of drug entrapment. The permeation of alendronate niosomes across Caco-2 cells monolayer showed that the average apparent permeability of alendronic acid from the niosomal dispersion prepared from Span 20 and Span 60 were significantly greater than that of the drug solution. This study revealed that niosomal dispersion can improve the oral bioavailability of alendronic acid.

Biodegradable Amphoteric Surfactants in Titration-Ultrasound Formulation of Oil-in-Water Nanoemulsions: Rational Design, Development, and Kinetic Stability.

Amphoteric amphiphilic compounds, due to their unique properties, may represent a group of safe and biocompatible surface-active agents for effective colloidal stabilization of nanoformulations. For this reason, the aim of this work was to develop and characterize the oil-in-water nanoemulsions based on two betaine-derived surfactants with high biodegradability, i.e., cocamidopropyl betaine and coco-betaine. In the first step, we investigated ternary phase diagrams of surfactant-oil-water systems containing different weight ratios of surfactant and oil, as the betaine-type surfactant entity (S), linoleic acid, or oleic acid as the oil phase (O), and the aqueous phase (W) using the titration-ultrasound approach. All the received nanoemulsion systems were then characterized upon droplets size (dynamic light scattering), surface charge (electrophoretic light scattering), and morphology (transmission electron as well as atomic force microscopy). Thermal and spinning tests revealed the most stable compositions, which were subjected to further kinetic stability analysis, including turbidimetric evaluation. Finally, the backscattering profiles revealed the most promising candidate with a size <200 nm for potential delivery of active agents in the future cosmetic, pharmaceutical, and biomedical applications.

Dual immobilization of Pd[sbnd]Cu nanoparticles on halloysite nanotubes by CTAB and PVP for automobile exhaust elimination

Low thermal stability and metal sintering are considered the reasons for the deactivation of three-way catalysts, especially on transition metals. Herein, using a versatile clay halloysite nanotubes (Hal) as a support and two surfactants, cetyltrimethylammonium bromide (CTAB) and polyvinylpyrrolidone (PVP), modified Hal with hydrophobic external surfaces and Pd-PVP colloids with various particle sizes were synthesized by adjusting the ratios of surfactants. As a result, modified Hal could make CuO nanoparticles coordinate with unsaturated Al in the internal lumen of Hal, which is favored to increase the CuO nanoparticle dispersion and inhibit their migration. In particular, Cu@HC-2 (Hal/CTAB weight ratio = 2) exhibited a higher n(Cu)/n(Al) ratio, surface active oxygen species and CuO species, which endowed better catalytic performance. The T50 of CO conversion decreased from 250 °C (unmodified Cu/Hal catalyst) to 180 °C. However, the NOx reduction is less effective due to the limited reducibility of transition metal. The reduced Pd-PVP nanoparticles with the molar ratio of PVP/Pd = 4 were immobilized on the Cu-based catalyst, which contributes to the smaller Pd0 nanoparticles and the maximum NOx conversion. Unexpectedly, excessive PVP-Pd may block the gas reaction with CuO species and weaken the CO and C3H8 oxidation.

Zwitterion-Driven Shape Program of Prodrug Nanoassemblies with High Stability, High Tumor Accumulation, and High Antitumor Activity.

Prodrug nanoassemblies have emerged as a promising platform for the delivery of anticancer drugs. PEGylation is a "gold standard" to improve colloidal stability and pharmacokinetics of nanomedicines. However, the clinical application of PEG materials is challenged by in vivo oxidative degradation and immunogenicity. Rational design of advanced biomaterials for the surface modification of nanomedicines is the hot spot of research. Here, a zwitterionic sulfobetaine surfactant is constructed as a novel surface modifier to coassemble with 10-hydroxycamptothecin-linoleic acid conjugate, with the classical PEGylated material as control. Interestingly, both the type and ratio of surfactants have profound impacts on the molecular mechanisms of the assembly of prodrugs, thereby affecting the pharmaceutical properties. Compared with PEGylated spherical prodrug nanoassemblies, zwitterion-modified prodrug nanoassemblies have distinct rod shape and superhydrophilic surface, and exhibit potent antitumor activity due to the combination of multiple advantages in terms of colloidal stability, cellular uptake, and pharmacokinetics. The findings illustrate the crucial role of zwitterionic surfactants as the surface modifier in the determination of in vivo fate of the prodrug nanoassemblies, and pave the way for the development of advanced nanomedicines.

Gellan Gum Hydrogels Filled Edible Oil Microemulsion for Biomedical Materials: Phase Diagram, Mechanical Behavior, and In Vivo Studies.

The demand for wound care products, especially advanced and active wound care products is huge. In this study, gellan gum (GG) and virgin coconut oil (VCO) were utilized to develop microemulsion-based hydrogel for wound dressing materials. A ternary phase diagram was constructed to obtain an optimized ratio of VCO, water, and surfactant to produce VCO microemulsion. The VCO microemulsion was incorporated into gellan gum (GG) hydrogel (GVCO) and their chemical interaction, mechanical performance, physical properties, and thermal behavior were examined. The stress-at-break (σ) and Young’s modulus (YM) of GVCO hydrogel films were increased along with thermal behavior with the inclusion of VCO microemulsion. The swelling degree of GVCO hydrogel decreased as the VCO microemulsion increased and the water vapor transmission rate of GVCO hydrogels was comparable to commercial dressing in the range of 332–391 g m−2 d−1. The qualitative antibacterial activities do not show any inhibition against Gram-negative (Escherichia coli and Klebsiella pneumoniae) and Gram-positive (Staphylococcus aureus and Bacillus subtilis) bacteria. In vivo studies on Sprague–Dawley rats show the wound contraction of GVCO hydrogel is best (95 ± 2%) after the 14th day compared to a commercial dressing of Smith and Nephew Opsite post-op waterproof dressing, and this result is supported by the ultrasound images of wound skin and histological evaluation of the wound. The findings suggest that GVCO hydrogel has the potential to be developed as a biomedical material.

Formation and characterization of microemulsion with novel anionic sodium N-lauroylsarcosinate for personal care

Microemulsions are unique clear systems comprising of oil, water, surfactant and cosurfactants that offered stimulating perspectives in various applications. The purpose of these study was to create a microemulsion using novel amino acid based anionic sodium N-lauroylsarcosinate (SNLS) surfactant for application in personal care formulations. Triglyceride oils such as caprylic acid, oleic acid and carboxylic acid ester isoamyl acetate were used as oil phase, while short chain alcohols like propanol and butanol were used as cosurfactants. The gradual variations happening in the microstructure of the microemulsions were explored via several complementary characterization techniques. Phase diagrams constructed with or without cosurfactants and using different ratio of surfactant/ cosurfactant (Smix) showed that largest microemulsion region was observed only in the presence of cosurfactant and from Smix of 1:1. Solubility of SNLS in pure water is around 30 wt%, which upsurges in presence of propanol or butanol up to around 85 wt%. This leads to increase in microemulsion region in phase diagram with increasing solubility of oils in the SNLS solution. Microemulsions were relatively stable at an ambient temperature of 27 °C. The optical microscopy, electrical conductivity and viscosity measurement were performed to examine the microstructural changes within the microemulsion region. Three different phases such as water in oil (w/o), bicontinuous, and oil in water (o/w) microemulsion were observed. Foaming behavior specifies increased foam stability of SNLS in the presence of certain amount of oils. Dynamic light scattering study supports the well-defined microemulsion stability even after the manifold dilution. The results obtained from this study may have implications for the developments of an appropriate tactic to prepare stable microemulsion from SNLS which could be exceedingly favorable for personal care formulations.

Tannin-Furanic Foams Formed by Mechanical Agitation: Influence of Surfactant and Ingredient Ratios.

With increasing demand of alternatives to oil-based lightweight materials, the development of tannin-based foams is getting more and more attention. In this paper, an alternative to traditionally used solvent-evaporation in the production of tannin-foams is presented. Mixing the tannin-furanic resin with different amounts of ionic and non-ionic surfactants at high agitational speed allows for the formation of highly porous, mechanically stable tannin-foams. Investigations on the influence of surfactant type and ingredient ratios on the foaming behavior and properties of the final foams were conducted. Materials obtained via this route do present extraordinary compression resistance (about 0.8 MPa), good thermal insulation (40 mW/m·K) and are suitable as a wastewater treatment agent at the end-of-life. It was shown that during mechanical blowing, homogeneous cross-sections and almost perfectly round pores form, leading to the high compression resistance. Investigations by means of Fourier transform infrared and 13C nuclear magnetic resonance spectroscopy show that the milder reaction environment leads to more linear poly(furfuryl alcohol)-tannin chains. This new type of tannin foam allows for use in various different fields of application ranging from durable building insulation to wastewater treatment.

Folate Conjugated Solid Lipid Nanoparticle: Formulation Development, Optimization, and Characterization

Objective: The current paper represents the development, optimization, and characterization of paclitaxel-loaded folate conjugated solid lipid nanoparticles (FA-SLNs). Methods: The ligand (FA-SLNs) conjugated and non-conjugated SLNs (PTX-SLNs) were prepared by hot homogenization method. Both of the formulations (FA-SLNs and PTX-SLNs) were optimized with various parameters i.e. drug loading, stirring time, stirring speed, particle size, and polydispersity index, and characterized. The in-vitro drug release study was performed in different pH environments by using the dialysis bag method. The surface morphology and particle size were determined through scanning electron micorscopy and Transmission Electron Microscopy respectively, The SLNs formulations were also evaluated for the stability study. Result: The particle size of PTX-SLNs and FA-SLNs was determined and found to be 190.1±1.9 and 231.3±2.3 nm respectively. The surface morphology of the SLNs indicates that the prepared formulations are round-shaped and show smooth surfaces. The TEM study indicated that particles were in the range of 100-300 nm. The entrapment efficiency and drug loading capacity of FA-SLNs were found to be 79.42±1.6% and 17.3±1.9%, respectively. In-vitro drug release study data, stated that the optimum drug release was found in an acidic environment at pH 4.0, that showed 94.21% drug release after 16 hours and it proves that optimized formulation FA-SLNs will gave the sustained and better release in tumor tissue that owing acidic environment because of the angiogenesis process. Conclusion: In this research paper, different formulation parameters, found to influence fabrication of drug into Solid lipid nanoparticles, were optimized for high entrapment efficiency and drug loading. The most important parameters were drug:lipid ratio, drug:polymer ratio and lipid: surfactant ratio. Higher in-vitro drug release was observed in pH 4 as compared to the pH 7.4. These result data concludes that FA-SLNs formulation was successfully prepared, optimized and characterized.

Strength optimization of cementitious composites reinforced by carbon nanotubes and Titania nanoparticles

Carbon nanotubes (CNTs) and titanium dioxide (Titania) nanoparticles are simultaneously incorporated in a cement slurry, and their influence on the mechanical characteristics is investigated. Response surface methodology (RSM) is employed to maximize the strength properties at various incorporation ratios of CNT-COOHs, Titania nanoparticles, and surfactant following the Box-Behnken Design. The morphology and microstructure of the specimens are characterized by XRD, FTIR, and FESEM. According to the experimental results and the ANOVA analysis, it can be concluded that the simultaneous use of Titania nanoparticles and CNT-COOHs significantly enhanced the flexural and compressive strength of cement. The incorporation of Titania nanoparticles displays the most significant effect on compressive strength, mostly due to their nano-filling effect and the preparation of hydration products as nucleation sites. This study also proposes a new, faster and easier, method for the prediction of optimum weight percentages of nanomaterials and surfactants for experimental work.

Lipid-based formulations of microemulsion-loaded oleogels for the oral delivery of carvedilol

This work aimed to develop controlled-release lipid-based formulations of microemulsion-loaded oleogels for the oral delivery of the poorly soluble drug carvedilol (CARV). The microemulsion-loaded oleogels were prepared by the oleogelator Compritol® 888 (CP888). CARV was loaded into submicron-sized emulsions (CARV-MEs) of various ratios of surfactant and cosurfactant. The CARV-MEs were entrapped into CP888-based oleogels, forming CARV-ME oleogels. The rheological properties and dissolution studies of the CARV-ME oleogels were determined. MTT assay test was performed to ensure the safety of oleogel formulations. The optimized formulation of CARV-ME oleogel was subjected to stability studies. The results revealed that CARV-MEs were thermodynamically stable of spherical globules of average size 13.3–57.4 nm, polydispersity index (PDI) range of 0.24–0.52, and interfacial tension of 29.9 ± 0.2 mN/m. Oleogels exhibited viscoelastic properties with more elastic behavior. The drug release rate was found to be dependent on the surfactant/cosurfactant ratio. A negative correlation was found between surfactant concentration and IC50. The optimized CARV-MEs oleogel was stable for 3 months at various storage conditions. In conclusion, the entrapment of the CARV-MEs, with various surfactant to cosurfactant ratios, into oleogels influences the dissolution rate and mechanism of drug release and the safety of CARV-MEs oleogels.

Lipid-Based Ionic-Liquid-Mediated Nanodispersions as Biocompatible Carriers for the Enhanced Transdermal Delivery of a Peptide Drug.

Lipid-based biocompatible ionic liquids (LBILs) have attracted attention as carriers in transdermal drug delivery systems (TDDSs) because of their lipophilic character. In this study, we report the formulation of a peptide-LBIL complex microencapsulated in an oil phase as a potential carrier for the transdermal delivery of leuprolide acetate as a model hydrophilic peptide. The peptide-LBIL complexes were prepared via a water-in-oil emulsion composed of 1,2-dimyristoyl-sn-glycerol-3-ethyl-phosphatidylcholine (EDMPC), a fatty acid (stearic, oleic, and linoleic acid)-based LBIL, and cyclohexane followed by freeze-drying to remove the water and cyclohexane. Then, the peptide-LBIL complexes were nanodispersed and stabilized in isopropyl myristate (IPM) using sorbitol laurate (Span-20). Ionic-liquid-in-oil nanodispersions (IL/O-NDs) were prepared with varying weight ratios of LBILs and Span-20 as the surfactant and the cosurfactant, respectively. Keeping the overall surfactant constant at 10 wt % in IPM, a 5:5 wt % ratio of surfactant (IL) and cosurfactant (Span-20) in the IL/O-NDs significantly (p < 0.0001) increased the physiochemical stability, drug-loading capacity, and drug encapsulation efficiency. The in vitro and in vivo peptide delivery across the skin was increased significantly (p < 0.0001) using IL/O-NDs, compared with non-IL-treated groups. Of all of the LBIL-based formulations, [EDMPC][Linoleate]/O-ND was considered the most preferable for a TDDS based on the pharmacokinetic parameters. The transdermal delivery flux with [EDMPC][Linoleate]/O-ND was increased 65-fold compared with the aqueous delivery vehicle. The IL/O-NDs were able to deform the lipid and protein arrangements of the skin layers to enhance the transdermal permeation of the peptide. In vitro and in vivo cytotoxicity studies of the IL/O-NDs revealed the biocompatibility of the LBIL-based formulations. These results indicated that IL/O-NDs are promising biocompatible carriers for lipid-peptide TDDSs.

Study on foam extinguishing agent based on mixed system of branched short-chain fluorocarbon anionic and hydrocarbon cationic surfactants

The traditional aqueous film-forming foam extinguishing agent (AFFF) plays an important role in fighting liquid fires, but its environmental hazard are also increasingly prominent. The key component of conventional AFFF is fluorocarbon surfactant containing perfluorinated C8 segment, which is one of the most refractory organic pollutants in the world. In this paper, a perfluorinated branched short-chain alkyl side chain fluorocarbon anionic surfactant with high surface activity and simple synthesis route was prepared. The surface activity and aggregation behavior of the mixed solution of fluorocarbon and hydrocarbon surfactants were studied by surface tension meter and transmission electron microscope (TEM). When the mixture ratio of fluorocarbon and hydrocarbon surfactant reached 1:10, the addition of cetyltrimethylammonium bromide (CTAB) had little effect on the interfacial adsorption, but could significantly reduce the critical micelle concentration (CMC) of fluorocarbon surfactant. Meanwhile, three kinds of environment-friendly AFFF formulations (F-1, F-2, F-3) were designed with the mixed system of different hydrocarbon surfactants and this fluorocarbon anionic surfactant as foaming agents. The foam properties revealed the F-2 possessed excellent foam performance, the initial foam height h0 was 120 mm, and the 25% drainage time was 240 s, extinguishing time was 30 s, burn-back time was 760 s.

Image quality radiographic testing on the making of trabeculae genu phantom by using ingredients surfactant

Exposure to radiation can be dangerous for the body. Hence why we need an effort to minimalize the effects of radiation received, especially for students and lectures during practicum that uses source of radiation. One of the efforts that can be done is to use phantom radiology so that there is no need to expose living things. Previous research has done to make phantom radiology by using gypsum instead of human bones and acrylic as a substitute for soft tissue (human flesh). However, this research still has a shortage which is trabeculae cannot be formed in the phantom produced. The purpose of this study was to determine whether the surfactant solution could be used to form trabeculae in phantom genu by using in the concentration of surfactants with a ratio of 2: 1. The research was conducted in three stages, namely designing the genu phantom and trabecular phantom, printing genu phantoms and trabeculae, and conducting radiographic quality tests of genu phantom. Trabeculae in phantom genu have been successfully made with a water and surfactant ratio of 2:1. Radiographic quality tests showed good detail, sharpness and contrast. The presence of trabeculae and soft tissue is apparent. Surfactants with a ratio of 2:1 can be used to form trabeculae on phantom genu with good quality in radiographic test results.

Formulation and characterization of Eleutherine palmifolia extract-loaded self-nanoemulsifying drug delivery system (SNEDDS).

This study aimed to determine the effect of different components and ratios of oil, surfactant, and cosurfactant on E. palmifolia extract-loaded SNEDDS. E. palmifolia extract loaded SNEDDS was formulated from virgin coconut oil, Miglyol 812 as oil, using Tween 80 and Transcutol as surfactants, as well as propylene glycol and PEG 400 as cosurfactants. The optimization design formula consisted of eight design formulas in five ratio formulas, thus a total of 40 formulas were optimized using different components and ratios of oil, surfactant, and cosurfactant. These ratios used were 1:1:1, 1:2:1, 1:3:1, 1:4:1, as well as 1:5:1, and the formula's components were determined based on the optimization results. The optimal formula of E. palmifolia extract loaded SNEDDS had the ratio 1:1:1 (formula A) of Miglyol 812:Tween 80:PEG 400 and 1:3:1 (formula E) of Miglyol 812:Tween 80:propylene glycol. Meanwhile, the optimal formulation characteristics showed a transmittance value above 90%, pH range of 5.10-5.20, 2.21-14.51cP viscosity, emulsification time below 120s, and particle size of 24.71-136.77nm. The optimal formula of E. palmifolia extract-loaded SNEDDS, were obtained using different components and ratios. These are Miglyol:Tween 80:PEG 400 at a component ratio of 1:1:1 (formula A) and Miglyol 812:Tween 80:propylene glycol at a component ratio of 1:3:1 (formula E).

Anionic and Cationic Surfactant Synergism: Minimizing Precipitation, Microemulsion Formation, and Enhanced Solubilization and Surface Modification

AbstractAnionic–cationic surfactant mixtures are known to exhibit synergistic effects (e.g., low critical micelle concentration, ultralow interfacial tension, middle phase microemulsion formulation, and increased solubilization and adsolubilization). However, the anionic–cationic surfactant mixtures are also prone to form other unique phases such as precipitates, gels, and coacervates in place of middle‐phase microemulsions. Research summarized in this article demonstrates that asymmetric anionic–cationic surfactant mixtures have been shown to promote middle‐phase microemulsions instead of these other phases, albeit with a slight decrease in synergism when using these asymmetric mixtures. The use of anionic–cationic surfactant mixtures also is shown to enhance or decrease surfactant adsorption depending on anionic–cationic surfactant ratios. Middle‐phase microemulsion formation is demonstrated using anionic‐rich or cationic‐rich alcohol‐free microemulsions by anionic–cationic ratio scans while also reducing or eliminating electrolyte requirement. Solubilization and adsolubilization are shown to increase for mixed anionic–cationic surfactant systems, especially for hydrophobic solutes. Thus, by exploiting these synergisms while avoiding phase separation, properly designed anionic–cationic surfactant mixtures can be advantageous for a wide range of applications.

Efficient treatment of crude oil-contaminated hydrodesulphurization catalyst by using surfactant/solvent mixture

The purpose of this work is to investigate desorption efficiency for regenerating a crude oil-contaminated catalyst by using an ex-situ surfactant/solvent washing technique. We employed six types of surfactants and solvents for optimization, and established an optimal mixture of surfactant and solvent for the removal of crude oil from the contaminated catalyst. The efficiency of the surfactant/solvent mixture for the removal of crude oil from the contaminated catalyst was determined based on the mass ratio of surfactant to solvent, contact time, pH, and temperature. The raw catalyst, crude oil-contaminated catalyst, and after washing catalyst were characterized by interracial rheometer, zeta-potential analyzer, and scanning electron microscope. We found that the Brij-58/1,2-dimethylbenzene mixture could provide superior crude oil removal efficiency. At a higher mass ratio of 1,2-dimethylbenzene, the crude oil removal rate of the contaminated catalyst exceeds 95%. This result is attributed to the addition of the solvent to the surfactant solution. The solvent can significantly decrease the surfactant’s CMC and increase the micelle’s number, thereby enhancing the mixture’s washing efficiency. Since aromatic solvents and crude oil components have similar structures in terms of polarity and aromaticity, the Brij-58/1,2-dimethylbenzene mixed system has a strong affinity for crude oil components.

Nanoemulsion Formulation of Ocimum gratissimum Essential Oil and Its Antifungal Activity Against Penicillium digitatum.

Plant-derived essential oils and extracts are known to be effective against many microorganisms. The essential oil obtained from fresh leaves of Ocimum gratissimum possessed promising antifungal activity against Penicillium digitatum. The antifungal potential of O. gratissimum essential oil can be markedly improved with the use of nanotechnology. O. gratissimum essential oil based nanoformulations were prepared using non-ionic surfactant and water by ultrasonication. The process was optimized for parameters such as surfactant concentration and sonication time to achieve minimum droplet diameter with high physical stability. Stable O. gratissimum essential oil nanoemulsions were obtained for 1:1 ratio (v/v) of essential oil and surfactant with mean droplet diameter of 259.4 nm for 10 min sonication time. Essential oil and all nanoemulsions were evaluated for their antifungal activity against P. digitatum of kinnow fruit by poisoned food technique. The nanoemulsion (1:1, 10 min) showed the highest growth inhibition (1 × 10⁴ CFU ml-1, 96%) against P. digitatum followed by pure oil (13 × 10⁴ CFU ml-1, 85%) on 15th day of incubation. Scanning electron and optical microscopy results further revealed stronger suppressive activity of O. gratissimum essential oil nanoemulsions for spore germination and hyphal elongation of P. digitatum than pure oil.

Development of ketorolac tromethamine loaded microemulsion for topical delivery using D-optimal experimental approach: Characterization and evaluation of analgesic and anti-inflammatory efficacy

Aim of the present study was to evaluate the potential of microemulsions for the transdermal delivery of ketorolac tromethamine. The pseudo ternary phase diagram, 3 D Optimal mixture design was used to develop the microemulsion of desired properties. Seventeen trial runs were executed by using three different variables, percent content of oil, water and the optimized ratio of surfactant and co-surfactant whereas the responses investigated were percentage transmittance and Globule size. This microemulsion system was composed of, eucalyptus oil, Methyl Salicylate, tween 80, labrafil 1944 M, and butanol. The optimized microemulsion was characterized by pH, Zeta Potential, Globule size, Polydispersity Index, and Viscosity. The surface morphology of microemulsion globules was performed by Transmission Electron Microscopy (TEM). Ex-vivo permeation study and in-vitro drug release study (flux, Permeability coefficient, and Enhancement ratio (Er)) was also performed by using excised goat skin in a modified Franz diffusion cell. The stability study of the formulations was performed at three different temperature conditions for 90 days to prove the stability of the formulation. Optimized MEK-1 formulation was assessed for its anti-inflammatory activity by Croton oil-induced ear edema test and Croton oil-induced capillary permeability. Additionally, analgesic activity was also performed by Formalin Test and Heffner's tail clip method. The study concluded that optimized microemulsion has potential and can be used as an alternative tool for the delivery of ketorolac tromethamine via the transdermal route.