Mixture Of Tween Research Articles

Simvastatin-loaded solid lipid nanoparticles for enhanced anti-hyperlipidemic activity in hyperlipidemia animal model

The objective of current study was to develop solid lipid nanoparticles-loaded with simvastatin (SIM-SLNs) and investigate their in vivo anti-hyperlipidemic activity in poloxamer-induced hyperlipidemia model. Nano-template engineering technique was used to prepare SIM-SLNs with palmityl alcohol as lipid core and a mixture of Tween 40/Span 40/Myrj 52 to stabilize the core. The prepared SIM-SLNs were evaluated for physicochemical parameters including particle diameter, surface charge, morphology, incorporation efficiency, thermal behaviour and crystallinity. In vitro release profile of SIM-SLNs in simulated gastric and intestinal fluids was evaluated by using dialysis bag technique and anti-hyperlipidemic activity was assessed in hyperlipidemia rat model. SIM-SLNs revealed uniform particle size with spherical morphology, zeta potential of −24.9 mV and high incorporation efficiency (∼85%). Thermal behaviour and crystallinity studies demonstrated successful incorporation of SIM in the lipid core and its conversion to amorphous form. SIM-SLNs demonstrated a sustained SIM release from the lipid core of nanoparticles. SIM-SLNs significantly reduced the elevated serum lipids as indicated by ∼3.9 and ∼1.5-times decreased total cholesterol compared to those of untreated control and SIM dispersion treated hyperlipidemic rats. In conclusion, SIM-SLNs showed a great promise for improving the therapeutic outcomes of SIM via its effective oral delivery.

REDUCED ULCEROGENECITY FROM SELF-NANO EMULSIFYING DRUG DELIVERY SYSTEM OF PIROXICAM

Piroxicam is antiinflammatory non-steroidal (AINS) drug group that has anti-inflammatory, analgesic and antipyretic effects. Like most other AINS drugs, piroxicam has low solubility and has gastrointestinal (ulcerogenic) side effects on long-term use. The nano-emulsifying drug delivery system (SNEDDS) is one of the technologies that can be used to overcome it. This study aims to determine the effect of ulcerogenic SNEDDS piroxicam compared with piroxicam formulas instead of SNEDDS. This study uses white rats male strain SD age 2-3 months and weight 100-200 grams of 40 rats. Rats divided into 5 groups. Group I was a normal control group, the test animals were given only water. Group II was a suspending control group treated with a 1% polyvinylpyrrolidone (PVP) solution, group III is a carrier control group treated with SNEDDS carrier which is a mixture of tween 80, virgin coconut oil (VCO) and polyethylene glycol (PEG) 400, group IV was a group of piroxicam drugs suspended with piroxicam 1.08 mg/kg in 1% PVP, group V was treated with SNEDDS piroxicam.Treatment was done for 28 days. After treatment, the gastric of rats were taken to be observed for ulcerogenic effects. Observations were made macroscopically by looking at ulcer scores followed by histopathological observations of tissue. The ulcer score data from each group were analyzed using one-way ANOVAand LSD test. The results showed that the normal control group, 1% PVP suspension and carrier group had a ulcer index of 0.0, 0.0 and 0.0, while the piroxicam suspension group and the SNEDDS group had an ulcer index of 0.88 and 0.0. These results were confirmed by histopathologic results of SNEDDS piroxicam to decrease the effect of pyroxicam ulcerogenic with results in the piroxicam suspension group has ulcer with necrosis by neutrophil infiltration, lymphocytes and mast cells in the mucosal tunica to submucosa. In the SNEDDS piroxicam group there is erosion with necrosis of the mucosal tunica epithelium with infiltration of lymphocytes and mast cells in submucosal tunica. It can be concluded the SNEDDS piroxicam can decrease the ulcerogenic effect.

Folic acid receptor-targeted human serum albumin nanoparticle formulation of cabazitaxel for tumor therapy.

BackgroundWe previously developed cabazitaxel (CTX)-loaded human serum albumin nanoparticles (NPs-CTX) via a self-assembly method, and these NPs showed efficacy in prostate cancer therapy. Many studies have shown that the levels of folic acid (FA) receptor on the surface of various tumor cells are high. Therefore, FA-modified NPs-CTX may have enhanced antitumor effects compared with unmodified NPs-CTX.MethodsNPs-CTX were first prepared via self-assembly, and FA was conjugated on the surface of NPs-CTX through the -NH2 groups of the NPs to produce FA-NPs-CTX. The FA-NPs-CTX were evaluated in tumor cells with high FA receptor (FR) expression in vitro and in vivo.ResultsBoth NPs-CTX and FA-NPs-CTX exhibited good stability and morphology. Drug release from the NPs was not affected by FA conjugation. Compared with CTX dissolved in a mixture of Tween 80 and 13% ethanol (w/w) at a ratio of 1:4 (v/v) (Tween-CTX), the two nanoformulations had lower lytic activity against normal red blood cells. However, FA-NPs-CTX showed greater inhibition of tumor cells with overexpressed FR, compared with NPs-CTX, in the cytotoxicity experiments. Moreover, the cellular uptake of FA-NPs-CTX was enhanced through FR-mediated endocytosis in HeLa cells in vitro and HeLa xenograft tumors in vivo. Although Tween-CTX exhibited tumor growth inhibition similar to FA-NPs-CTX in vivo, this inhibition also caused adverse side effects; the median lethal dose (LD50) of Tween-CTX to mice was 5.68 mg/kg, while FA-NPs-CTX-treated mice survived at doses exceeding 400 mg/kg.ConclusionThe results showed that FA-NPs-CTX caused inhibition of tumor growth in a manner similar to that of Tween-CTX; however, the safety and tolerability of CTX were greatly improved by FA conjugation compared with those of Tween-CTX. In summary, FA-NPs-CTX have great potential in CTX delivery, and this formulation is a promising candidate for the treatment of cancers with high FR levels.

Characterization of Tween® Surfactants by MALDI TOF-MS and High Performance Liquid Chromatography in a Ternary Mobile Phase

AbstractDifferent hydrophobic and hydrophilic functionalities are produced in the reaction mixture of Tween® surfactants which affect the physiochemical properties of the final product. Only hydrophilic fractions and monoesters were separated in the binary mobile phase. MALDI TOF-MS of Tween® 40 revealed the identification of peaks separated in binary mobile phase (methanol-water). Liquid adsorption chromatography was performed on a gradient system on a SynergiTM fusion reverse phase column. Mobile phase composition used for this separation was a ternary phase gradient starting from 41 % methanol, 47 % acetone and going to 96 % acetone for the analysis time of 60 minutes. In the ternary mobile phase, gradient all the species such as polyethylene glycol, sorbitan and isosorbide ethoxylates, mono-, di- and triesters of sorbitan and isosorbide ethoxylates were well resolved in an of 60 minutes analysis time. The above separation mechanism can be employed for the analysis of polymeric multifunctional surfactant compositions.

Curcumin nanoemulsion as a novel chemical for the treatment of acute and chronic toxoplasmosis in mice.

BackgroundThe aim of this study was to prepare curcumin nanoemulsion (CR-NE) to solve the problems associated with poor water solubility and low bioavailability of CR and to test its efficiency in the treatment of acute and chronic toxoplasmosis in mouse models.Materials and methodsCR-NE 1% was prepared using spontaneous emulsification by soybean as oil phase; a mixture of Tween 80 and Tween 85 as surfactant; ethanol as cosurfactant and distilled water. Particle size and zeta potential of NE were assessed using Nano-ZS90 dynamic light scattering. Stability testing of NE was assessed after storage for 2 months at room temperature. In vivo experiments were carried out using 50 BALB/c mice inoculated with virulent RH strain (type I) and 50 BALB/c mice inoculated with avirulent Tehran strain (type II) of Toxoplasma gondii and treated with CR-NE (1% w/v), CR suspension (CR-S, 1% w/v), and NE without CR (NE-no CR).ResultsThe mean particle size and zeta potential of CR-NE included 215.66±16.8 nm and −29.46±2.65 mV, respectively, and were stable in particle size after a three freeze–thaw cycle. In acute phase experiment, the survival time of mice infected with RH strain of T. gondii and treated with CR-NE extended from 8 to 10 days postinoculation. The differences were statistically significant between the survival time of mice in CR-NE-treated group compared with negative control group (P<0.001). Furthermore, CR-NE significantly decreased the mean counts of peritoneum tachyzoites from 5,962.5±666 in negative control group to 627.5±73 in CR-NE-treated mice (P<0.001). Growth inhibition rates of tachyzoites in peritoneum of mice receiving CR-NE, CR-S, and NE-no CR included 90%, 21%, and 11%, respectively, compared with negative control group. In chronic phase experiment, the average number and size of tissue cysts significantly decreased to 17.2±15.6 and 31.5±6.26 µm, respectively, in mice inoculated with bradyzoites of T. gondii Tehran strain and treated with CR-NE compared with that in negative control group (P<0.001). Decrease of cyst numbers was verified by downregulation of BAG1 in treatment groups compared with negative control group with a minimum relative expression in CR-NE (1.12±0.28), CR-S (11.76±0.87), and NE-no CR (14.67±0.77), respectively, (P<0.001).ConclusionResults from the current study showed the potential of CR-S and CR-NE in treatment of acute and chronic toxoplasmosis in mouse models for the first time. However, CR-NE was more efficient than CR-S, and it seems that CR-NE has a potential formula for the treatment of acute and chronic toxoplasmosis, especially in those with latent bradyzoites in brain.

Optimizing the combination of conventional carbonaceous additives of culture media to produce lignocellulose-degrading enzymes by Trichoderma reesei in solid state fermentation of agricultural residues

Abstract Improving the production of lignocellulose-degrading enzyme such as cellulase and xylanase substantially increases the chance for cost-competitive production of cellulosic biofuel and other chemicals from such a biomass. In this study, the possible effects of carbonaceous additives including Tween 80, betaine, carboxymethyl cellulose (CMC) and lactose on cellulases and xylanase production were investigated individually or in combination. The enzymes were produced by Trichoderma reesei in solid state fermentation of wheat straw, wheat bran, rice straw and rice husk. The results proved that an individual additive could be an inducer or inhibitor based on the type of carbon source and targeted enzyme. For applying additives in combination, their roles depended on not only the type of carbon source and targeted enzyme but also their concentrations. Furthermore, a single additive with inhibitory role could be an inducer in combination with the other additives. For the best induction, the xylanase activity was about 469 U/gds with betaine as a single inducer. It increased to 218% with the mixture of Tween 80, betaine and CMC, supporting the combination of additives is more inducing. Applying the mixture of inducers can highly improve the process efficiency in lignocellulose-based biorefineries for both fuel and chemicals production.

The Effect of Essential Oil Formulas on Mortality and Oviposition Deterrent of Helopeltis antonii

&lt;p&gt;Citronella, clove and lemongrass oils are known to be toxic and repel certain pests. Mixing different essential oils (EOs) in the form of formula is expected to increase the insecticidal properties. The experiments aimed to examine the effect of EOs mixture formulas on mortality and oviposition deterrent of &lt;em&gt;Helopeltis antonii&lt;/em&gt;. The study was conducted at the green house of Indonesian Spices and Medicinal Crops Research Institute. A mixture of two EOs citronella + clove (1:1), lemongrass + clove (1:1), individual EO formulas, and their inert solution (mixture of tween 80, turpentine, and teepol) were tested on &lt;em&gt;H. antonii &lt;/em&gt;at 5 and 10 ml.l&lt;sup&gt;-1&lt;/sup&gt; concentrations. Parameters observed were the number of eggs laid, mortality of adults and nymphs of &lt;em&gt;H. antonii&lt;/em&gt;. The citronella + clove and lemongrass + clove formula at 10 ml.l&lt;sup&gt;-1 &lt;/sup&gt;deterred the oviposition of &lt;em&gt;H. antonii&lt;/em&gt; by 60.18 % and 46.56 % respectively. These formulas also caused adults mortality at 79.17 % and 62.50 %, as well as the nymphs mortality at 87.50 % and 82.50 % respectively. The citronella + clove and lemongrass + clove formulas tested had the same effectiveness compared to the commercial citronella oil formula. Therefore, these two formulas were potential to be tested in field to control &lt;em&gt;H. antonii&lt;/em&gt;.&lt;/p&gt;

Emulsification characteristics of nano-emulsions of solketal in diesel prepared using microwave irradiation

Glycerol acetonide, also termed solketal, which is chemically derived from bio-glycerol, was used as a combustion improver in the dispersed emulsion phase in this study. Nano-emulsions of ultra-low sulfur diesel (ULSD) containing nano-sized droplets of solketal were produced using microwave irradiation and compared with those produced by mechanical homogenizing. A non-ionic surfactant mixture of Tween 80 and Span 80, with a combined hydrophile-lipophile balance (HLB) adjusted to 10 by the weight proportion of the two surfactants was added to assist the emulsion formation. The characteristics of the emulsions produced using the two methods were analyzed and compared. The experimental results show that nano-emulsions can only form when up to 15 wt% of surfactant and no more than 5 wt% of solketal are added. The nano-emulsions from microwave irradiation had a larger mean droplet size, more concentrated one-peak distribution of droplet size, and lower kinematic viscosity and emulsification stability (ES) than those from the mechanical homogenizer. Higher solketal content in the emulsion increased the mean droplet size and kinematic viscosity of the nano-emulsions prepared using either method, and decreased the emulsification stability. The nano-emulsions with 3 wt% solketal in the dispersed phase also had superior characteristics including the lowest mean droplet size and highest ES. This is thus suggested to be the optimum composition.

Enhanced ocular bioavailability of fluconazole from niosomal gels and microemulsions: formulation, optimization, and in vitro–in vivo evaluation

Fungal keratitis may cause vision loss if it is not treated. Methods other than ocular delivery exhibited several limitations. No previous studies investigated and compared ocular bioavailability of fluconazole (FLZ) from niosomal gels and microemulsions. Niosomal gels of FLZ (0.3% w/w) based on Span® 60 and cholesterol (CH) using 1% w/w carbopol® 934 (CP) were evaluated. FLZ microemulsions (0.3% w/v) containing isopropyl myristate (IPM, as oil phase) and a 3:1 mixture of Tween® 80 (as surfactant) and polyethylene glycol 400 (PEG 400, as cosurfactant) were characterized. Optimized formulations were compared for their ocular bioavailability in rabbit’s. Nanoscopic niosomes (63.67–117.13 nm) and microemulsions (57.05–59.93 nm) showed respective negative zeta potential ranges of −45.37 to −61.40 and −20.50 to −31.90 mV and sustained release up to 12 h. Entrapment efficiency (EE%) of niosomes ranged from 56.48% to 70.67%. Niosomal gels were more sustainable than niosomes and microemulsions. The most stable niosomal gel based on Span® 60 and CH at a molar ratio of 5:5 and microemulsion containing 45% w/w IPM and 40% w/w of 3:1 Tween® 80-PEG 400 mixture significantly (p < 0.0001) enhanced FLZ ocular bioavailability compared with its solution. Niosomal gel showed higher bioavailability than microemulsion by ≈2-fold.

Preparation and characterization of citral-loaded solid lipid nanoparticles

Citral-loaded solid lipid nanoparticles (citral-SLNs) were prepared via a high-pressure homogenization method, using glyceryl monostearate (GMS) as the solid lipid and a mixture of Tween 80 (T-80) and Span 80 (S-80) at a weight ratio of 1:1 as the surfactant. The microstructure and properties of the citral-SLNs were characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). The chemical stability of citral in the citral-SLNs was analyzed by solid-phase microextraction gas chromatography (SPME-GC). The GC results showed that 67.0% of the citral remained in the citral-SLN suspensions after 12 days, while only 8.22% remained in the control. Therefore, the encapsulation of citral in the solid lipid can enhance its stability in acidic surroundings.

Rheological and mechanical characterization of curcumin-loaded emulsion-filled gels produced with whey protein isolate and xanthan gum

Reduction of the lipid content of food without textural loss can be carried out by producing emulsion-filled gels. This study aimed to produce and characterize heat-set mixed protein-polysaccharide (whey protein isolate-WPI and xanthan gum-XG) gels filled with curcumin-loaded solid lipid microparticles (SLM). Curcumin-loaded SLM were produced with babacu (Orbignyia speciosa) oil and triestearin using different surfactant (mixtures of tween 60 and span 80) concentrations. Gels produced with WPI, XG at pH 6.5 were characterized by rheology, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), water holding capacity (WHC) and instrumental colorimetry stability. SEM and CLSM analyses showed particulate gels and SLM homogeneously distributed in the biopolymer matrix. Filled gels showed higher values of WHC than non-filled gels. The type and concentration of SLM in filled gels affected their behavior when submitted to small or large deformations. The interactions among protein and surfactants chains, as well as the porosity of gels, influenced significantly in mechanical and rheological properties. Filled gels were more stable in terms of color than non-filled gel, indicating curcumin encapsulation in SLM was advantageous.

Size and Stability of Curcumin Niosomes from Combinations of Tween 80 and Span 80

The ratios of Tween 80 to Span 80 are important in controlling the physicochemical characteristics of curcumin niosomes. Thus, in this study the correlations of combination of Tween 80 and Span 80 at different ratios with the size and stability of curcumin niosomes were investigated. Initially curcumin was dissolved in chloroform and methanol (v/v= 3:1), followed by the preparation of niosomes by thin-film hydration method with the mole ratio of mixture of Tween 80 and Span 80 to cholesterol of 2:1. The ratios of Tween 80 to Span 80 in the mixture were set at 1:1, 1:9, 9:1, 2:3 and 3:2 with Hydrophilic-Lipophilic Balance (HLB) values of 9.65, 5.37, 13.93, 8.58 and 10.72, respectively. As expected, niosome barely formed at HLB value 13.93. This might be due to the molecule being hydrophilic and well hydrated which inhibits the formation of a stable bilayer in solution. It was found that the formulation which has higher Span 80 and lower HLB value leads to larger niosome before sonication. The largest niosome size achieved from Tween 80 to Span 80 ratio of 1:9 and 2:3 was 77.36 and 59.85 μm, respectively. On the other hand, for the ratio of 3:2, the largest niosome formed before sonication was less than 50.00 μm. After sonication, the niosome size reduced to less than 35.00 μm for all formulations. It was showed that formulation with Tween 80 to Span 80 ratio of 1:9 has superior curcumin entrapment efficiency and best stability during storage. The results demonstrated that appropriate ratio of Tween 80 to Span 80 was necessary for forming small and stable curcumin niosomes.

Thermodynamic investigation of binary surfactant mixtures of Tween 85/Triton X100 and 85/Triton X165 in water solution – Binary mixed micelles formation

Binary surfactant mixtures of Tween 85/Triton X100 and Tween 85/Triton X165 have been investigated in water solution over the temperature range from 273.15K to 323.15K. At the temperatures of 273.15K and 283.15K between different building units of binary mixed micelles, synergistic interactions exist whose size is not affected by difference in length of the polyoxyethylene chains.At higher temperatures, the longer polyoxyethylene chain of Triton X165 shows a more stabilizing effect in mixed micelle with Tween 85 than in mixed micelles of Tween 85/Triton X100. For the investigated binary mixed micelles, regular solution theory approximation about zero value of excess entropy of binary mixed micelle formation cannot be accepted.

Preparation and physicochemical characterization of ketoprofen-loaded emulsions

The objective of this study was to prepare ketoprofen-loaded emulsions. The emulsions were formulated by mixing soybean oil, surfactants (a mixture of Tween 20 and Tween 80), and distilled water. To determine the most suitable composition for the emulsions, a phase diagram was drawn, representing a mixture of soybean oil, surfactants, and distilled water. From the phase diagram, one-phase formulations were selected and the particle sizes of the formulations were compared. The stability of each formulation was confirmed over 4 weeks at 4 °C, by looking for any change in particle size. The effect of dilution on the pH of emulsion formulations was recorded. A soybean oil concentration of 5 % was sufficient to obtain emulsions. The surfactants used were a mixture of Tween 20 and Tween 80 in a 1:2 ratio, to ensure high ketoprofen solubility. Three formulations, termed E1, E2, and E3, produced emulsions with relatively small particles. The ketoprofen-loaded E1 formulation resulted in the smallest particles. The three formulations were physically stable for 4 weeks with no significant change in particle size. Dilution with distilled water did not alter the pH of the three emulsion formulations, but did change the conductivity. In conclusion, ketoprofen was solubilized by the emulsion formulation, and then remained stable when maintained at 4 °C; additionally, while the pH was unaltered, the conductivity of the formulation was changed by dilution with distilled water.

Preformulation and in vitro physicochemical characterization of fenofibrate-loaded emulsion

The objective of this study was to prepare a fenofibrate-loaded emulsion. The emulsion was formulated by mixing olive oil, surfactants (mixture of Tween 20 and Tween 80), and distilled water. To find the emulsion composition, the phase diagram was investigated based on the mixture of olive oil, surfactants, and distilled water. From the phase diagram, one-phase formulations were selected and particle sizes of those formulations were compared. Stability was confirmed for 4 weeks at 4 °C based on the change in particle size. The effect of dilution on the pH of the emulsion formulations was observed. The concentration of olive oil was 5 %, enough to obtain a small-sized emulsion. The surfactants were used as a mixture of Tween 20 and Tween 80 in a 1:2 ratio to show high solubility of fenofibrate. Three formulations, termed E1, E2, and E3, showed relatively small-sized emulsion. The fenofibrate-loaded E2 formulations showed smaller particle sizes than other formulations. The three formulations were physically stable for 4 weeks with no significant change in particle size. Dilution with distilled water did not alter the pH of the three emulsion formulations, but changed the conductivity. In conclusion, fenofibrate was solubilized by the emulsion formulation, the stability of the emulsion formulation was maintained at 4 °C, and the pH of formulation was not altered, but the conductivity of formulation was changed by dilution with distilled water.

Properties of nanocapsules obtained from oil-in-water nanoemulsions

Nanocapsules that are highly stable towards Ostwald ripening were obtained from oil-in-water nanoemulsions stabilized by the mixtures of Tween and Span surfactants. The structure adsorption layer in these nanoemulsions is discrete and, apparently, consists of domains with different surfactant ratios, and consequently, different melting points.

Influence of the additives of low-molecular alcohols on the adsorption of mixtures of tween and sodium dodecyl sulfate at the liquid–gas interface

The influence of nonelectrolyte additives (low-molecular alcohols) on the surface tension of individual and mixed solutions of nonionic and anionic surfactants at the air interface and on the patterns of their flotation extraction is investigated. The alcohol additives are found to reduce the surface tension of both individual and mixed surfactant solutions. Additive Fainerman–Miller model is shown to be used to predict the equilibrium surface tension of the surfactant solutions with alcohols.

Development and Characterization of Cinnamon Leaf Oil Nanocream for Topical Application.

Cinnamon leaf oil contains a high percentage of eugenol and has antimicrobial, antioxidant and antiinflammatory properties. However, the undiluted oil can cause irritation to the skin. Therefore, the aims of this study were to develop and evaluate cinnamon leaf oil nanocream using palm oil. Nanocream base was prepared using different ratios of oil, surfactants and water. The surfactant used were mixture of Tween 80:Carbitol or Tween 80:Span 65 at different hydrophile-lipophile balance values. The pseudoternary phase diagrams were constructed to identify the nanocream base areas and the results showed that the nanocream bases using Span 65 as co-surfactant produced bigger cream area. Fifteen formulations using mixtures of Tween 80:Span 65 were further evaluated for accelerated stability test, droplet size, zeta potential, rheological properties and apparent viscosity. The nanocream base which had an average droplet size of 219 nm and had plastic flow with thixotropic behavior was selected for incorporation of 2% cinnamon leaf oil. The nanocream containing cinnamon leaf oil had the average size of 286 nm and good rheological characteristics. The in vitro release study demonstrated that eugenol as the main constituent of cinnamon leaf oil was released for about 81% in 10 h. The short-term stability study conducted for 6 months showed that the cinnamon leaf oil nanocream was stable at a temperature of 25° and thus, cinnamon leaf oil nanocream is a promising natural based preparation to be used for topical application.

Optimal Development of a New Stable Nutraceutical Nanoemulsion Based on the Inclusion Complex of 2-Hydroxypropyl-β-cyclodextrin with Canthaxanthin Accumulated by Dietzia natronolimnaea HS-1 Using Ultrasound-Assisted Emulsification

Solubilizing the potent anticancer pigments in nanoemulsion (NE) systems containing 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) is a novel and promising strategy to incorporate them into water-based drug formulations. The concentration effects of sunflower oil (SO, 5.61–17.39% w/w), surfactant mixture of Tween 80 (T80) and Span 20 (S20) (1:1 weight ratio, 3.95–14.05% w/w), and the inclusion complex of HP-β-CD with canthaxanthin (CTX) synthesized by Dietzia natronolimnaea HS-1 (2.61–14.39% w/w) were evaluated to formulate a stable NE using ultrasound-assisted emulsification. The NEs were evaluated regarding droplet size and polydispersity index (span), physical stability, turbidity, and loss of antioxidant activity (LAA). Response surface modeling showed that the NEs containing 12% T80/S20, 8.30% SO, and 12% CTX/HP-β-CD had the lowest droplet size (105.5 nm), span (0.394), droplet growth ratio (0.112), turbidity (0.139), and LAA (9.36%). The predicted values obtained were close to the experimental values, indicating the suitability of the constructed models. Transmission electron microscopy and confocal laser-scanning microscopy also demonstrated that the formed droplets of the NEs produced at optimal formulation were spherical in the range of 20–100 nm. A significant correlation was found between droplet size with stability (r = −0.960, p < 0.01) and turbidity (r 2 = 0.876, p < 0.01) values.

Mixed micelles of binary surfactant mixtures Tween 40 – Na-3,12-dioxo-5β-cholanate and Tween 80 – Na-3,12-dioxo-5β-cholanate and their thermodynamic description and characterization

Regular solution theory (RST) was compared with model-independent thermodynamical methods (MIM) to analyze binary mixed micelles. It was found that if the molar fractions of the surfactants obtained using RST and MIM do not differ, the binary mixed micelles are symmetrical, according to the excess Gibbs energy. The algorithm used to analyze the binary surfactant mixtures, i.e., the method for determining whether the binary mixture of the surfactants is symmetrical and obeys RST, was developed.Binary mixtures of Tween 40 – Na-3,12-dioxo-5β-cholanate (T40-3,12-DOC) and Tween 80 – Na-3,12-dioxo-5β-cholanate (T80-3,12-DOC) were analyzed. Mixed micelles of T40-3,12-DOC were found to be more stable compared with the hypothetical ideal mixed micelles, i.e., they are primarily symmetrical, according to the excess Gibbs energy, but they do not obey RST. Mixed micelles of T80-3,12-DOC were non-symmetrical, according to the excess free energy, and were less stable then the ideal mixed micelles. With the increase in the molar fraction of T80 in the mixed micelle, the micelle became less stable and decomposed into micelles that comprised the building units.