Spontaneous Emulsification Research Articles

Precise Tailoring of Polyester Bottlebrush Amphiphiles toward Eco‐Friendly Photonic Pigments via Interfacial Self‐Assembly

AbstractBiodegradable photonic microspheres with structural colors are promising substitutes to polluting microbeads and toxic dyes. Here, amphiphilic polyester‐block‐poly(ethylene glycol) bottlebrush block copolymers (BBCPs) with polylactic acid or poly(ϵ‐caprolactone) as the hydrophobic block are synthesized and used to fabricate eco‐friendly photonic pigments. Molecular parameters of BBCPs, including rigidity and symmetry, are precisely tailored by variation of side chain lengths, which enables effective manipulation of interfacial tension (γ). Organized spontaneous emulsion mechanism is enabled only whenγfalls in a suitable range (10.6–14.3 mN m−1), producing ordered water‐in‐oil‐in‐water multiple emulsions and ordered porous structures. Consequently, highly saturated and tunable structural colors are observed due to coherent light scattering from the porous structures. Such photonic materials are nontoxic as confirmed by careful safety tests using aquatic model organisms.

Precise Tailoring of Polyester Bottlebrush Amphiphiles toward Eco-Friendly Photonic Pigments via Interfacial Self-Assembly.

Biodegradable photonic microspheres with structural colors are promising substitutes to polluting microbeads and toxic dyes. Here, amphiphilic polyester-block-poly(ethylene glycol) bottlebrush block copolymers (BBCPs) with polylactic acid or poly(ϵ-caprolactone) as the hydrophobic block are synthesized and used to fabricate eco-friendly photonic pigments. Molecular parameters of BBCPs, including rigidity and symmetry, are precisely tailored by variation of side chain lengths, which enables effective manipulation of interfacial tension (γ). Organized spontaneous emulsion mechanism is enabled only when γ falls in a suitable range (10.6-14.3 mN m-1 ), producing ordered water-in-oil-in-water multiple emulsions and ordered porous structures. Consequently, highly saturated and tunable structural colors are observed due to coherent light scattering from the porous structures. Such photonic materials are nontoxic as confirmed by careful safety tests using aquatic model organisms.

A low energy approach to develop nanoemulsion by combining pea protein and Tween 80 and its application for vitamin D delivery

Protein stabilized nanoemulsions have attracted interest as delivery systems of bioactive molecules for improved absorption. However, such nanoemulsion systems are usually prepared by high energy approaches, which are less sustainable, and the heat generated during the processes may degrade sensitive bioactive molecules. Hence, this study focused on developing a cost effective and environmentally sustainable way of nanoemulsion preparation for delivery of vitamin D. This research presents a low-energy approach to prepare a complex nanoemulsion by combining pea protein and Tween 80 together, and prepared by spontaneous emulsification method as delivery systems of vitamin D. A “clusters on string” structure was proposed for the obtained nanoemulsions with average size of around 200 nm, featuring Tween 80 stabilized micelles clustered together on pea protein polymeric chains. The in vitro assays using Caco-2 cells indicated that both nanoemulsions stabilized by Tween 80 alone and the complex nanoemulsion could efficiently improve vitamin D uptake by ≥ 2.5 folds as compared to free vitamin D suspension. The transport efficiency of vitamin D across Caco-2 cells for the complex nanoemulsion was 5.6 folds higher than free vitamin D suspension and 2.3 folds higher than nanoemulsions stabilized by Tween alone. Therefore, this study has provided a new method to prepare and stabilize complex nanoemulsions by a combination of Tween 80 and pea protein as emulsifiers for efficient delivery of bioactive molecules.

Preparation, Process Optimization and Cytotoxicity Evaluation of Lyophilized Etoposide Loaded Nanoparticles

The purpose of this study was to develop freeze dried Polylactide-co-glycolide (PLGA) nanoparticles loaded with etoposide intended to be administered intravenously with improved therapeutic efficacy of the drug and thereby reduced dose related toxicity associated with it. The etoposide loaded nanoparticles were prepared using modified spontaneous emulsification solvent diffusion method (SESD).The in Vitro release study of etoposide loaded Polylactide-co-glycolide (PLGA)–Nanoparticles NP was carried by dialysis bag diffusion technique.The incorporation efficiency was found to be higher in modified SESD technique than emulsification solvent evaporation method. The release behavior of etoposide exhibited a biphasic pattern characterized by an initial burst release followed by a slow and continuous release. The nanoparticles were characterized by particle size, zeta potential, polydispersity index, DSC and FTIR. The long term stability was achieved by lyophilisation technique. The cell line study using XTT assay on LNCaP prostate tumor cell lines revealed that etoposide loaded nanoparticles showed greater cancer cell inhibition compared to plain nanoparticles and marketed conventional formulations.

A Novel Approach of Leflunomide Nanoemulgel for Topical Drug Delivery System

Objectives: This research’s primary goals are Leflunomide (LFD) nanoemulgel formulation and characterization for topical administration. Materials and Methods: A pseudo ternary phase diagram was created utilizing castor oil, Tween 20 as the surfactant, PEG 300 as a co-surfactant, and ethanol as the cosolvent. Spontaneous emulsification was used to create LFD-nanoemulgel, which is now commercially available. Gel matrix Carbopol 934 was employed to generate nanoemulgel in the prepared nanoemulsion. Studies on the LFD-globule nanoemulgel’s size, physical appearance, viscosity, spreadability, TEM, FTIR drug content, release kinetics, and stability contributed to its characterization and assessment. Optimum nanoemulgel formulation contained 6% castor oil, 36% Tween 80 and PEG 300 as Smix (surfactant and co-surfactant mixture), 46% water, and 12% w/w carbopol 934. Results: The produced nanoemulgel was translucent and had a zeta potential of 26.12 mV and a particle size of 113.55 ± 1.73 nm. The improved formulation has a drug release rate of 98.13% ± 1.20%. They were determined to be ideal for pH, viscosity, and spreadability. According to the stability analysis, the generated nanoemulgel was shown to be stable at temperatures ranging from 25 ± 45°C, according to the stability analysis results. Conclusion: An effective formulation for topical medication delivery using LFD-loaded nanoemulgel has been developed. It may be an alternative drug therapy to the topical application of drugs to treat arthritis.

Black seed and rosemary nanoformulations as green insecticides for the granary weevil, Sitophilus granarius (L.) (Coleoptera: Curculionidae).

The development of nano-insecticides has attracted much interest in the last decade because it has the potential to result in an alternative pest-management strategy and also reduce the risk of chemically based insecticides. Herein, native rosemary (Rosmarinus officinalis) and black seed (Nigella sativa) oils were utilized for preparing their nanoemulsions by spontaneous emulsification method in the presence of tween 80 as a structure-directing agent. The prepared nanoemulsions were explored for granary weevil, Sitophilus granarius (L.), adults control and compared with their oils. Within the typical droplet sizes of 100 and 224nm, both rosemary and black seed nanoemulsions were found to be physically and thermodynamically stable. The insecticidal activity of the nanoemulsions was higher than that of the crude oils. After 24h of exposure, the LD50 values of rosemary and black seed nanoemulsions were estimated to be 102.56 and 35.08µg/g, respectively, compared to 188.95 and 210.09µg/g of their oils. These results revealed that the droplet size and chemical composition of the nanoemulsion are the significant factors that affect their toxicity. Surprisingly, the nanoemulsions had no effect on seed germination at LD50 or even LD99 . The utilization of such nanoformulations might open up a new avenue for ecofriendly pest control that is not damaging to humans or the environment, as well as a growing agricultural economy. PRACTICAL APPLICATION: The loss of cereals in postharvesting is one of the major challenges in the world because up to 50% of harvested grains might be destroyed. The intensive usage of chemicals caused harmful effects on humans and the environment. Thus, we prepared rosemary and black seed nanoemulsions and applied them for the grain weevil, S. granarius, control. The results showed superior toxicological efficacy without any effects on seed germination compared with their native oils. Such green strategy could be used instead of chemical insecticides to be environmentally safe for animals and humans.

Emotional mental imagery in alexithymic individuals as reflected in co-speech gesture

Nucleation is a key step in preventing gas hydrate formation during oil and gas production. Oil can sharply affect the hydrate nucleation with changing the activity of nucleation centers (mainly at the water–oil interface) over time. The spontaneous emulsification of water-in-oil emulsions in the course of aging can lead to a decrease in the size of water drops and, consequently, facilitate the hydrate nucleation and alter hydrate mitigation during the shut-in period

Nanoemulsions Containing Megestrol Acetate: Development, Characterization, and Stability Evaluation.

Many active pharmaceutical ingredients (API) are poorly soluble in water and their low oral bioavailability is a major hindrance to their potential use. Megestrol acetate (MGA) is insoluble in water and its oral absorption is limited and considerably affected by food. Nanoemulsions (NEs) can be used as effective oral drug delivery systems where the hydrophobic API is loaded into the oil phase. In this study, MGA-loaded NEs were prepared based on the spontaneous emulsification technique. The effects of different excipients such as ethanol, Tween 80, Lipoid E80, and medium-chain triglyceride (MCT) on the NEs characterization were investigated. The experimental results indicated that optimum MGA-loaded NEs (F20) were nanometer-sized droplets (166.9 ± 3.0 nm) with negative zeta potential (-12.2 ± 1.1 mV). The effect of polyvinylpyrrolidone (PVP) on characteristic properties of F20 was also evaluated. On the selected NEs, in vitro dissolution tests and stability studies in various mediums and storage conditions were performed. The encapsulation efficiency of NEs were > 99%. The overall droplet size of F20 and PVP-2 (PVP-coated NEs) remained relatively stable as the pH changed from 1.2 to 6.8. It was determined that F20 and PVP-2 remained stable at 4°C until 12 weeks and had higher cytotoxicity on MCF-7 cells. To conclude, droplet size, surface charge, and stability are important properties for NEs to have sufficient effectiveness. In this study, alternative oral NEs of low-solubility drug MGA were developed considering the above features.

Time-dependent nucleation of methane hydrate in a water-in-oil emulsion: effect of water redistribution

Nucleation is a key step in preventing gas hydrate formation during oil and gas production. Oil can sharply affect the hydrate nucleation with changing the activity of nucleation centers (mainly at the water–oil interface) over time. The spontaneous emulsification of water-in-oil emulsions in the course of aging can lead to a decrease in the size of water drops and, consequently, facilitate the hydrate nucleation and alter hydrate mitigation during the shut-in period

Emulsion gels loaded with pancreatic lipase: Preparation from spontaneously made emulsions and assessment of the rheological, microscopic and cargo release properties

Emulsion gels are solidified emulsions, which can be used for delivery of both hydrophilic and lipophilic substances. In this research, at first fish oil-in-water (O/W; 10% w/w) emulsions were prepared through the spontaneous emulsification technique. As emulsifier, a blend of the small-molecule surfactant tween 80, and either low-acyl (LaG) or high-acyl (HaG) gellan was used. For making fully stable (100% stability index) emulsions, a 10-fold higher concentration of LaG than HaG in the emulsion aqueous phase was required. The difference in gellan concentration resulted in a bigger mean drop size, as well as lesser consistency coefficient and yield stress for HaG emulsion than LaG emulsion.Subsequently, the fully stable HaG and LaG emulsions were gelled by CaCl2 addition. LaG emulsion gel was self-supporting and had a dense microstructure (as observed by electron microscopy), whereas HaG emulsion gel was not self-supporting. Loading lipase into the emulsions before ionotropic gelation did not lead to unacceptable acid values for fish oil during the emulsion gels storage.When the lipase-loaded fish O/W emulsion gels were immersed in an acid solution which imitated the gastric fluid (yet without digestive enzymes) oil droplets flocculated (as observed by confocal microscopy). The acid immersion also increased the dynamic moduli of the gels. Lipase was not released into the surrounding acid solution from LaG emulsion gel. A subsequent immersion within an alkaline solution imitating the small intestine fluid (yet without digestive enzymes) reduced the dynamic moduli of both kinds of emulsion gels. The alkaline immersion also caused extensive crack propagation in LaG emulsion gel network, which was found associated with diminished value of tan δ (Gʹʹ/Gʹ) as an index of gel energy dissipation. Lipase was released form LaG emulsion gel into the alkaline solution, however, it took a remarkable period of time to begin.

Interfacial Self-Assembly of Amphiphilic Core-Shell Bottlebrush Block Copolymers Toward Responsive Photonic Balls Bearing Ionic Channels.

Photonic balls can be facilely obtained through interfacial self-assembly of amphiphilic bottlebrush block polymers (BBCPs) within a water-in-oil-in-water (w/o/w) multiple emulsion system, and polystyrene (PS) has been employed as the skeleton of the balls showing no responsive properties. Here, the design and synthesis of core-shell BBCPs are demonstrated with a poly(tert-butyl acrylate)-block-polystyrene (PtBA-b-PS) block copolymer as the hydrophobic side chains and poly(ethylene glycol) as the hydrophilic block. Interfacial self-assembly of the core-shell BBCPs within shrinking droplets produces porous microspheres with full-spectrum structural colors through an organized spontaneous emulsification process. The PtBA core wrapped by PS in the skeleton of the balls can be converted into polyacrylic acid (PAA) forming an ionic channel responsive to pH variations. Consequently, the hydrolyzed photonic balls show different colors under different pH conditions dependent on varying degrees of ionization and hydration of the PAA channel. Reflected colors can be verified using an optical spectrometer, providing an effective strategy for precise pH indication.

Fabrication of nanoemulsion delivery system with high bioaccessibility of carotenoids from Lycium barbarum by spontaneous emulsification.

The interest in incorporating carotenoids into foods and beverages is growing due to their potential health benefits. However, the poor water solubility and low bioavailability of carotenoids are still challenges in food application. This work aimed to study the influence of system composition and preparation conditions on the physical properties of carotenoids‐loaded nanoemulsions prepared by spontaneous emulsification. Furthermore, the bioaccessibility of carotenoids in the nanoemulsions was evaluated. The nanoemulsions with the smallest droplet size were produced when the ratio of Span 80:Tween 80 was 1.5:8.5. The droplet size increased slightly with the increase of organic phase content (24%–40%). The droplet size decreased gradually with the increase of stirring speed (200–1000 rpm (revolutions per minute)). The ratio of mixed surfactants and surfactant‐to‐oil ratio (SOR) had an appreciable impact on the droplet size. Carotenoids‐loaded nanoemulsions with small mean droplet size (d < 50 nm) could be prepared with the optimized conditions. The initial digestion rate decreased as the SOR increased. The bioaccessibility could reach up to about 80% at SOR=2–5 in vitro digestion. These results have important implications for the design of effective delivery systems to encapsulate carotenoids and other lipophilic bioactive components in food applications.

Evaluating some Essential Oils-Based and Coconut Oil Nanoemulgels for the Management of Rheumatoid Arthritis

Essential oil-based and coconut oil nanoemulgels were formulated, and their anti-arthritic effect was evaluated. Nanoemulsions of lemon, ginger, turmeric, and coconut oil were formed by spontaneous emulsification. Nanoemulgels were obtained using 1 % of carboxymethylcellulose and carbopol. Characterizations included pH, transmittance, viscosity, conductivity, spreadability, and droplet size. Stability studies were performed. Arthritis was induced in Wister rats by injecting 0.1 ml formaldehyde (2 % v/v) into the sub plantar region. Paw volumes and thickness were measured for 28 days. Particles were nanosized with polydispersity indices ranging from 0.21 to 0.75. Formulations had pH of 4.96 to 6.81. Transmittances ranged from 0.02 to 95.6 %. Viscosities ranged from 308.3 to 1807 mPaS. Nanoemulgels were more stable at 25 ± 2 ºC. Anti-arthritic evaluations showed that ginger and lemon nanoemulgels exhibited higher and similar percentage inhibition patterns from days 7 to 28. Only ginger nanoemulgel reached basal paw values on day 28. Analysis of variance showed statistically significant differences (p&lt; 0.05) in results obtained on day 7 between Voltaren® and the lemon, turmeric, and coconut groups, while on day 21, there were also significant differences (p&lt;0.05) between the Voltaren® group and the ginger and coconut groups. Ginger nanoemulgel was most effective in treating rheumatoid arthritis.

Nano Matrix Soft Confectionary for Oral Supplementation of Vitamin D: Stability and Sensory Analysis.

Vitamin D deficiency distresses nearly 50% of the population globally and multiple studies have highlighted the association of Vitamin D with a number of clinical manifestations, including musculoskeletal, cardiovascular, cerebrovascular, and neurological disorders. In the current study, vitamin D oil-in-water (O/W) nanoemulsions were developed and incorporated in edible gummies to enhance bioavailability, stability, and patient compliance. The spontaneous emulsification method was employed to produce a nano-emulsion using corn oil with tween 20 and lecithin as emulsifiers. Optimization was carried out using pseudo-ternary phase diagrams and the average particle size and polydispersity index (PDI) of the optimized nanoemulsion were found to be 118.6 ± 4.3 nm and 0.11 ± 0.30, respectively. HPLC stability analysis demonstrated that the nano-emulsion prevented the degradation and it retained more than 97% of active vitamin D over 15 days compared to 94.5% in oil solution. Similar results were obtained over further storage analysis. Vitamin D gummies based on emulsion-based gelled matrices were then developed using gelatin as hydrocolloid and varying quantities of corn oil. Texture analysis revealed that gummies formulated with 10% corn oil had the optimum hardness of 3095.6 ± 201.7 g on the first day which remained consistent on day 45 with similar values of 3594.4 ± 210.6 g. Sensory evaluation by 19 judges using the nine-point hedonic scale highlighted that the taste and overall acceptance of formulated gummies did not change significantly (p > 0.05) over 45 days storage. This study suggested that nanoemulsions consistently prevent the environmental degradation of vitamin D, already known to offer protection in GI by providing sustained intestinal release and enhancing overall bioavailability. Soft chewable matrices were easy to chew and swallow, and they provided greater patient compliance.

Fabrication of edible solid lipid nanoparticle from beeswax/propolis wax by spontaneous emulsification: Optimization, characterization and stability

In the current study, the production and characterization of novel solid lipid nanoparticles (SLNs) using safe/low-cost natural beeswax (BW) and propolis wax (PW) and by the simple and inexpensive assay of spontaneous emulsification were studied. To fabricate SLNs, the optimum levels of surfactant/oil ratio (SOR), stirring speed, and time were obtained based on minimum particle size (PS) and polydispersity index (PDI). Therefore, the optimal conditions to produce PW and BW nanoparticles were SOR of 1.26 and 2 under stirring speed of 1050 rpm for 20 min, leading to PS of 21.9 and 23.2 nm, respectively. The contact angle of 73.7° and 62.9° for BW and PW SLNs respectively, showed suitable hydrophilicity to stabilize oil-in-water (O/W) Pickering emulsions. Temperatures over 70 °C led to a drastic increment of PS in both types of SLNs. Upon nanoparticles drying, the utilization of cryoprotectants could cause less aggregation and better reconstitution.

Self-Assembly of Polystyrene-b-poly(2-vinylpyridine)/Chloroauric Acid at the Liquid/Liquid Interface.

The self-assembly of polystyrene-block-poly(2-vinylpyridine) at the liquid/liquid interface has been systematically investigated to develop a series of primary morphologies of the aggregates. The block copolymers self-assembled into large areas of nanodot arrays, parallel nanostrands, layered films, parallel nanobelts, honeycomb monolayers, and foams by reacting with chloroauric acid, depending on the molecular structure of the block copolymers and the amount of chloroauric acid. The formation of the first four ordered structures resulted from interfacial adsorption and self-assembly, and nucleation and epitaxial growth. The latter two structures were attributed to the water hole templating effect and spontaneous interfacial emulsification, respectively. This work provides insight into the self-assembly behavior of block copolymers at the interface and provides a facile approach for fabricating functional structures.

Continuous Nanoprecipitation of Polycaprolactone in Additively Manufactured Micromixers.

The polymeric ouzo effect is an energy-efficient and robust method to create nanoparticles with biologically degradable polymers. Usually, a discontinuous or semi-continuous process is employed due to its low technical effort and the fact that the amount of dispersions needed in a laboratory is relatively small. However, the number of particles produced in this method is not enough to make this process economically feasible. Therefore, it is necessary to improve the productivity of the process and create a controllable and robust continuous process with the potential to control parameters, such as the particle size or surface properties. In this study, nanoparticles were formulated from polycaprolactone (PCL) in a continuous process using additively manufactured micromixers. The main goal was to be able to exert control on the particle parameters in terms of size and zeta potential. The results showed that particle size could be adjusted in the range of 130 to 465 nm by using different flow rates of the organic and aqueous phase and varying concentrations of PCL dissolved in the organic phase. Particle surface charge was successfully shifted from a slightly negative potential of −14.1 mV to a negative, positive, or neutral value applying the appropriate surfactant. In summary, a continuous process of nanoprecipitation not only improves the cost of the method, but furthermore increases the control over the particle’s parameters.

Spontaneous Emulsions: Adjusting Spontaneity and Phase Behavior by Hydrophilic-Lipophilic Difference-Guided Surfactant, Salt, and Oil Selection.

Spontaneous emulsion behavior has been difficult to predict and could be influenced by many variables including salinity, temperature, and chemical composition of the oil and surfactant. In this work, the hydrophilic-lipophilic difference (HLD) framework was used to predict the formation of spontaneous emulsions using a mixture of Span-80 and SLES surfactants. The spontaneity and emulsion behavior of different systems were modeled by estimating the HLDmix. The influence of surfactant ratio, salinity, and oil type was investigated. Spontaneous emulsification could only be observed when the HLDmix was between -0.96 and 1.04. Within this range, a negative HLDmix resulted in a greater spontaneity to form o/w emulsion, and a w/o emulsion was more likely to form when the HLDmix was positive. When the HLDmix was close to 0 (between -0.22 and 0.56 in our systems), emulsions were formed in both the oil and aqueous phases with high spontaneity. A combined effect of ultralow interfacial tension, Span-80 micelle swelling, and interfacial turbulence due to Marangoni effects is likely the main mechanism of the spontaneous emulsification observed in this study. A synergistic reduction in interfacial tension was observed between Span-80 and SLES (<1 mN/m). When the HLD of the system was close to 0, a bicontinuous emulsion phase was formed at the oil-water interface. The bicontinuous emulsion broke-up over time due to the ultralow interfacial tension and interfacial turbulence, forming dispersed oil and water droplets. Results from this work provide a practical method to suggest what surfactant composition, salinity, and oil type could promote (or eliminate) the conditions favorable for spontaneous emulsification.

Study of the spontaneous nano-emulsification process with different octadecyl succinic anhydride derivatives

Three new amphiphilic molecules were synthetized on a basis of a common monomer, octadecyl succinic anhydride (OSA), on which were grafted different PEGylated hydrophilic polar head. The objective of this study is to investigate a potential relationship between the chemical structure of the surfactant, and the efficiency to generate nano-emulsions through the spontaneous nano-emulsification method. Beyond the innovative synthesis and comparison of these amphiphiles, a comprehensive comparison is suggested, comparing size distribution and polydispersity for the different composition parameters, as well making a bridge with critical micelle concentration and hydrophile lipophile balance (HLB). Using OSA monomeric entity as common hydrophobic moiety, the variations in the surfactant molecules were done on the hydrophilic moiety, through the addition of one or two Jeffamine chains in different configurations, so-called C18⊖-PEG, C18-PEG and C18-PEG2. The results disclosed that C18⊖-PEG allows producing smallest size distribution and lowest PDI values. Moreover, C18⊖-PEG presents the highest critical micellar concentration, linked to a higher hydrophilicity of the molecule. This impacts the balance between surfactant affinity for oil and aqueous phases, a point probably related to the spontaneous emulsification efficiency. A last part of the study regarded the optimization of the emulsification efficiency, through a systematic study in ternary composition map, to disclosed that the best conditions are included in the lower surfactant concentrations, for water and oil contents higher and lower than 50%, respectively. The main idea behind this study was to bring further insights into the unclear relationship between the chemical structure of nonionic surfactants, and the efficiency of the emulsification by spontaneous low-energy method.

Physicochemical and stability profile of castor oil emulsions stabilized using natural and synthetic emulsifiers

Background: The quality and stability of castor oil emulsions may be influenced by the type and amount of its constituent emulsifiers. To our knowledge, the emulsifying potential of single, double, and triple-emulsifier systems comprising of Tween 20, acacia gum and methyl cellulose have never been compared. The aim of the work was to formulate castor oil emulsions stabilized using natural and/or synthetic emulsifying agents and evaluate their organoleptic, physicochemical, and stability profiles. Methods: Six types of emulsions were prepared using the spontaneous emulsification method, and characterised in terms of their physical properties; centrifugation analysis, and real-time stability profile at 25 ℃ and 40 ℃ for 90 days. Results: FT-IR analysis suggested that castor oil was compatible with all the studied emulsifiers. Tween 20-stabilised formulation (F2) and acacia gum/methyl cellulose-based samples (F5) exhibited unacceptable organoleptic attributes and/or physical properties. The physical properties of the remaining castor oil macroemulsions were satisfactory: pH (6.2 to 7.0); electrical conductivity (2253-4557 µS/cm); spreadability (0.7-2.1 cm); oil globule size (2.73-3.74 µm), and creaming index (9-18 %). The emulsions exhibited varying degree of instability over time and with elevated temperatures. The most promising emulsion was acacia gum/methyl cellulose/tween 20-stabilised sample F7: pH: 6.9, electrical conductivity: 4557 µS/cm, spreadability: 1.37 cm, oil globule size: 3.74 µm, creaming index: 9 %, and satisfactory stability profile at 25 °C and 40 °C. Conclusion: Sample F7 may serve as cream base for dermal and transdermal delivery of active pharmaceutical ingredients intended to treat various local skin problems and systemic diseases.