Higher Surfactant Concentrations Research Articles

Digestion of surfactants does not affect their ability to inhibit P-gp-mediated transport in vitro

While various non-ionic surfactants at low concentrations have been shown to increase the transport of P-gp substrates in vitro, in vivo studies in rats have shown that a higher surfactant concentration is needed to increase the oral absorption of e.g. the P-gp substrates digoxin and etoposide. The aim of the present study was to investigate if intestinal digestion of surfactants could be the reason for this deviation between in vitro and in vivo data. Therefore, Kolliphor EL, Brij-L23, Labrasol and polysorbate 20 were investigated for their ability to inhibit P-gp and increase digoxin absorption in vitro. Transport studies were performed in Caco-2 cells, while P-gp inhibition and cell viability assays were performed in MDCKII-MDR1 cells. Polysorbate 20, Kolliphor EL and Brij-L23 increased absorptive transport and decreased secretory digoxin transport in Caco-2 cells, whereas only polysorbate 20 and Brij-L23 showed P-gp inhibiting properties in the MDCKII-MDR1 cells. Polysorbate 20 and Brij-L23 were chosen for in vitro digestion prior to transport- or P-gp inhibiting assays. Brij-L23 was not digestible, whereas polysorbate 20 reached a degree of digestion around 40%. Neither of the two surfactants showed any significant difference in their ability to affect absorptive or secretory transport of digoxin after pre-digestion. Furthermore, the P-gp inhibiting effects of polysorbate 20 were not decreased significantly. In conclusion, the mechanism behind the non-ionic surfactant mediated in vitro P-gp inhibition seemed independent of the intestinal digestion and the results presented here did not suggest it to be the cause of the observed discrepancy between in vitro and in vivo.

Development of a Quantitative Analysis Method for Fragrances in a Sample Containing High Concentrations of Surfactants (Part I) – Fabric Softeners –

Development of a Quantitative Analysis Method for Fragrances in a Sample Containing High Concentrations of Surfactants (Part I) – Fabric Softeners –

Bubble size distribution and turbulence characterization in a bubbly flow in the presence of surfactant

This study aimed to quantify the less explored complex multiphase hydrodynamics of a bubble swarm in the presence of surfactant which is the key to flotation process widely used in the resources and environmental engineering applications.Experiments were conducted in a rectangular column (cross-section: 100 mm × 100 mm) in batch mode by varying the gas flux (0.02 to and 0.08 cm/s) in the presence of an anionic surfactant sodium dodecyl sulphate (5 to 15 ppm). High-speed imaging was then used to visualise the unsteady bubble plume dispersion behaviour and estimate the bubble size distribution (BSD) which showed a reduction in the mean bubble size with the increasing gas flux and surfactant concentration.Next, particle image velocimetry (PIV) was utilised to measure the instantaneous velocity field which was used to determine the turbulence characteristics. It was shown that the bubble plume contributes to significant anisotropy in the flow field which increased in the higher surfactant concentration and gas flux cases. The energy containing turbulence length scale was characterized by the integral length scale, which was observed to increase linearly with both the gas flux and surfactant concentration. Also, the local turbulence energy dissipation rate exhibited a strong linear correlation with the bubble surface area flux parameter. In the presence of surfactant, the turbulence energy spectrum of the system exhibited a less steep slope in the inertial subrange regime compared to the Kolmogorov −5/3 slope. The spectrum also showed a leftward shift indicating energy addition to the larger turbulence length scales which was reflected in the formation of large recirculation zones around the bubble plume.

Identification of Surfactant Impact on a Monoclonal Antibody Characterization via HPLC-Separation Based and Biophysical Methods.

Surfactants, including polysorbates and poloxamers, play a crucial role in the formulation of therapeutic proteins by acting as solubilizing and stabilizing agents. They help prevent protein aggregation and adsorption, thereby enhancing the stability of drug substance and products., However, it is important to note that utilizing high concentrations of surfactants in protein formulations can present significant analytical challenges, which can ultimately affect the product characterization. In our study, we specifically investigated the impact of elevated surfactant concentrations on the characterization of monoclonal antibodies. We employed various analytical techniques including size-exclusion chromatography (SEC), capillary electrophoresis (CE-SDS), a cell based functional assay, and biophysical characterization. The findings of our study indicate that higher levels of Polysorbate 80 (PS-80) have adverse effects on the measured purity, biological activity, and biophysical characterization of biologic samples. Specifically, the elevated levels of PS-80 cause analytical interferences, which can significantly impact the accuracy and reliability of analytical studies. Our study results highlight a significant risk in analytical investigations, especially in studies involving the isolation and characterization of impurities. It is important to be cautious of surfactant concentrations, as they can become more concentrated during common sample manipulations like buffer exchange. Indeed, the research presented in this work emphasizes the necessity to evaluate the impact on analytical assays when there are substantial alternations in the matrix composition. By doing so, valuable insights can be gained regarding potential challenges associated with assay development and characterization of biologics with complex formulations.

Conductometric and spectral analyses of dye-surfactant interactions between indigo carmine and N-alkyltrimethylammonium chloride

The electrical conductivity technique was used to investigate the critical micelle concentration (CMC) of cationic surfactants N-alkyltrimethylammonium chloride (CnTAC; n = 12, 14, 16, and 18). Meanwhile, the interaction between CnTAC and indigo carmine (IC, an anionic dye) was studied using spectrophotometry. Employing the Benesi-Hildebrand and Scott equations, the binding constant (Kb) of IC to the cationic micelles was determined. Calculation of the Gibbs free energy (ΔG) revealed the tendency of IC to bind to micelles. The association between IC and CnTAC clearly depends on the CnTAC concentration: a lower surfactant concentration disrupts the IC-CnTAC complex and decreases IC adsorption, while a higher surfactant concentration has the opposite effect. The alkyl chain length of CnTAC was also found to affect the CMC, Kb, and thermodynamic parameters. A longer alkyl chain reduces the CMC and ΔG and increases Kb, leading to increased solubilization and high spontaneity of the dye. The binding of IC to micelles is ranked as C12TAC < C14TAC < C16TAC < C18TAC.

Experimental study on heat transfer performance enhancement of pulsating heat pipes induced by surfactants

Pulsating heat pipe (PHP) is considered as a promising technique to address the thermal dissipation issues in micro-electronic devices, but its heat transfer performance needs to be further enhanced urgently. In this study, the PHP comprehensive performance experimental system was established. Then, the influence of surfactant sodium dodecyl sulfate (SDS) aqueous solution on the heat transfer performance of PHP was experimentally investigated and the visualization of PHP with surfactant was also accomplished. Additionally, based on Marangoni effect and surface tension, a comprehensive analysis was conducted on the impact mechanism of surfactants on PHP. The experimental results indicated that the oscillatory disturbance of the liquid slug inside the PHP is enhanced by the addition of SDS, and the resulting pressure imbalance and temperature difference enhance the directional flow of the working fluid. Meanwhile, under the operating conditions of 30 W working thermal power and the solution concentration of 0.001 wt%, the thermal resistance of PHP was reduced by 30.7 % compared with that of deionized water (DI water). This indicated that the working fluid with low concentration SDS could increase the area of liquid film and reduce the thermal resistance, which is induced by the surface tension and Marangoni effect due to the uneven distribution of surfactants. However, the thermal resistance of PHP with the SDS concentration of 0.2 wt% is higher than that of DI. This means that high concentration of SDS would deteriorate the startup characteristics and the heat transfer performance of PHP. Therefore, high concentrations of surfactants should be avoided from practical application of PHP.

Surfactant-laden liquid thread breakup driven by thermal fluctuations

The breakup of liquid threads into droplets is crucial in various applications, such as nanoprinting, nanomanufacturing, and inkjet printing, where a detailed understanding of the thinning neck dynamics allows for a precise droplet control. Here, the role of surfactant in the breakup process is studied by many-body dissipative particle dynamics, in particular, the various regime transitions and thread profiles, shedding light on molecular-level intricacies of this process hitherto inaccessible to continuum theory and experiments. Moreover, the role of surfactant in the most unstable perturbation, the formed droplet size, and surfactant distributions have been unraveled. As surfactant concentration rises, both the wavelength and time to breakup steadily increase due to the lowering of surface tension below the critical micelle concentration (CMC) and viscous effects introduced by micelles above the CMC. These changes prior to the breakup lead to larger droplets being formed in cases with higher surfactant concentration. We also compared the thinning dynamics to existing theoretical predictions, revealing that the surfactant-laden breakup starts at the inertial regime and transitions into the thermal fluctuation regime when the concentration is increased. Thus, we illuminate the hitherto poorly investigated and intricate breakup process of surfactant-laden liquid threads driven by thermal fluctuations, contributing to a deeper understanding of this process at molecular scales.

Salt-acid-surfactant synergistic effects on interfacial characteristics of water/oil systems: A molecular dynamics simulation study

Low salinity water injection with surfactants is one of the standard approaches in enhanced oil recovery (EOR). This method relies on the interaction of surfactants and ions at oil/water interfaces to reduce the interfacial tensions. However, the details of the mechanisms governing the synergistic effects of these components are still debatable. In this study, molecular dynamic (MD) simulations have been employed to investigate the challenging interactions of chemicals and saline water at a molecular scale. The model oil phase used in this study was defined as a mixture of toluene and decane. In addition, the synergistic materials are NaCl, sodium dodecyl ethoxy sulfate (AES), and decanoic acid.The results of density profiles, planar distribution maps, and PMF calculations imply that the acid molecules in the oil phase act as surfactants and form micelles. A few water molecules are also transferred to the oil phase to form water-acid micelles at high surfactant concentrations. Consequently, the number of acid components in the interfacial area is decreased; hence, the IFT reduction is alleviated. The results showed that micelle formation was decreased by adding ions to the aqueous phase. RDF profiles indicate that surfactant-acid interaction improves by adding ions to the water phase. The higher surfactant-acid interactions keep the polar hydrocarbon molecules near the interface and prevent them from moving to the hydrocarbon phase. This study also highlights the vital role of surfactant-acid interactions in the arrangements and orientations of surface-active materials. Orientation analysis indicates that salts in water and hydrophobic acids synergize to orient surfactants parallel to the interface. These facts signify that the surfactant-acid interaction is one of the main factors that critically affect the water–oil interfacial behavior.

Stability of Viscoelastic Solutions: BrijL4 and Sodium Cholate Mixtures with Metal Ions Across a Broad pH and Temperature Range.

The impact of pH, temperature, and metal ions on the rheological and interfacial properties of aqueous mixed surfactant solutions composed of anionic NaC (sodium cholate) and nonionic BrijL4 [polyoxyethylene (4) lauryl ether] surfactants has been investigated. The various compound systems were analyzed, considering variations in each selected factor. The results highlight the unique characteristics of the BrijL4/NaC mixture, suggesting its potential as a viable alternative to other existing surfactants. The synergistic effect between BrijL4 and NaC significantly reduces the critical micelle concentration (CMC) and improves the wetting properties on hydrophobic surfaces, surpassing those of single-component solutions. Additionally, sodium, calcium, and magnesium ions enhance surface wetting and decrease the CMC. Besides, the BrijL4/NaC solutions exhibit viscoelastic fluid behavior at higher surfactant concentrations. These viscoelastic BrijL4/NaC solutions demonstrate stability over various pH and temperature variations, exhibiting lower flow activation and scission energy values than those of other viscoelastic surfactant solutions. Notably, the BrijL4/NaC mixture has potential applications in gel-based foliar fertilizers and drug delivery systems. Furthermore, the rheological studies examine the impact of humic acid on the rheological properties of BrijL4/NaC mixture solutions, revealing that incorporating additional humic acids can achieve stable rheological properties.

Nanoemulsions Stable against Ostwald Ripening.

Ostwald ripening, the dominant mechanism of droplet size growth for an O/W nanoemulsion at high surfactant concentrations, depends on micelles in the water phase and high aqueous solubility of oil, especially for spontaneously formed nanoemulsions. In our study, O/W nanoemulsions were formed spontaneously by mixing a water phase with an oil phase containing fatty alcohol polyoxypropylene polyoxyethylene ether (APE). By monitoring periodically the droplet size of the nanoemulsions via dynamic light scattering, we demonstrated that the formed O/W nanoemulsions are stable against Ostwald ripening, i.e., droplet growth. In contrast, the nanoemulsion droplets grew with the addition of micelles, demonstrating the pivotal role of the presence of micelles in the water phase in the occurrence of Ostwald ripening. The influence of the initial phase of APE, the oil or water phase in which APE is present, on the micelle formation is discussed by the partition coefficient and interfacial adsorption of APE between the oil and water phase using a surface and interfacial tensiometer. In addition, the spontaneously formed O/W nanoemulsion, which is stable against Ostwald ripening, can be used as a nanocarrier for the delivery of water-insoluble pesticides. These results provide a novel approach for the preparation of stable nanoemulsions and contribute to elucidating the mechanism of instability of nanoemulsions.

Experimental study on the synergistic dust reduction of MNBs and surfactants

Spray dust suppression is a primary technological method for controlling coal mine dust. To enhance the wetting and adhesion of droplets to dust particles and improve the efficiency of spray dust suppression, a method of synergistic dust reduction by micro-nano bubbles (MNBs) and surfactants is proposed. This research focuses on MNBs, three different types of surfactants, and low-wetting anthracite coal. Experimental analysis is conducted to investigate the interaction between surfactants and MNBs in solution. The wetting capability of dust particles by the mixed solution of MNBs and surfactants is studied. Additionally, a spray dust suppression experimental platform is employed to compare the dust reduction efficiency of different types of surfactants in synergy with MNBs. The experimental results indicate that surfactants facilitate the generation of nanoscale bubbles, reduce the average diameter of MNBs, and the charge carried by surfactant molecules affects the potential of MNBs. Anionic surfactants decrease the bubble potential, while cationic surfactants elevate it, with non-ionic surfactants having a minimal impact on bubble potential. The presence of MNBs can temporarily reduce the surface tension of a surfactant solution, bringing it to the surface tension at the critical micelle concentration (CMC) but cannot surpass the surface tension beyond the CMC. The addition of low-concentration surfactant solutions to bubbles decreases the contact angle between dust particles and coal dust, while high-concentration surfactant solutions have the opposite effect. In general, the combined use of MNBs and surfactants is beneficial for improving spray dust suppression efficiency. However, extremely high surfactant concentrations lead to an excessive absolute value of bubble potential, enhancing the stability between dust particles and reducing dust suppression efficiency.

Influence of High Surfactant Concentrations on the Morphology and Crystallinity of Electrodeposited Antimony and Bismuth Nanowires

Antimony and bismuth nanowires are excellent model systems to investigate the interplay of various size-dependent transport phenomena relevant for applications in thermoelectrics, spintronics, or catalysis. The properties of these nanowires can be significant influenced by size effects due to the large mean free path and Fermi wavelength of charge carriers and phonons. Since antimony and bismuth possess highly anisotropic Fermi surfaces, the transport is also strongly dependent on the crystallographic orientation. Therefore, it is very important to develop and control suitable electrodeposition processes that allow us to understand the nanowire growth and to accordingly adjust preferred orientation and morphology of the synthesized nanowires.The so called template route employed in the presented work allows to control number density, alignment, geometry, length and diameter of the nanowires. The electrolytes and plating processes influence crystallinity, crystal orientation, and morphology of the electrodeposited materials. Here, antimony and bismuth nanowires are grown by potentiostatic electrodeposition in polycarbonate etched ion-track membranes using SbCl3 and BiCl3 in aqueous electrolytes.In this talk, we will show the influence of the presence of nonionic and anionic surfactants in high concentrations in the electrolyte during the electrodeposition of Bi and Sb nanowires. The recorded current-time curves of the plating process will be presented. Systematic characterization of the nanowires by scanning- and transmission electron microscopy, and X-ray diffraction reveal a strong change in crystallinity as a function of surfactant concentration, which will be discussed in detail.

Producing superior oleofoams: Unraveling the impact of oil type, surfactant concentration, and production temperature on foam stability and functional characteristics

This study explores the impact of oil type, surfactant concentration, and production temperature on oleofoam properties. Oleofoams were prepared using different concentrations (5, 8, and 10 % w/w) of monoglyceride (MG) in olive, soybean, and sunflower oils at temperatures of 25 °C and 5 °C. The results indicate that higher surfactant concentrations and lower production temperatures enhance the stability, foamability, melting behavior, and hardness of the oleofoams, while minimizing oil drainage. Microscopic analysis reveals that lower production temperatures result in smaller bubble sizes in all oil blends which reduces oil loss and increases the hardness of the oleofoam. Also, oleofoams derived from different oils exhibit solid-like behavior. Among the oils studied, the oleofoam prepared with sunflower oil, at a concentration of 10 % MG and a production temperature of 5 °C, demonstrates superior properties. These findings provide valuable insights into optimizing oleofoam properties by controlling the oil type, surfactant concentration, and production temperature.

Surfactant-Aided Stabilization of Individual Carbon Nanotubes in Water around the Critical Micelle Concentration.

Surfactants are widely used to disperse single-walled carbon nanotubes (SWCNTs) and other nanomaterials for liquid-phase processing and characterization. Traditional techniques, however, demand high surfactant concentrations, often in the range of 1-2 wt/v% of the solution. Here, we show that optimal dispersion efficiency can be attained at substantially lower surfactant concentrations of approximately 0.08 wt/v%, near the critical micelle concentration. This unexpected observation is achieved by introducing "bare" nanotubes into water containing the anionic surfactant sodium deoxycholate (DOC) through a superacid-surfactant exchange process that eliminates the need for ultrasonication. Among the diverse ionic surfactants and charged biopolymers explored, DOC exhibits the highest dispersion efficiency, outperforming sodium cholate, a structurally similar bile salt surfactant containing just one additional oxygen atom compared to DOC. Employing all-atomistic molecular dynamics simulations, we unravel that the greater stabilization by DOC arises from its higher binding affinity to nanotubes and a substantially larger free energy barrier that resists nanotube rebundling. Further, we find that this barrier is nonelectrostatic in nature and does not obey the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal stability, underscoring the important role of nonelectrostatic dispersion and hydration interactions at the nanoscale, even in the case of ionic surfactants like DOC. These molecular insights advance our understanding of surfactant chemistry at the bare nanotube limit and suggest low-energy, surfactant-efficient solution processing of SWCNTs and potentially other nanomaterials.

Intensification of processes of biological wastewater treatment

Purification of urban wastewater traditionally takes place at biological treatment plants, which were built in the 60s and 70s of the last century and are still being operated in populated areas of Ukraine. Today's wastewater contains high concentrations of surfactants, organic compounds, biogenic substances and other pollutants from enterprises that exceed the permissible concentrations at the entrance to treatment plants, which leads to ineffective treatment in traditional biological treatment schemes. It was this fact that became one of the main reasons for exceeding concentrations of nitrogen and phosphorus compounds in water sources. Therefore, in order to intensify wastewater treatment, it is necessary to choose more effective methods of wastewater treatment and to design structures that will ensure their proper treatment. The work considers the microbiological processes that will take place in the proposed design of the bioreactor.

The potential emulsions of xanthan gum and Daucus carota macerated oil in functional textiles for skincare applications: Formulation, characterization, and performance evaluation

This study investigates the formulation and characterization of functional textiles with skin hydration properties by using Daucus carota macerated oil-based O/W emulsions. The key novelty lies in obtaining skin-hydrating textiles by using Daucus carota macerated oil as an active compound. Ten O/W emulsions were prepared by mixing in different ratios of Daucus carota macerated oil, xanthan gum, Tween 80, and water. The droplet morphology (size and shape) and the properties of the emulsion (pH, conductivity, turbidity, surface tension, contact angle) were investigated as a function of each constituent variation in the formulation, maintaining the others constant, to find the proper conditions to obtain stable and compatible with skin application o/w emulsions. Selected emulsions were tested for their biocompatibility and antimicrobial properties. The biocompatibility test shows that the high surfactant content is cytotoxic to NHDF cells, whereas emulsions with less surfactant content are biocompatible, irrespective of the Daucus carota macerated oil content. The emulsion skincare effects were evidenced by skin hydration and antimicrobial analyses. The obtained results suggest that these bioactive emulsions have sufficient potential to be used in skincare finishes to textiles by applying them on a cellulosic fabric obtaining new functional textiles with skin hydration properties and good comfort indexes (hygroscopicity, air, and vapor permeability). This study opens new perspectives in the field of skincare textiles by exploring the moisturizing potential of Daucus carota macerated oil emulsions in obtaining functional supports with skin hydration properties. The results provide evidence that the obtained functional textiles show better skin hydration compared to the case with direct application of the emulsion on the skin. Thus, the textile support plays a significant role in creating an occlusive barrier that helps retain moisture and prevents the loss of water from the skin's surface. Consequently, skincare textiles could represent an excellent choice for skin hydration.

Free-energy-based lattice Boltzmann model for emulsions with soluble surfactant

We propose a diffuse interface model to simulate a system of two immiscible liquids with surfactant. This model is based on a modified Ginzburg-Landau free energy functional to account for non-ionic soluble surfactants and couples the Navier-Stokes equations with two Cahn-Hilliard transport equations to represent immiscible fluids and surfactant concentration. The governing equations are solved using a lattice Boltzmann framework. The proposed model is validated for Langmuir and Frumkin adsorption isotherms when applied to simulate a planar interface and a spherical drop equilibration. The model ensures numerical stability and accurate results for low and high surfactant concentrations, and the diffuse interface thickness remains constant even for high surfactant loads. The model also allows achieving a surface tension reduction of 45-50% compared to the clean system, even at low surfactant concentrations. The appropriate surfactant mobility and solubility values are recommended for different values of the strength of nonlinear surfactant coupling.

Precise particle size control during spherical agglomeration of benzoic acid by modification of the bridging liquid phase using TWEEN 20

The interest in spherical agglomeration processes in the pharmaceutical industry is rising due to the possibility of direct tableting of Active Pharmaceutical Ingredients and enhancements in bulk powder properties translating into improved powder processability. While agglomerating needle-shaped particles into spheres offers numerous advantages, such as improved flowability, filterability, and particle density, achieving precise control over the particle size and shape of the agglomerates remains a significant challenge. More specifically, the obtained agglomerate size rarely reaches values below 500 μm, which is the desired size range for pharmaceutical applications. To address this challenge, the current research investigates the effectiveness of incorporating surfactants at varying concentrations as a means to control the particle size and shape of the resulting agglomerates. Reversed addition antisolvent crystallization experiments were performed in ethanol/water using benzoic acid as a model compound, followed by the addition of a bridging liquid (toluene), which wets and bridges the single crystals into agglomerates. To modify the interfacial tension between the two immiscible liquid phases, different concentrations of the tween 20 surfactant were used, leading to a range of interfacial tensions spanning from 0.50 to 16.38 × 10−3 N/m. Both crystallization and agglomeration processes were monitored in situ using in-process microscopy tools. The experimental results demonstrated that by adjusting the surfactant concentration and thus the corresponding interfacial tension of the bridging liquid, highly tunable agglomerate sizes were achieved, ranging from 160 μm to 4412 μm. A higher surfactant concentration is correlated with smaller agglomerates and is key to control the final agglomerate size. However, it should be noted that the introduction of surfactants in the spherical agglomeration process negatively impacted the agglomerate's strength. Nonetheless, this method remains a promising and innovative technique for controlling the final particle size during spherical agglomeration.

The aqueous processing of carbon nanofibers via cellulose nanocrystals as a green path towards e-textiles with n-type thermoelectric behaviour

Cellulose nanocrystals (CNCs) are a nanostructured biopolymer with unique properties, such as high strength and water stability. These properties make CNCs ideal for diverse applications, including dispersing agents for hydrophobic carbon nanomaterials in water. Specifically, carbon nanomaterials can be integrated into textiles to produce flexible electronic wearables with excellent performance. However, the necessary prerequisite of achieving stable liquid dispersions of these carbon nanomaterials, such as nanofibers (CNFs) typically involves the use of organic solvents or high concentrations of hazardous surfactants in water. Thus, in this study, for the first time, CNCs were successfully used to prepare CNFs aqueous dispersions, referred to as inks, at CNF concentrations up to 0.7 g L−1. As a proof of principle, these inks were then integrated into a cotton fabric using a facile dip coating and drying strategy, resulting in an e-textile with a negative Seebeck coefficient. Furthermore, a theoretical model was developed to describe the nonlinear Seebeck coefficient of the nanocomposite textile, shedding light on the physics governing the electrical conductivity and Seebeck coefficient over a temperature range from 30 °C to 100 °C. These promising results pave the way towards the development of environmentally friendly and durable CNF aqueous dispersions and wearable e-textiles.

Self-emulsifying drug delivery systems (SEDDS) disrupt the gut microbiota and trigger an intestinal inflammatory response in rats

Self-emulsifying drug delivery systems (i.e. SEDDS, SMEDDS and SNEDDS) are widely employed as solubility and bioavailability enhancing formulation strategies for poorly water-soluble drugs. Despite the capacity for SEDDS to effectively facilitate oral drug absorption, tolerability concerns exist due to the capacity for high concentrations of surfactants (typically present within SEDDS) to induce gastrointestinal toxicity and mucosal irritation. With new knowledge surrounding the role of the gut microbiota in modulating intestinal inflammation and mucosal injury, there is a clear need to determine the impact of SEDDS on the gut microbiota. The current study is the first of its kind to demonstrate the detrimental impact of SEDDS on the gut microbiota of Sprague-Dawley rats, following daily oral administration (100 mg/kg) for 21 days. SEDDS comprising a lipid phase (i.e. Type I, II and III formulations according to the Lipid Formulation Classification Scheme) induced significant changes to the composition and diversity of the gut microbiota, evidenced through a reduction in operational taxonomic units (OTUs) and alpha diversity (Shannon’s index), along with statistically significant shifts in beta diversity (according to PERMANOVA of multi-dimensional Bray-Curtis plots). Key signatures of gut microbiota dysbiosis correlated with the increased expression of pro-inflammatory cytokines within the jejunum, while mucosal injury was characterised by significant reductions in plasma citrulline levels, a validated biomarker of enterocyte mass and mucosal barrier integrity. These findings have potential clinical ramifications for chronically administered drugs that are formulated with SEDDS and stresses the need for further studies that investigate dose-dependent effects of SEDDS on the gastrointestinal microenvironment in a clinical setting.