Abstract Surfactants are in high demand across various industrial sectors. Edible oils are a renewable feedstock resource which has acquired increasing demand due to the environmentally-friendly alternatives t7o the petroleum-based products, with focus on sustainability and green chemistry principles. Renewable feedstock not only enhance biodegradability but also supports circular economy. The study deals with the synthesis of anionic surfactant from grapeseed oil which is a byproduct for the wine industry. It is rich in linoleic C18:2, oleic C18:1, palmitic C16 and stearic C18 fatty acids present in it. Anionic surfactant was synthesized via transesterification of grapeseed oil (GSO) and Sulfonation followed by sodium bisulphite (NaHSO 3 ) and Neutralization. The process yielded fatty acid methyl ester (FAME) and methyl ester sulfonates (MES), an anionic surfactant with good surface-active properties. Characterization included the successful initiation of sulfonate groups, examined by fourier transform infrared spectroscopy (FTIR) along with nuclear magnetic resonance (NMR), surface activity parameters like surface tension, foam height, critical micelle concentration (CMC), contact angle, active matter, moisture content, pH, and appearance was determined. This work confirms grapeseed oil as a potential raw material for eco-friendly anionic surfactant production, furnishing valuable prospects, applications in cosmetics and detergency and adaptable alternatives in the surfactant industry.
This research utilizes conductivity measurements to elucidate the temperature-induced aggregation of cetyltrimethylammonium bromide (CTAB) in combination with nafcillin sodium (NafNa), in addition to emphasizing the impact of urea and glucose on micellization. The addition of NafNa delayed the micellization of CTAB. Glucose, by establishing hydrogen bonds with water, renders the solvent less conducive for the hydrophobic tails of the CTAB surfactant, thereby elevating the CMC. Urea diminishes the hydrophobic action that promotes micellization by altering the water structure, hence increasing the CMC The interaction between CTAB and NafNa has been characterized employing physicochemical variables (counterion dissociation, alpha; and CMC) and thermodynamic parameters (entropy of micellization, Delta S 0 m ; Gibbs energy of micellization, Delta G 0 m ; and enthalpy of micellization, Delta H 0 m ). The spontaneity of micellization in the CTAB-NafNa system in both water and urea/glucose conditions is depicted by the negative Delta G 0 m results. Negative Delta S 0 m and Delta H 0 m values indicate the predominance of H-bonding, while positive values of Delta S 0 m and Delta H 0 m indicate hydrophobic interactions. The results offer critical understanding for scholars aiming to refine parameters, including temperature, concentration, and the incorporation of urea/glucose additives, to improve the effectiveness and durability of drug delivery systems.
This study aims to investigate the role of a non-ionic surfactant in controlling the growth, morphology, and structural properties of copper oxide (CuO) nanostructures synthesized via a sol-gel route. CuO nanoparticles were prepared using aqueous copper sulfate as the precursor and Tween 80 as a structure-directing and stabilizing agent, with systematic control of synthesis parameters followed by calcination to obtain crystalline products. The as-synthesized materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) to evaluate phase formation, chemical interactions, thermal stability, and surface morphology. The results confirm the formation of phase-pure monoclinic CuO with nanoscale crystallite sizes, as evidenced by sharp XRD reflections and Scherrer analysis. SEM observations reveal that Tween 80 effectively suppresses excessive agglomeration and promotes the formation of relatively uniform nanostructures with mixed spherical and polyhedral morphologies. FTIR and TGA analyses further demonstrate the presence of surfactant-nanoparticle interactions during synthesis and their complete removal upon calcination, resulting in thermally stable CuO nanostructures. Overall, the study demonstrates that Tween 80 plays a crucial role in regulating nucleation and growth processes, offering a straightforward and cost-effective approach for tailoring CuO nanostructures through surfactant-assisted sol-gel synthesis.
A simple, low-cost competitive assay for the determination of hexadecyltrimethylammonium bromide (CTAB) has been developed. This assay employs a specific type of color catcher sheet which can adsorb the cationic dye crystal violet. Solutions containing various amounts of cationic surfactant and constant amount of crystal violet were prepared and the dye was subsequently extracted using color catcher sheet. Digital images of the sheets with the adsorbed crystal violet were taken with a mobile phone; the image analysis of the photos was performed using Color Picker application. The values of several color spaces were collected. Specific values from RGB, CMY, XYZ and LAB color spaces were either directly or indirectly proportional to the concentration of CTAB in the analyzed samples. The described inexpensive, simple and elution free assay enables analysis of cationic surfactant in various solutions.
Extended surfactants (ESs), obtained by inserting an oligomeric oxypropylene segment often together with an oligomeric oxyethylene segment between the hydrophobic tail and an anionic polar headgroup, have attracted considerable interest for enhanced oil recovery (EOR) due to their high salinity tolerance and favorable synergistic interactions with conventional anionic surfactants used for EOR. Sulfated ESs, in particular, have been extensively studied and applied in combination with alkylbenzene sulfonates (ABS) and olefin sulfonates. However, the limited thermal stability of sulfate head groups restricts their application in high-temperature reservoirs. In this study, three ESs with identical hydrophobic tail and the same oxypropylene-oxyethylene chain but different hydrophilic head groups - sulfate, sulfonate, and carboxylate - were synthesized and characterized. The three ESs showed comparable CMC values and excellent salinity tolerance. The sulfonate- and carboxylate-based ESs remained stable for several weeks at 120 degrees C, whereas the ES with a sulfate end group was rapidly hydrolyzed. All ABS/ES formulations formed Winsor Type III microemulsions with similar solubilization ratios, although the ABS/carboxylate system exhibited lower optimum salinity than the other two systems. Coreflooding using Berea sandstone outcrops achieved a yield of 50-56 % of the original oil in place (OOIP) after waterflooding.
This study presented the synthesis, characterization, and functional evaluation of a novel family of zwitterionic Gemini surfactants using 2,3-dibromosuccinic acid as a unique difunctional spacer. This spacer effectively and consistently incorporated two amidoamine/alkyl dimethyl amine hydrophobes due to its strong polarity, reactivity, and symmetrical structure. 2,3-dibromosuccinic acid improves surface-active performance by adding ionic stability and structural rigidity. This study indicated that this is the first recorded application of 2,3-dibromosuccinic acid in the synthesis of novel Zwitterionic Gemini surfactants. The Gemini surfactants synthesized were characterized by FTIR, NMR, and Mass spectroscopy. They were synthesized from amidoamines based on fatty acids, such as lauric, caprylic/capric, and 2-ethylhexanoic acids, and dodecyldimethyl amine. The physicochemical properties, viz. surface tension, critical micelle concentration (CMC), C20 reduction, foaming behaviour, and wettability, were studied and compared with those of a commercial monomeric betaine. Application Properties like whiteness index, softness, and antistatic performance on polyester fibre and fabrics were also evaluated. These surfactants are found as effective as non-ionic surfactants, softening polyester fabric, reducing static electricity, and achieving remarkable foam stability when applied to textiles. This research work also highlights an innovative molecular design approach that utilizes 2,3-dibromosuccinic acid, paving the way for next-generation zwitterionic surfactants.
The effects of urea and sodium chloride (NaCl) on the binding behavior of the surfactant cetylpyridinium chloride (CPC) with the antihistamine drugs diphenhydramine hydrochloride (DPH) and cetirizine hydrochloride (CTZ) were investigated using conductivity measurement. The critical micelle concentration (CMC) values were determined by measuring conductivity changes in surfactant solutions and surfactant-antihistamine mixed systems at varying concentrations of urea and NaCl. To elucidate the mechanism by which urea and NaCl affect surfactant-antihistamine interactions, key parameters such as the slope of the conductivity curve and ion migration behavior were analyzed. The feasibility and driving force of micelle formation were evaluated by analyzing standard thermodynamic parameters. The negative value of Delta G m theta $\Delta {G}_{m}<^>{ heta }$ indicate that micelle formation in the studied system is spontaneous. Furthermore, the transfer thermodynamic parameters for CPC micelles in the presence of the drugs were calculated and discussed. This study holds significance for the design of drug formulations and for industrial processes involving surfactants and additives.
Nowadays, the pandemic events have brought vaccines back into the focus of scientific research. The adjuvants are extremely important for the effectiveness of vaccines. Research and development based on the modernization of ingredients enables the development of more effective adjuvants with a better risk-benefit ratio. In our study, we aimed to develop squalene-containing nanoemulsion adjuvants using modern surfactants. The ultras method was used to develop a squalene-based adjuvant. The size and zeta potential of the created nanoemulsion adjuvant systems and their stabilities were investigated by DLS techniques. Both in vitro and in vivo harmlessness were demonstrated. The immunoglobulin production-promoting effect (IgG and IgE) was tested. Using the ultrasound size reduction process, the achieved size range was less than 200 nm. The size and zeta potential of the preparation remain stable for several months without significant changes. The developed adjuvant was not toxic in Galleria mellonella larvae and in the fibroblast cell line. The formulation achieved similar IgG and IgE production to Addavax, with IgG and IgE levels two orders of magnitude higher after 45 days compared to the OVA dosing alone. In summary, we have successfully developed a modern tenside-containing squalene adjuvant.
Foam drainage agents are critical for boosting natural gas extraction efficiency by reducing gas well liquid accumulation, yet traditional ones lack sufficient corrosion inhibition, endangering wellbore infrastructure. This study aims to enhance their corrosion inhibition by adding hydrazine hydrate, developing an integrated system with both foam-generation and corrosion-protection functions. The optimized formulation is 0.1 % sodium alpha-olefin sulfonate (AOS) + 0.3 % dodecyl dimethyl betaine (BS-12) + 0.5 % hydrazine hydrate. It achieves a 92.59 % corrosion inhibition efficiency on Q235 steel, lowering the corrosion rate to 0.0076 mm/a. Electrochemical tests (potentiodynamic polarization, AC impedance) show the composite inhibitor mainly inhibits anodic reactions, with a significant positive shift in corrosion potential. The inhibitor's adsorption on the metal surface follows the Langmuir isotherm model (strong adsorption capacity), and the process is spontaneous (Gibbs free energy: -24 to -27.5 kJ/mol). Thermodynamic and kinetic analyses clarify the adsorption mechanism and inhibitor stability under different temperatures. This integrated agent has a synergistic effect on foam stabilization and corrosion inhibition, offering a promising solution to improve natural gas well operation efficiency and safety. It also contributes to developing multifunctional corrosion inhibitors for complex wellbore environments (high temperature, high salinity, methanol presence).
Foam dynamics of SLAt and SLGt (differing by one methylene group) were studied via dynamic foam analysis, rheology, and MD simulations. SLAt achieves optimal performance at pH 7.0: lowest surface tension (28.096 mN/m), rapid foaming, moderate foam volume (96.8 mL), large initial bubbles (4,444 & micro;m2), and high stability. SLGt peaks under weak alkalinity with greater volume (106.2 mL) and stability (tFLS 50 % = 503.1 s), but slower foaming, smaller bubbles, and coarsening susceptibility. Synergy with co-surfactants reveals: CAB boosts foam volume (115-117 mL), SMCT enhances lipid removal in sebum systems.MD simulations show SLGt adopts extended conformations with higher hydrophilicity, improving surface tension reduction. SMCT exhibits stronger hydrophobic interactions for lipid sequestration. Hydrogen bonds between primary/co-surfactants govern foaming kinetics and volume - their quantity and spatial positions critically modulate performance. The single-methylene difference dictates pH-dependent foam behavior and lipid tolerance, enabling targeted design of mild cleansers.
The self-assembly behavior of Gemini surfactants i.e. alkanediyl-alpha,alpha-bis(hydroxyethylmethylhexadecylammonium bromide) (16-s-16 MEA, 2Br(-); s = 4 and 6) was investigated in pure water and in water-organic mixtures (10 and 20 % v/v) of acetonitrile (ACN), dimethyl sulfoxide (DMSO), and dimethylformamide (DMF) by conducticty and surface tension method at 300-320 K. The critical micelle concentration (CMC), degree of micellar ionization (alpha), surface excess concentration (Gamma(max)), minimum molecular area at the interface (A(min)), surface pressure at the CMC (pi(CMC)), and thermodynamic parameters i.e. standard Gibbs free energies of micellization (Delta G degrees(m)), Gibbs free energy of adsorption (Delta G degrees(ads)), Gibbs free energy of transfer (Delta G degrees(trans)), standard Gibbs free energy of micellization per mole of surfactant monomer (Delta G degrees(tail)), enthalpy (Delta H degrees(m)), and entropy (Delta S degrees(m)), of micellization of the Gemini surfactant have also been determined. The CMC value increases with increasing spacer of Gemini surfactant (16-4-16, MEA 2Br(-)< 16-6-16, MEA 2Br(-)), volume percentage of solvents and temperatures. Acetonitrile shows the higher CMC values as compare to other solvents. The surface excess concentration value increases with inceasing volume perentage of solvents. The negative free energy of adsorption shows a greater propensity for adsorption at the air-solution interface than for micellization.
The present investigation employs a conductometric approach to investigate the influence of differing concentrations of the antibiotic drug sulfathiazole (STZ) and the additives glucose/urea on the micellization behavior of the anionic surfactant sodium dodecyl sulfate (SDS) in a slightly acidic environment (& rcy;& Ncy; 5.0) across a range of temperatures. In contrast to SDS in pure water, the CMC (critical micellar concentration) values of SDS decreased in the presence of STZ, facilitating micellization. Urea increases the CMC of the SDS + STZ system, whereas glucose decreases it. Unlike urea, which destabilizes water structure and diminishes hydrophobic contacts, glucose modifies the water structure, decreases the dielectric constant, and alters the electrostatic repulsions among the charged SDS head groups, making it harder for SDS molecules' hydrophobic tails to form micelles. Thermodynamic parameters (change in entropy of micellization, Delta S0m; enthalpy of micellization, Delta H0m; and Gibbs free energy of micellization, Delta G0m) and physicochemical variables (CMC and counter ion dissociation, alpha) have been used to characterise the interaction between SDS and STZ. The negative Delta G0m values reveal that the SDS + STZ mixture undergoes spontaneous micellization in both pure water and aqueous glucose/urea environments. The values of -Delta H0m and +Delta S0m for the SDS + STZ mixture indicate that both electrostatic and hydrophobic interactions play a crucial role in aggregation.
Cancer remains one of the significant causes of mortality throughout the globe, with treatment often requiring prolonged therapy. Multidrug resistance, primarily mediated by P-glycoprotein (P-gp) transporters, poses a considerable challenge in the long-term treatment of cancer. To overcome this, P-gp inhibitors can be co-administered for improved drug accumulation and therapeutic efficacy. In the present study, a total of 37 phytochemicals were evaluated for their potential P-gp blocking activity using molecular docking and Molecular Mechanics/Generalized Born Surface Area analysis against the P-gp protein (PDB ID: 6FN1) and compared with Verapamil as a reference P-gp inhibitor. Among the screened compounds, Andrographolide demonstrated the most favourable binding interactions and was further subjected to molecular dynamics simulations, confirming its stable interaction with P-gp. Subsequent in vitro cell line studies revealed that Andrographolide, at effective inhibitory concentrations, did not exhibit inherent cytotoxicity but significantly enhanced the cell internalization and cytotoxicity of paclitaxel, a known P-gp substrate. This suggests that Andrographolide plays a role in reversing multidrug resistance through P-gp inhibition, rather than direct cell killing, for effective cancer therapy. These findings indicate that co-administration of phytochemicals, such as Andrographolide, may enhance cell internalization and the efficacy of anticancer drugs, thereby improving chemotherapy outcomes.
Oxidative processes involving aminocarboxylate complexes and oxy-anions are intriguing for understanding cellular oxygen transport in biological systems. The proposed research aims to examine the implications of anionic, cationic, and neutral surfactants on the Ag + catalyzed peroxydisulphate (S 2 O 8 2− ) oxidation of [Co II CYDTA] 2− (CYDTA = trans-cyclohexane-1,2 diamine N,N,N′,N′-tetra acetic acid). The kinetics of oxidation in both aquatic and SLS/TX-100/CTAB micellar media are assessed by measuring an increase in absorbance at 538 nm. The impacts of pH, [Ag + ], [S 2 O 8 2− ], [Co II CYDTA 2− ], ionic strength, [Surfactant], and temperature were investigated. The inclusion of supplementary cations and the reaction medium’s ionic strength does not influence the reaction rate, indicating that the reaction occurs through the formation of ion pairs. Anions increased catalysis, suggesting an outer sphere mechanism. The analysis of various concentrations revealed that the reaction under investigation exhibited a first-order dependence on [Co II CYDTA 2− ], [Ag + ], and [S 2 O 8 2− ]. The presence of CTAB micelles facilitated approximately 3.3-fold enhancement in the oxidation rate. TX-100 moderately facilitates the oxidation of [Co II CYDTA] 2− , whereas SLS, an anionic surfactant, diminishes the oxidation rate. As a catalyst, CTAB exhibits the best compatibility with Ag + metal salt. The proposed mechanistic approach is further supported by the computed activation parameters.
Fungal skin infections often require prolonged therapy; however, conventional ciclopirox olamine (CO) formulations exhibit poor penetration and limited skin retention, reducing efficacy. This study aimed to develop a CO-loaded cubosomal hydrogel patch to enhance skin permeation, retention, and antifungal activity. Cubosomes were prepared using glyceryl monooleate and Kolliphor 407 by the top-down technique and optimized through a 23 factorial design for particle size and entrapment efficiency. The optimized cubosomal dispersion was incorporated into a hydrogel patch containing sodium alginate and hydroxypropyl methylcellulose by solvent casting. Formulations were evaluated for physicochemical properties, drug release, permeation, antifungal activity, histocompatibility, and stability. Optimized cubosomes showed nanosized particles with high entrapment efficiency and stable morphology. FTIR and XRD confirmed successful encapsulation without interaction, while SEM revealed a porous surface enabling controlled diffusion. The optimized patch exhibited sustained release (97.82 % over 48 h), enhanced skin permeation (96.41 %), and stronger antifungal activity against Candida albicans compared to marketed cream. It demonstrated suitable mechanical strength, pH compatibility, biocompatibility, and three-month stability.
In this work, sulfonate Gemini surfactant with two trisiloxane hydrophobic chains (2Si3SO3Na) and sulfonate surfactant with single trisiloxane hydrophobic chain (Si3SO3Na) were prepared. The structure of the surfactant was characterised by Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance and thermogravimetric analysis. Surface tension was used to study the thermodynamic parameters, such as the critical micelle concentration (CMC) and the corresponding surface tension at the CMC (gamma CMC ), of two trisiloxane surfactants. Additionally, surface tension measurements were employed to investigate the effects of temperature and inorganic salts on surface activity. The results showed that at 298 K, the CMC and gamma CMC of 2Si3SO3Na were 0.24 mu mol L-1 and 23.78 mN m-1, respectively, significantly lower than those of Si3SO3Na. Dynamic Light Scattering tests indicated that the aggregate size of 2Si3SO3Na at CMC concentration was much larger than that of Si3SO3Na at its CMC concentration. Finally, wettability tests demonstrated that 2Si3SO3Na exhibited higher interfacial activity and wettability compared to Si3SO3Na.
Cyperus rotundus L. essential oil (CEO) was loaded into covalent organic polymer materials (PdIs) and characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller theory (BET), and Thermogravimetric Analysis (TG). The main components of CEO were identified as cyperenone (13.43 %), cyperene (10.01 %), alpha-cyperone (5.83 %), caryophyllene oxide (3.15 %), Zierone (2.97 %), and Cyperene epoxide (2.07 %). The stability of PdIs/CEO was systematically investigated. The antioxidant activities of CEO and PdIs/CEO were evaluated based on their ability to scavenge DPPH and ABTS free radicals. A CCK-8 assay was employed to determine the concentrations of sample, and a lipopolysaccharide (LPS)-induced RAW264.7 cell model was established to assess their anti-inflammatory effects. Both CEO and PdIs/CEO exhibited strong antioxidant activity. They significantly inhibited the production of nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha). At a concentration of 150 mu g/mL, the maximum inhibition rates for TNF-alpha, and IL-6 reached 91.63 % and 96.23 %, respectively. This study demonstrates that PdIs/CEO has promising potential for applications in food, pharmaceutical, and related fields.
A new approach has been developed to improve the dispersion of reinforcements in order to optimize the properties of nanocomposite materials based on poly (vinyl alcohol) (PVA) matrices. The approach consists of combining epoxy-functionalized graphene with organophilic clay (Mt@HTAB). X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM) reveal adequate dispersion of graphene sheets and clay layers throughout the PVA matrix. Various mixtures based on PVA (polyvinyl alcohol), montmorillonite modified with hexadecyltrimethylammonium bromide (Mt@HTAB) and graphene were prepared using a solvent mixing process.The flammability properties of these materials were evaluated based on thermogravimetric analysis (TGA) and cone calorimeter tests.The combination of graphene and Mt@HTAB increased thermal stability and reduced flammability (heat release rate (HRR), total heat release rate (THR), and ignition time (TTI)). The ternary mixture has a maximum heat release rate (PHRR) that is 53 % lower than that of pure PVA. The structure of the residues from the cone calorimeter tests was examined using scanning electron microscopy (SEM). This process revealed the presence of compact, dense carbon formed as a result of the combustion of binary and ternary nanocomposites.The ternary mixture has a maximum heat release rate (PHRR) that is 53 % lower than that of pure PVA. The structure of the residues from the cone calorimeter tests was examined using scanning electron microscopy (SEM). This process revealed the presence of compact, dense carbon formed as a result of the combustion of binary and ternary nanocomposites.
The micellization behavior of mixed micellar systems containing cetyldiethylethanolammonium bromide (CDEEAB) and cetyltriphenylphosphonium bromide (CTPB) surfactants with 10 % (v/v) and 20 % (v/v) solvents i.e. dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) were investigated using conductivity and surface tension measurements at 300 K. Critical micelle concentration (CMC) values increases with increasing mole fraction of CDEEAB. The interfacial properties, Γ max (maximum surface excess), Α min (minimum surface area per molecule) and π CMC (surface pressure at the CMC) have been determined. The Clint equation, Rosen and Rubingh models have been used to calculate interaction parameters ( β m and β σ ). The findings show that protonic solvents change the physicochemical characteristics of the cationic surfactants and significantly improve synergistic interactions. Interestingly, the addition of DMSO (10–20 % v/v) causes a significant increase in the CMC of the CDEEAB + CTPB mixed system. This effect is more noticeable than that of DMF, demonstrating the solvent-dependent modulation of mixed micelle formation. Thermodynamic parameters, Δ G a d s o ${\Delta \mathrm{G}}_{ads}^{o}$ , Δ G e x o ${\Delta \mathrm{G}}_{ex}^{o}$ , Δ G m o ${\Delta \mathrm{G}}_{m\hspace{0.17em}}^{o\hspace{0.17em}}$ values are negative indicating the stability and spontaneity of the mixed micelle.
In gas well operations, efficient foam drainage and prevention of hydrate aggregation are crucial for maintaining production efficiency and preventing blockages. This study presents a novel dual-functional surfactant system (TPS) composed of cetyltrimethylammonium chloride (CTAC), alkylphenol ethoxylate (OP-10), and sodium dodecyl sulfate (SDS), designed to enhance both foam drainage and hydrate anti-aggregation. The optimized TPS formulation (0.05 % CTAC + 0.5 % OP-10 + 0.02 % SDS) demonstrated exceptional foaming ability with an initial foam volume of 540 ml and a half-life of 7.5 min at 50 °C. The system maintained high liquid-carrying capacity (72.5 %) even at elevated temperatures (65 °C) and in the presence of methanol, which is commonly used as a hydrate inhibitor. Differential scanning calorimetry (DSC) and microscopic observations revealed that TPS significantly reduced the phase transition temperature of tetrahydrofuran (THF) hydrates, thereby suppressing hydrate formation and aggregation. The compatibility of TPS with polyvinylpyrrolidone (PVP), a common kinetic hydrate inhibitor and foam stabilizer, enhanced foam stability. This dual-functional system offers a robust solution for improving gas well productivity and mitigating hydrate-related risks, with potential applications in complex oil and gas field environments.
