Sodium Decyl Research Articles

Interaction of piroxicam with micelles: Effect of hydrophobic chain length on structural switchover

Molecules, whose p K a values can be easily fine-tuned by their microenvironment, are expected to be profoundly affected by the heterogeneous environments of membranes. Membrane parameters can have a strong effect in choosing a particular structural form of a molecule for incorporation/interaction. A case study has been presented for piroxicam, a non-steroidal anti-inflammatory drug of oxicam group, whose targets are cyclooxygenases, which are membrane active proteins. The structural dynamism of piroxicam is reflected in the ease with which it can switchover or convert from one prototropic form to the other guided by its environment. In this work we have studied the effect of varying hydrophobic chain length and surface charges in fine-tuning the interaction of piroxicam with micelles. Interaction of piroxicam with three types of micelles with identical negatively charged head groups and varying tail lengths viz., sodium dodecyl sulfate (S12S), sodium decyl sulfate (S10S) and sodium octyl sulfate (S8S) shows that there is a shift in the apparent p K a in the direction that favors the switchover or conversion from the anionic form to the global neutral form. The binding constants of piroxicam with three micelles show a linear dependence on chain length. Interaction was also studied with micelles having oppositely charged head groups and different chain lengths viz., dodecyl N, N, N-trimethyl ammonium bromide (DTAB) and cetyl N, N, N-trimethyl ammonium bromide (CTAB). For micelles having identical chain lengths but oppositely charged head groups viz., S12S and DTAB, p K a shifts in two opposite directions compared to that in the absence of any surfactant. This is expected when electrostatic force is the only driving force. This case study demonstrates the effect of hydrophobic chain length and surface charges in fine-tuning the equilibrium between different structural forms of piroxicam. Our results also imply that for structurally dynamic drugs like piroxicam the nature of the biomembranes, characterized by different membrane parameters, should play a crucial role in choosing a particular structural form of the drug that will be finally presented to their targets.

Size Control of Styrene Oxide−Ethylene Oxide Diblock Copolymer Aggregates with Classical Surfactants: DLS, TEM, and ITC Study

The interactions between the diblock copolymer S(15)E(63) and the surfactants sodium dodecyl sulfate (SDS), sodium decyl sulfate (SDeS), and sodium octyl sulfate (SOS) have been investigated by dynamic light scattering (DLS), transmission electron microscopy (TEM), and isothermal titration calorimetry (ITC). The surfactants with the same headgroup differentiate in their chain length. At 20 degrees C, the block copolymer is associated into micelles with a hydrodynamic radius of 11.6 nm, which is composed of a hydrophobic styrene oxide (S) core and a water-swollen oxypolyethylene (PEO or E) corona. The different copolymer/surfactant systems have been studied at a constant copolymer concentration of 2.5 g dm(-3) and in a vast range of surfactant concentrations, from 7.5 x 10(-6) up to 0.75 M. When SDS and SDeS are added to the block copolymer solution, different regions are observed in the DLS data: at low surfactant concentrations (c < 1.0 x 10(-4) M), single surfactant molecules associate with the copolymer micelle, probably the former being solubilized in the micelle core, leading to a certain disruption of the mixed micelle due to repulsive electrostatic interactions between surfactant headgroups followed by a stabilization of the mixed micelle. At higher concentrations (1.0 x 10(-4) < c < 0.1 M), two types of copolymer-surfactant complexes coexist: one large copolymer-rich/surfactant complex and one small complex consisting of one or a few copolymer chains and rich in surfactants. At higher SDS and SDeS concentrations, complete disintegration of mixed micelles takes place. In contrast, SOS-S(15)E(63) interactions are less important up to surfactant concentrations of 0.05 M due to its higher hydrophilicity, reducing the hydrophobic interactions between surfactant alkyl chains and copolymer micelles. At concentration larger than the critical aggregation concentration (cac) of the system, 0.05 M, disruption of copolymer micelles occurs. These regions have been confirmed by transmission electron microscopy. On the other hand, the titration calorimetric data for SDS and SDeS present an endothermic increase indicating the formation of mixed copolymer-rich-surfactant micelles. From that point, important differences in the ITC plot for both surfactants are present. However, the ITC curve obtained after titration of a SOS solution in the copolymer solution is quite similar to that of its titration in water.

On the Role of Triethyl Borate in the Reduction of Elemental Selenium, Diselenide Dianions, Sodium Decyl Diselenolate, and Didecyl Diselenide with Sodium Borohydride

Addition of triethyl borate to disodium diselenide or to sodium decyl diselenolate allows their reduction with sodium borohydride which otherwise does not take place.

Kinetics of degradation and oil solubility of ester prodrugs of a model dipeptide (Gly-Phe).

Oil-based depot formulations may constitute a future delivery method for small peptides. Thus, a requirement is attainment of sufficient oil solubility for such active compounds. A model dipeptide (Gly-Phe) has been converted into lipophilic prodrugs by esterification at the C-terminal carboxylic acid group. The decomposition kinetics of octyl ester of Gly-Phe (IV) has been investigated at pH 7.4 (37 degrees C) and IV was shown to degrade by first-order kinetics via two parallel pathways (1) intramolecular aminolysis resulting in formation of a 2,5-diketopiperazine and (2) hydrolysis of the ester bond producing the dipeptide. The cyclisation reaction was dominating in the decomposition of methyl (II) butyl (III) octyl (IV) decyl (V) and dodecyl (VI) esters of Gly-Phe at pH 7.4. However, this degradation pathway was almost negligible for pH below 6. During degradation of the dipeptide esters in 80% human plasma pH 7.4 (37 degrees C) a minimal amount of cyclo(-Gly-Phe) was formed. A faster degradation of the esters in 80% human plasma pH 7.4 compared to those in aqueous solution pH 7.4 was suggested to be due to fast cleavage of the peptide bond. Low oil solubilities for Gly-Phe and the hydrochlorides of the dipeptide esters III and VI were observed. Although the solubility of Gly-Phe in oil solutions was enhanced by hydrophobic ion pairing with sodium decyl sulfonate the oil solubility was still less than 1 mg Gly-Phe/ml. By addition of a solubiliser, 10% N,N-dimethylacetamide (DMA), to Viscoleo the solubility of the HIP complexes increased significantly. The present study indicates that sufficient oil solubility might only be obtained for relatively small peptides by using the prodrug approach in combination with solubility enhancing organic solvents like DMA.

Structural Investigation on the Poly(vinylpyrrolidone)−Water System in the Presence of Sodium Decyl Sulfate and Sodium Decanesulfonate: A Small Angle Neutron Scattering Study

Small angle neutron scattering (SANS) has been used to study the interaction of sodium decyl sulfate (C10OS) and sodium decanesulfonate (C10S) with poly(vinylpyrrolidone) (PVP). The measurements were performed on aqueous solutions of C10OS and C10S in the presence and absence of PVP. In all ternary systems the polymer concentration was kept constant at 1 wt %, and the surfactant molal concentration ranged from 0.002 to 0.150 mol kg-1. The analysis of the collected SANS profiles confirms the absence of any appreciable interaction between PVP and C10S in contrast with what observed for the PVP−C10OS−D2O system. In this latter system, in fact, a clear interaction peak in the scattering pattern appears well below the cmc of the surfactant, which suggests a complex formation between PVP and C10OS. The preferential interaction of poly(vinylpyrrolidone) toward sodium decyl sulfate with respect to sodium decanesulfonate reflects the difference in the chemical structure of the two surfactants that produces meaning...

Effects of Various Surfactants on Rheological Properties of Maize Starch Granules

ABSTRACTIn this study, the formation of complexes between surfactants and the helical chains of amylopectins was confirmed. Nonionic surfactants with hydrophobic and hydrophilic groups of appropriate size and chemical structure enhanced the swelling and gelatinization processes of starch granules. Hydrophobic groups form complexes with the amylose and linear chains of amylopectin by becoming inserted into the hydrophobic inner area of the helical structures. The hydrophilic groups help the approach of the hydrophobic groups into the hydrated molecular chains and thus aid the formation of the complex. Among the anionic surfactants tested, SDS and sodium n‐decyl benzenesulfate caused maximum swelling and gelatinization peaks. The average length of the amylopectin exterior chains is almost the same as that of the hydrophobic chains of SDS (16.9 Å) and of sodium decyl benzenesulfate (18.2 Å). This suggests that these anionic surfactants form rigid complexes with the exterior of the amylopectin by fitting their hydrophobic chains to the hydrophobic inside of the helical structures of these short exterior chains. This process was clarified by NMR analysis and by a decrease in the complex with the addition of iodine. The hydrophobic alkyl chains of anionic and cationic surfactants fix to the edge of the starch molecular chains by forming inclusion complexes with the helical chains of the amylopectin. Cationic ions interact with the starch molecular chains, causing a negative charge that results in a more rapid and efficient swelling of the starch granules. A decrease in setback value occurs due to the inhibition of rearrangement among the starch molecular chains. With SDS, the complex molecular chains become more extensively developed through the repulsion effects of the anionic ions resulting in a larger swelling power and gelatinization peak.

Complex Formation between Poly(vinylpyrrolidone) and Sodium Decyl Sulfate Studied through NMR

Recent experimental studies have shown a preferential interaction of poly(vinylpyrrolidone) (PVP) toward the alkyl sulfate surfactants rather than toward those belonging to the alkyl sulfonate series. To gain information on the complex formation between PVP and the alkyl sulfate surfactants, we have performed 1H and 13C NMR and NOESY measurements on aqueous solutions of sodium decyl sulfate (C10OS) in the presence and absence of PVP at 1wt %. The results show that C10OS interacts with PVP, forming micelle-like clusters bound onto the polymer, and furthermore suggest that the PVP−C10OS complex formation implies the synergic effects of the electrostatic attractions between the surfactant headgroup and the nitrogen and oxygen atoms in the pyrrolidone ring of PVP and of the hydrophobic interaction between the surfactant alkyl moiety and the ring carbons of PVP.

Effect of equimolar salt to decyltrimethylammonium decyl sulfate on vesicle formation and surface adsorption

The aqueous solution of mixture of sodium decyl sulfate (SDeS) and decyltrimethylammonium bromide (DeTAB) has been found to form equilibrium multilamellar vesicles (MLV) spontaneously. We measured the surface tension of the aqueous solution of 1:1 mixture of SDeS and DeTAB as a function of temperature T at various molalities m ̂ under atmospheric pressure. The surface density, the entropy of adsorption and the entropy of vesicle formation are evaluated and compared with those of the decyltrimethylammonium decyl sulfate (DeTADeS) aqueous solution system to investigate the role of small counterions in the mechanism of equilibrium vesicle formation. The saturated surface density Γ ̂ H,C vs T curve of the SDeS/DeTAB system sits below that of the DeTADeS system. Therefore, sodium and bromide ions are negatively adsorbed and nevertheless, they neutralize the electric charge of the decyl sulfate ion DeS − and the decyltrimethylammonium ion DeTA + to some extent to weaken the electrostatic attraction between the polar head groups in the adsorbed film. The net surfactant concentration required for vesicle formation was larger in the SDeS/DeTAB system. Hence, the electrostatic attraction between the polar head groups of the surfactant ions which is one of the major driving forces for vesicle formation is weakened by the presence of the counterions Na + and Br −. Small but distinct changes in the surface density and the entropies of MLV formation of the SDeS/DeTAB system from those of the DeTADeS system were also found.

Micellization of Sodium Decyl Naphthalene Sulfonate Studied by1H NMR

H-1 chemical shift changes of a newly synthesized anionic surfactant, sodium decyl naphthalene sulfonate (SDNS), show that its critical micellar concentration (cmc) lies between 0.82 and 0.92 mM, which is in agreement with that measured by the surface tension method (0.8 mM). The difference in aromatic ring current effect on the naphthyl protons, the different changes in their spin-spin relaxation times upon micellization, and the appearance of cross-peaks between intermolecular protons in the aqueous micellar solution give information about the relative arrangement of the naphthyl rings in the SDNS micelles.

Micelle-sequestered dissociation of cationic DNA-intercalated drugs: unexpected surfactant-induced rate enhancement.

Detergent sequestration using micelles as a hydrophobic sink for dissociated drug molecules is an established technique for determination of dissociation rates. The anionic surfactant molecules are generally assumed not to interact with the anionic DNA and thereby not to affect the rate of dissociation. By contrast, we here demonstrate that the surfactant molecules sodium dodecyl sulfate (SDS), sodium decyl sulfate, and sodium octyl sulfate all induce substantial rate enhancements of the dissociation of intercalators from DNA. Four different cationic DNA intercalators are studied with respect to surfactant-induced dissociation. Except for the smallest intercalator, ethidium, the dissociation rate constants increase monotonically with surfactant concentration both below cmc and (more strongly) above cmc, much more than expected from electrostatic effects of increased counterion concentration. The rate enhancement, most pronounced for the bulky, multicationic, hydrophobic DNA ligands in this study, indicates a reduction of the activation energy for the ligand to pass out from a deeply penetrating intercalation site of DNA. The discovery that surfactants enhance the rate of dissociation of cationic DNA-intercalators implies that rate constants previously determined by micelle-sequestered dissociation may have been overestimated. As an alternative, more reliable method, we suggest instead the addition of excess of dummy DNA as an absorbent for dissociated ligand.

On the formation of surface micelles at the metal ∣ electrolyte interface

The long-term capacity–time dependence of sodium decyl- and sodium dodecyl sulfate were measured at the mercury ∣ electrolyte interface for 0.1 M Na 2SO 4 electrolyte in the temperature range from 20 to 50 °C at the potential of maximal adsorption. All capacity–time dependences exhibited a slow increase of the capacity after a sudden decrease in the short-term range. The corresponding long-term time dependence of the degree of coverage can be well described theoretically with a first-order surface reaction in which surface micelles are formed from a condensed film of perpendicularly interdigitated adsorbed molecules. The temperature dependence of the ratio of final equilibrium capacity to initial minimal capacity can be explained by the formation of hemispherical surface micelles in the case of sodium decyl sulfate and sodium dodecyl sulfate for the whole temperature range. A generalized packing parameter was introduced which involves the increase or decrease of the mutual distance of the head groups as well as the tail groups (and consequently their effective surface area) due to electrolyte ions or other surfactants. A necessary extension of the present electrochemical adsorption theory is discussed.

Formation of the molten globule-like state of cytochrome c induced by n-alkyl sulfates at low concentrations.

The molten globule state of cytochrome c is the major intermediate of protein folding. Elucidation of the thermodynamic mechanism of conformational stability of the molten globule state would enhance our understanding of protein folding. The formation of the molten globule state of cytochrome c was induced by n-alkyl sulfates including sodium octyl sulfate, SOS; sodium decyl sulfate, SDeS; sodium dodecyl sulfate, SDS; and sodium tetradecyl sulfate, STS, at low concentrations. The refolding states of the protein were monitored by spectroscopic techniques including circular dichroism (CD), visible absorbance and fluorescence. The effect of n-alkyl sulfates on the structure of acid-unfolded horse cytochrome c at pH 2 was utilized to investigate the contribution of hydrophobic interactions to the stability of the molten globule state. The addition of n-alkyl sulfates to the unfolded state of cytochrome c appears to support the stabilized form of the molten globule. The m-values of the refolded state of cytochrome c by SOS, SDeS, SDS, and STS showed substantial variation. The enhancement of m-values as the stability criterion of the molten globule state corresponded with increasing chain length of the cited n-alkyl sulfates. The compaction of the molten globule state induced by SDS, as a prototype for other n-alkyl sulfates, relative to the unfolded state of cytochrome c was confirmed by Stokes radius and thermal transition point (T(m)) measured by microviscometry and differential scanning calorimetry (DSC), respectively. Thus, hydrophobic interactions play an important role in stabilizing the molten globule state.

Interactions between Mucin and Alkyl Sodium Sulfates in Solution. A Light Scattering Study

The properties of negatively charged mucin in aqueous solutions and its interaction with anionic sodium alkyl sulfates with different hydrocarbon chain lengths were studied by means of dynamic light scattering. It was observed that mucin forms aggregates in aqueous solutions with a hydrodynamic radius above 500 nm. These aggregates dissolve when sodium dodecyl sulfate or sodium decyl sulfate is present at sufficiently high concentration, above about 0.2 cmc (critical micellar concentration). On the other hand, sodium octyl sulfate is not very effective in dissolving the mucin aggregates. The hydrodynamic radius of the dissolved mucin, decorated with some associated surfactant, is found to be in the range of 40−90 nm. The observation that the dissolving power of the sodium alkyl sulfates decreases with decreasing surfactant chain length suggests that the association between the surfactant and mucin is hydrophobically driven. The kinetics of the dissolution process depends on the surfactant concentration, a higher surfactant concentration giving rise to a more rapid dissolution of the aggregates. It was also observed that when the ionic strength is increased, the surfactant concentration needed to dissolve the mucin aggregates decreases. This can be explained by reduction of repulsive electrostatic forces by the salt.

Structural characterization of bacteriophage M13 solubilization by amphiphiles

The structural properties of bacteriophage M13 during disassembly were studied in different membrane model systems, composed of a homologue series of the detergents sodium octyl sulfate, sodium decyl sulfate, and sodium dodecyl sulfate. The structural changes during phage disruption were monitored by spin-labeled electron spin resonance (ESR) and circular dichroism spectroscopy. For the purpose of ESR spectroscopy the major coat protein mutants V31C and G38C were site-directed spin labeled in the intact phage particle. These mutants were selected because the mutated sites are located in the hydrophobic part of the protein, and provide good reporting locations for phage integrity. All amphiphiles studied were capable of phage disruption. However, no significant phage disruption was detected below the critical micelle concentration of the amphiphile used. Based on this finding and the linear dependence of phage disruption by amphiphiles on the phage concentration, it is suggested that the solubilization of the proteins of the phage coat by amphiphiles starts with an attachment to and penetration of amphiphile molecules into the phage particle. The amphiphile concentration in the phage increases in proportion to the amphiphile concentration in the aqueous phase. Incorporation of the amphiphile in the phage particle is accompanied with a change in local mobility of the spin-labeled part of the coat protein and its secondary structure. With increasing the amphiphile concentration in the phage particle, a concentration is reached where the concentration of the amphiphile in the aqueous phase is around its critical micelle concentration. A further increase in amphiphile concentration results in massive phage disruption. Phage disruption by amphiphiles appears to be dependent on the phage coat mutations. It is concluded that phage disruption is dependent on a hydrophobic effect, since phage solubilization could significantly be increased by keeping the hydrophilic part of the amphiphile constant, while increasing its hydrophobic part.

Nucleophilic substitution sulfonation in emulsions: effect of the surfactant counterion and different decyl halide reactants

The nucleophilic substitution reaction between sodium sulfite and different decyl halides was carried out in emulsions formed by the two-tailed cationic surfactants dioctyldimethylammonium chloride R 2(Me) 2N +Cl − or bromide R 2(Me) 2N +Br −. The oil phase of the emulsion consisted of the decyl halide reactant. The effects of R 2(Me) 2N +Br − concentration and different decyl halide reactants on the conversion were studied. A decyl chloride intermediate formed when decyl iodide or decyl bromide were reacted in R 2(Me) 2N +Cl − emulsions. The intermediate reacted further to the final product, sodium decyl sulfonate, at a rate which depended on the decyl halide reactant. The conversion to C 10H 21SO 3Na versus R 2(Me) 2N +Br − concentration displayed a broad maximum. The reactivity of the decyl halides increased in the order: decyl chloride, bromide and iodide. Increasing decyl iodide concentration at a constant R 2(Me) 2N +Cl − concentration and a constant initial mole ratio of Na 2SO 3 to C 10H 21I increased the reaction rate, while the conversion decreased. Plateaus in the conversions to C 10H 21SO 3Na and C 10H 21Cl were reached for the run at 800 mM equimolar surfactant and reactant concentrations. The pseudophase ion exchange model, with the assumption of trapped amounts of the decyl halides within the emulsion oil core and thus not available for the reaction, described the experimental results.

On the Presumed Specific Interaction of Anionic Surfactants with Nonionic Polymers. Aqueous Solution of Sodium Alkylsulfonate in the Presence of Poly(vinylpyrrolidone): An “Excluded Volume” Effect

Surface tension, viscosity, intradiffusion, and interdiffusion measurements have been performed on aqueous solutions of sodium octyl sulfonate, sodium decyl sulfonate, and sodium undecyl sulfonate, in the presence of poly(vinylpyrrolidone) at 1% w/w. The experimental measurements for each ternary system were performed in a range of surfactant concentration including the binary critical micelle concentration of the surfactant. The overall picture of the properties studied suggests the absence of a specific interaction between poly(vinylpyrrolidone) and alkylsulfonate surfactants. The experimental diffusion coefficients can be interpreted in terms of an “excluded volume” effect produced by the presence of the polymer in solution.

Effects of Sulfobetaine−Sodium Decyl Phosphate Mixed Micelles on Deacylation and Indicator Equilibrium

Critical micelle concentrations were measured for mixed micelles of sodium decyl phosphate (NaDeP) and sulfobetaines (CnH2n+1N+Me2(CH2)3SO3-, SB3-n, n = 10, 12, 14, 16), and values of pHapp were calculated from spectroscopic data on the extent of deprotonation of 1-dodecylpyridinium-3-aldoxime bromide. For 0.1 M total surfactant, rate constants of hydrolyses of 2,4-dinitrophenyl acetate and octanoate (DNPA and DNPO, respectively) and benzoic anhydride (Bz2O) were fitted quantitatively in terms of reactions of OH- and decyl phosphate ion on the assumption that sulfobetaine micelles increased the reactivity of decyl phosphate ion.

Nucleophilic Substitution Sulfonation in Microemulsions and Emulsions

Microemulsions and emulsions can be used to carry out reactions in which the reactants are not soluble in the same phase. In this work, the nucleophilic substitution reaction between an organic soluble compound, decyl bromide, and a water-soluble salt, Na2SO3, to produce sodium decyl sulfonate was carried out in batches in o/w microemulsions and emulsions formed with the two-tailed cationic surfactant dioctyldimethylammonium chloride, R2(Me)2N+Cl-. The surfactant counterion Cl-, substituted for bromide to give decyl chloride, an intermediate that further reacted to give the final product. The effects of stirring and preconditioning, surfactant concentration, the concentration of decyl bromide, and the initial mole ratio of the reactants on the conversion to sodium decyl sulfonate and decyl chloride were determined. Although phase separation occurred and emulsions formed in most of the samples, stirring and preconditioning did not have a significant effect on the conversion. An optimum surfactant concentration was found at which the maximum conversion to the final product was obtained. Increasing the concentration of decyl bromide increased the molar rate of sodium decyl sulfonate formation, but the conversion dropped. Increasing the mole ratio of Na2SO3 to decyl bromide increased conversion to the final product and reduced conversion to the intermediate. A pseudophase ion-exchange model with the interfacial volume as a fitted parameter, varying only with the surfactant concentration, represented well the experimental results.

Poly(ethylene oxide)13-Poly(propylene oxide)30-Poly(ethylene oxide)13 Electrolyte Interactions in Aqueous Solutions at Some Temperatures

The apparent molar volumes (VΦ,C) of poly(ethylene oxide)13-poly(propylene oxide)30-poly(ethylene oxide)13 (Pluronic L64) in aqueous electrolyte solutions were determined as functions of L64 concentrations at some temperatures. The electrolytes studied are sodium perchlorate, sodium decyl sulfate (NaDeS), sodium decanoate (NaDec), and decyltrimethylammonium bromide (DeTAB). Sodium perchlorate plays the same role as temperature on VΦ,C data because of its destructuring solvent effect. At a given temperature, sodium decyl sulfate, in both the dispersed and micellized states, strongly affects not only the VΦ,C vs mC profile but also their values. In fact, VΦ,C decreases with mC to the critical micelle concentration (cmc), beyond which it increases, tending to level off. The experimental data are consistent with the idea that the addition of dispersed L64 to the micellar NaDeS solutions leads to the formation of NaDeS micelles with aggregation numbers lower than those in pure water; this likely results from t...

Average Orientation and Location of Benzyl Alcohol-d5 and Alkyl Benzyl-d5 Ethers in Anionic Nematic Lyotropic Liquid Crystals

Deuterium quadrupole splittings of benzyl alcohol-d5 and a series of alkyl benzyl-d5 ethers, with linear aliphatic chains from 1 to 12 carbon atoms, were measured using 2H NMR spectroscopy. These molecules were dissolved in ND anionic nematic lyotropic liquid crystals prepared with sodium decyl sulfate (NaDS) and cesium decyl sulfate (CsDS). Using the quadrupole splittings, the two order parameters that completely describe the average orientation of the aromatic ring were calculated. From these values, we have inferred the mechanism of incorporation of the guest molecules into the superstructure of the aggregate. The effect of the added molecules on the integrity of the aggregate seems to depend on the electrostatic characteristics of the surface as well as the hydrophobic properties of the guest molecule. The quadrupole splittings suggest that benzyl alcohol is positioned near the interface, possibly hydrogen bonding with the interfacial water. This disrupts the integrity of the interface, particularly i...