Mixed Micellar System Research Articles

Enhanced Ocular Drug Delivery of Dexamethasone Using a Chitosan-Coated Soluplus®-Based Mixed Micellar System

Background: This study introduces a novel dexamethasone (DEX) mixed micellar system (DEX-MM) using Soluplus® and Pluronic F-127 (PF127) to enhance ocular drug delivery. The enhancement of ocular application properties was achieved by creating a chitosan-coated DEX-MM (DEX-CMM), which promotes better adherence to the ocular surface, thereby improving drug absorption. Methods: Using the solvent evaporation method, a formulation was developed with a Soluplus®-to-drug ratio of 1:10, enhanced with 0.25% PF127. After dispersing in water, 1% chitosan (CS) was added. The stability and integrity of DEX within the micelles were verified using attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR) and differential scanning calorimetry (DSC). Additionally, in vitro and ex vivo drug release studies were conducted. Results: DEX-CMM (F6) demonstrated a particle size of 151.9 ± 1 nm and a polydispersity index (PDI) of 0.168 ± 0.003, suggesting uniformity and high electrostatic stability with a zeta potential of +35.96 ± 2.13 mV. The non-Fickian drug release mechanism indicated prolonged drug retention. Comparative analyses showed DEX-CMM outperforming a standard DEX suspension in drug release and ocular tissue permeation, with flux measurements significantly higher than the DEX suspension. Conclusion: The study confirmed the efficacy of DEX-CMM in enhancing drug delivery to ocular tissues, evidenced by improved permeability. Safety evaluations using the HET-CAM test demonstrated that DEX-CMM was non-irritant, supporting its potential for effective ocular drug delivery.

Investigation the binding and partition properties of azithromycin drug using drug-surfactant mixed micelles in the presence of trisodium citrate electrolyte

The significance of mixed micelle in pharmaceutical industries is improving the binding and solubility of poorly water-soluble drugs. This work highlighted the effect of organic counterion (NAC) for improving the micellization association of zwitterionic (CAPB) and cationic drug (DPC) by surface tension measurements. The Corrin–Harkins (CH) approach assessed the CAPB, DPC and CAPB-DPC counterion binding values for DPC in the aqueous and NAC media at 25 °C. The counterion binding B for CAPB-DPC from αDPC 1.0–0.0 was found 0.536, 0.3801, 0.368, 0.355, 0.310 and 0.272 in the presence of NAC which indicated that DPC improved the counterion binding in the mixed micellar system. The Gibb’s free energy of micellization (ΔGmic°) were increased and became more negative, suggesting that the CAPB–DPC interaction was controlled by electrostatic interaction. Furthermore, the application of mixed micelle was utilized to enhance the binding constant (LogKb) and partition coefficient (LogKx) of the poorly water-soluble drug (AZI) in aqueous and NAC media at 25 °C using a UV spectrophotometer. From UV spectra, The LogKb and LogKx of AZI were lower in single micellar systems and higher in mixed micellar systems of CAPB-DPC. The maximum LogKb values at αDPC 0.4 were found 3.091, 3.233, 3.417, and 3.368 and LogKx values were found 4.749, 4.919, 5.087 and 5.049 in the presence of 0.0, 0.5, 3.0 and 20 mmol L−1 of NAC. AZI molecules are found in the palisade layer of mixed micelle when the DPC mole fraction is less than αDPC 0.6, while more than αDPC 0.6 causes steric hindrance, increasing hydrophobicity in the system. Furthermore, surfactant-drug mixed micelles could serve as poorly drug-solubilizing agents, as well as a multidrug delivery system in pharmaceutical applications.

Unveiling the role of solubilization of metformin hydrochloride assimilated in nonionic surfactants mediated mixed micellar assemblies

This study examines the distribution of an antidiabetic drug metformin hydrochloride (MNH) between water and mixed micellar environments produced by nonionic surfactants Tween 80 (TW-80) and Triton X-100 (TX-100). In our research, we described the UV–visible absorption spectra of a drug at various surfactant concentrations above and below critical micelle concentration (CMC). When employing TX-100, the absorbance spectra appeared to shift towards shorter wavelengths (blue shift) and there was an increase in absorbance intensity (hyperchromic shift), while using Tween 80, absorbance intensity increased (hyperchromic shift). We estimated the partition coefficient (Kx) from differential absorption data and utilized it to derive the free energy of partition (∆Gp). The partition coefficient in a single micellar system was found to be 7.82×106 and 1.79×106 in the presence of TW-80 and TX-100, respectively. The partition coefficient for the MNH/TW-80 system in a mixed micellar system reaches its maximum value of 1.08×107 when TX-100 is present at 1.26×106 M, indicating a considerable increase in the solubilizing power of micelles. The results showed that mixed micelles of TX-100/TW-80 were more effective for the solubilization of MNH than their individual micelles. It was crystal clear from the negative values of ∆Gb that binding is also spontaneous.

The role of chelating agent in the self-assembly of amphoteric surfactants

Hypothesis: Limited research has been conducted on the influence of chelating agents on the self-assembly process in surfactant solutions. The traditional approach assumes the chelating agent only interferes as a salting-out ion, therefore promoting surfactant separation. However, the opposite behavior has been observed for iminodipropionate based surfactants, in which the presence of chelating agents of the aminopolycarboxylate type increases solubility of nonionic ethoxylated surfactants in mixed micellar systems. Specific interaction between chelating agents-surfactants can be an important parameter in the self-assembly processes.Experiments: Physicochemical properties of solutions containing amphoteric surfactant and tetrasodium glutamatediacetate have been investigated. Macroscopic properties, such as viscosity and cloud point, were evaluated in the presence of a non-water-soluble alkyl ethoxylated surfactant. Interactions between amphoteric surfactant and chelating agent were monitored by NMR spectroscopy, including 13C chemical shift and lineshape analysis as well as 1H diffusometry.Findings: The study reveals that there is an interaction between the head group of the surfactant and the chelating agent forming oligomeric surfactant analogues with larger hydrophilic moieties, which results in smaller, more spherical micelles. The combined interactions provide possibilities for tuning the aggregation behavior of systems containing surfactants and chelating agents, and with that, the macroscopic properties of the system.

An unusual entrapment of ciprofloxacin by anionic-hydrophilic and cationic-hydrophilic mixed micellar system through complex formation

An unusual entrapment of ciprofloxacin by anionic-hydrophilic and cationic-hydrophilic mixed micellar system through complex formation

Concentration Dependent Asymmetric Synergy in SDS-DDAO Mixed Surfactant Micelles.

We investigate the structure and interactions of a model anionic/amphoteric mixed surfactant micellar system, namely, sodium dodecyl sulfate (SDS) and N,N-dimethyldodecylamine N-oxide (DDAO), employing SANS, FTIR, DLS, and pH measurements, in the range 0.1-100 mM total surfactant concentration and 0-100% DDAO. Increasing surfactant concentration is found to elongate the prolate ellipsoid micelles (RPolar ∼ 25-40 Å), accompanied by up to a 6-fold increase in micellar charge. The surfactant synergy, in terms of micellar charge and size, diffusion coefficient, solution pH, and headgroup interactions, was found to vary with concentration. At lower concentrations (≤50 mM), the SDS-DDAO ratio of maximum synergy is found to be asymmetric (at 65-85% DDAO), which is rationalized using regular solution theory, suggesting an equilibrium between Na+ dissociation, DDAO protonation, and counterion concentration. At higher concentrations, maximum synergy shifts toward the equimolar ratio. Overall, our study expands and unifies previous reports, providing a comprehensive understanding for this model, synergetic mixed micellar system.

Enhancing solubilization of Nebivolol hydrochloride through tuning pluronic F-127 with ionic Surfactants: An experimental and theoretical investigation

In the present work, the interaction of the antihypertensive drug Nebivolol hydrochloride (NBL) with nonionic surfactant pluronic F-127 (F-127) is investigated in an aqueous medium. Two ionic surfactants, viz., cationic, cetyl trimethyl ammonium bromide (CTAB) and anionic, sodium tetradecyl sulphate (STS) were added to F-127 to improve the physicochemical properties of the single micellar medium. The characterization techniques employed were, FTIR, UV–visible spectroscopy, dynamic light scattering, zeta potential, antioxidant, conductivity, and FESEM studies. The critical micellar concentration (CMC) of CTAB and STS are estimated from the conductivity experiments which is lowered due to the addition of F-127 and NBL. The lowering of CMC is attributed to the solubilization of NBL in the binary micellar mediums. The extent of binding of NBL in F-127, F-127 + CTAB, and F-127 + STS were quantified by determining the binding constant values using the Benesi–Hildebrand (B-H) plot from UV absorbance data. They were, 838.2 M−1 for F-127 1100.7 M−1 for F-127 + CTAB and 1836.5 M−1 for F-127 + STS systems. There was an increase in the size of the micelle due to the encapsulation of the drug in both binary micellar systems. The zeta potential (ZP) values displayed enhanced stability of the drug in binary micellar systems. The radical scavenging activity (RSA %) of NBL was estimated to be 16.5 % in F-127, 24.7 % in F-127 + CTAB, and 44.9 % in F-127 + STS systems. The encapsulation efficiency (EE %) for the above three systems were 14.7 %, 16.4 % and 18.5 %, respectively. The surface parameters and the interactions were verified through molecular docking studies. The results suggest that the properties of F-127 can be improved by tuning with ionic surfactants to solubilize NBL. To our knowledge, this is the first report of NBL solubilization in mixed micellar systems. Similar studies with other drug systems can be applied to get improved results.

Design of polymeric carriers to enhance antimicrobial photodynamic inactivation

Mixed polymeric micelles are a promising tool for the design of nanocarriers with pharmaceutical properties. These micellar systems allow reversing numerous properties of lipophilic drugs. Particularly, when applied to transport photosensitizers (PSs), they give rise to a wide variety of nanophotosensitizers (nPSs). These compounds are used to inactivate numerous bacteria resistant to conventional antibiotics. This research proposes the development of new mixed micelles, with better properties than simple micelles, for the trapping of Neutral Red (NR) and its monobrominated derivative (NRBr). Based on the combination of Pluronic P-123 with Pluronic F-108, Pluronic L-61 and Tween 80, 15 binary micellar systems were obtained. These mixed micelles presented a single population of homogeneous particles, with a diameter less than 70 nm. Moreover, several mixed micelles show smaller CMC than the simple system. These properties are predictors of high micellar stability and good anti-dilution properties, favoring their drug delivery applications. For these reasons, were loaded with NR and NRBr, showing good encapsulation efficiency. The 30 new nPSs presented an adequate size for pharmaceutical use and markedly enhanced the photochemical reactivity of the free PSs. Many of the mixed micellar systems showed greater production of singlet oxygen than the simple micelles of Pluronic P-123. Furthermore, all micellar systems increased the chemical stability of NRBr, which degrades in pH 7.4 buffer solution. Finally, all nPSs presented greater phototoxic activity against methicillin-resistant Staphylococcus aureus than free PSs. The nPSs formed by P-123: F-108 (90:10) + NR, P-123: F-108 (90:10) + NRBr, P-123: L-61 (80:20) + NRBr and P −123: T80 (80:20) + NRBr caused greater photodynamic inactivation of the microorganism than simple P-123 micellar systems. These nPSs could be considered excellent candidates for application in the treatment of infections caused by bacteria resistant to antibiotics.

Physicochemical investigation of encapsulation of antihypertensive drug captopril in mixed micellar system to enhance its delivery

This research work provides insight into the solubilization of a non-ionic drug captopril (CAP) in the micellar media of cationic surfactant cetyltrimethylammonium bromide (CTAB) and mixed micellar media of two nonionic surfactants Tween-80 and Triton X-100. CAP−surfactant interactions were analyzed by simple and differential absorption spectroscopy as well as by conductometry and the efficiency of the selected micellar system was assessed by calculating the values of partition coefficient (Kx), the free energy of partition (∆GP), binding constant (Kb) and the free energy of binding (∆Gb). Results from differential spectroscopy depicted a noteworthy increase in the solubilization of CAP with the addition of nonionic surfactants (Tween-80 and TX-100) in the micellar solution of CTAB. Furthermore, conductometric response of micellar media has been used to calculate the degree of dissociation (β), the free energy of micellization (∆Gm) thermodynamic parameters of micellization.

Scrutinizing micellar transitions and interfacial properties in mixed micelles comprising sodium dodecyl sulfate and sodium oleate: A tensiometric and scattering insight

Mixed micellar systems play a pivotal role in numerous scientific and industrial applications due to their inimitable solution properties and potential for enhancing solubilization and emulsification processes. The present study unveils the mixed micellization behavior of two anionically charged surfactants, sodium dodecyl sulfate (SDS) and sodium oleate (SO), in aqueous solutions through a combination of solution viscosity, tensiometric and small-angle neutron scattering (SANS) techniques. The dynamic changes in the interfacial properties of the mixed micellar system as a function of the SDS-to-SO ratio are evaluated from surface tension measurements. The results offer an insight into the formation of the stable mixed micelles with the alteration in the critical micelle concentration (CMC) as a function of the composition of both surfactants and the nature of the interaction. Surface tension data disclose the thermodynamic aspects of micelle formation and the influence of surfactant interactions on the surface activity of the system. Complementing the surface tension measurements, SANS analysis was conducted to clarify the structural aspects of the SDS-SO mixed micelles. SANS inferred the micellar size, shape, and aggregation number (Nagg), thereby shedding light on the nanoscale organization of the micellar aggregates in the aqueous solution. By combining SANS and surface tension data, a comprehensive understanding of the mixed micellization behavior of SDS and SO is achieved, addressing both interfacial and structural aspects. A computational simulation approach has also been employed to obtain the optimized parameters, which provide a better understanding of the correlation of SDS and SO molecular orbital energy levels. The results underscore the importance of surface tension and structural characterization techniques to comprehend the behavior of mixed micelles fully.

Evaluation of Anticancer Efficacy of D-α-Tocopheryl Polyethylene-Glycol Succinate and Soluplus® Mixed Micelles Loaded with Olaparib and Rapamycin Against Ovarian Cancer.

Ovarian cancer has the highest mortality rate and lowest survival rate among female reproductive system malignancies. There are treatment options of surgery and chemotherapy, but both are limited. In this study, we developed and evaluated micelles composed of D-α-tocopheryl polyethylene-glycol (PEG) 1000 succinate (TPGS) and Soluplus® (SOL) loaded with olaparib (OLA), a poly(ADP-ribose)polymerase (PARP) inhibitor, and rapamycin (RAPA), a mammalian target of rapamycin (mTOR) inhibitor in ovarian cancer. We prepared micelles containing different molar ratios of OLA and RAPA embedded in different weight ratios of TPGS and SOL (OLA/RAPA-TPGS/SOL) were prepared and physicochemical characterized. Furthermore, we performed in vitro cytotoxicity experiments of OLA, RAPA, and OLA/RAPA-TPGS/SOL. In vivo toxicity and antitumor efficacy assays were also performed to assess the efficacy of the mixed micellar system. OLA/RAPA-TPGS/SOL containing a 4:1 TPGS:SOL weight ratio and a 2:3 OLA:RAPA molar ratio showed synergistic effects and were optimized. The drug encapsulation efficiency of this formulation was >65%, and the physicochemical properties were sustained for 180 days. Moreover, the formulation had a high cell uptake rate and significantly inhibited cell migration (**p < 0.01). In the in vivo toxicity test, no toxicity was observed, with the exception of the high dose group. Furthermore, OLA/RAPA-TPGS/SOL markedly inhibited tumor spheroid and tumor growth in vivo. Compared to the control, OLA/RAPA-TPGS/SOL showed significant tumor inhibition. These findings lay a foundation for the use of TPGS/SOL mixed micelles loaded with OLA and RAPA in the treatment of ovarian cancer.

High-Yield Synthesis of Phosphatidylserine in a Well-Designed Mixed Micellar System.

A sustainable enzymatic system is essential for efficient phosphatidylserine (PS) synthesis in industrial production. Conventional biphasic systems face challenges such as excessive organic solvent usage, enzyme-intensive processes, and increased costs. This study introduces a novel approach using chitin nanofibrils (ChNFs) as an immobilization material for phospholipase D (PLD) in a mixed micellar system stabilized by the food-grade emulsifier sodium deoxycholate (SDC). The immobilized enzyme, ChNF-chiA1, was quickly prepared in a one-step process, eliminating the need for purification. By optimizing the reaction conditions, including l-Ser concentration (1.0 M), SDC concentration (10 mM), reaction time (8 h), and enzyme dosage (1.0 U), a remarkable PS yield of 96.74% was achieved in the solvent-free mixed micellar system. The catalytic efficiency of ChNF-chiA1 surpassed that of the free PLD-chiA1 biphasic system by 6.0-fold. This innovative and green biocatalytic technology offers a reusable solution for the high-value enzymatic synthesis of phospholipids, providing a promising avenue for industrial applications.

Unveiling the Role of Nonionic Surfactants in Enhancing Cefotaxime Drug Solubility: A UV-Visible Spectroscopic Investigation in Single and Mixed Micellar Formulations.

This study reports the interfacial phenomenon of cefotaxime in combination with nonionic surfactants, Triton X-100 (TX-100) and Tween-80 (TW-80), and their mixed micellar formulations. Cefotaxime was enclosed in a micellar system to improve its solubility and effectiveness. TX-100 and TW-80 were used in an amphiphilic self-assembly process to create the micellar formulation. The effect of the addition of TX-100, a nonionic surfactant, on the ability of TW-80 to solubilize the drug was examined. The values of the critical micelle concentration (CMC) were determined via UV-Visible spectroscopy. Gibbs free energies (ΔGp and ΔGb), the partition coefficient (Kx), and the binding constant (Kb) were also computed. In a single micellar system, the partition coefficient (Kx) was found to be 33.78 × 106 and 2.78 × 106 in the presence of TX-100 and TW-80, respectively. In a mixed micellar system, the value of the partition coefficient for the CEF/TW-80 system is maximum (5.48 × 106) in the presence of 0.0019 mM of TX-100, which shows that TX-100 significantly enhances the solubilizing power of micelles. It has been demonstrated that these surfactants are effective in enhancing the solubility and bioavailability of therapeutic compounds. This study elaborates on the physicochemical characteristics and solubilization of reactive drugs in single and mixed micellar media. This investigation, conducted in the presence of surfactants, shows a large contribution to the binding process via both hydrogen bonding and hydrophobic interactions.

Studies on anionic dye Eosin Y in mixed anionic micellar medium

Dye-Surfactant interactions in aqueous solution are important in industrial processes. Generally, dyes associate strongly with oppositely charged surfactants. But, similarly charged dye-surfactants are not preferred anticipating repulsion. To gain insight into the nature and extent of interaction between anionic dye Eosin Yellow (EY) and mixed anionic micellar system, this study was undertaken. Mixed micellar system comprised of anionic, Sodium dodecyl sulfate (SDS) and nonionic Pluronic L-35 (L-35). The characterizations employed were FTIR Spectroscopy, Conductivity, UV visible spectroscopy, Fluorescence spectroscopy and SEM studies. A red shift with enhancement of intensity was observed both in UV-absorption and emission spectra of EY when interacted with SDS + L-35 mixed micellar system. From the conductance measurements, the counter ion binding constant β was calculated. Subsequently, various thermodynamic parameters viz., ΔGm, ΔHm and ΔSm were evaluated using β. The Gibbs free energy of micellization, ΔGm was observed to be −4.56 kJ mol−1, −13.34 kJ mol−1 and −18.55 kJ mol−1 for SDS, SDS + L-35 and SDS + L-35 + EY respectively. The negative values of ΔGm are indicating the spontaneous binding occurring between EY and SDS + L-35. The SEM images revealed enlargement of grain size of the mixed micelle after encapsulation of EY. To the best of our knowledge this is the first report of anionic dye EY with an anionic mixed micellar system.

Binding and occupancy properties of gabapentin in mixed surfactant systems

AbstractThis research highlights the efficacy of mixed micellar systems as an innovative chemical formulation for improving the binding properties of active pharmaceutical drugs. The formulations based on the mole fraction were utilized for preparing mixed micelles with anionic sodium dioctyl sulfosuccinate (AOT) and sodium dodecyl sulphate (SDS). DLS measurements demonstrated the formation of small micelles and mixed micelles in SDS‐AOT combinations. A UV absorbance investigation demonstrated the effectiveness of the SDS‐AOT mixed micelles for determining the binding constant (Kb) and mean ion occupancy (i0) of the anticonvulsant gabapentin (GBP) drug. Kb values increased, but the occupancy (i) of GBP per micelle decreased by decreasing the mole fraction (α) of SDS from αSDS 0.9 to 0.1, predicting a shift in occupancy of drugs from the Palisade to the Stern layer. To get a better comprehension of micellization behavior and preferential interaction of the drugs under study, molecular docking studies were performed. According to the docking studies, the GBP displayed significant binding in the presence of SDS‐AOT when compared to pure SDS and AOT molecules. Ultimately, in pharmaceutical applications, mixed micelle played an important role in enhancing the binding and encapsulation efficiency of drugs.

Unraveling the impact of mono- or di-cationic ionic liquids on sodium deoxycholate aggregation and their interactions with ciprofloxacin

The interaction study between drugs and surfactants grasps significant attention in the field of pharmacology and for the advancement in pharmaceutical formulations. In this study, a mixed micellar system composed of sodium deoxycholate and either mono- or di-cationic ionic liquids was proposed. The main objective was to evaluate the aggregation behaviour of NaDC in the presence of mono or di-cationic ionic liquids and its ability to interact with ciprofloxacin. Although mixed micellar systems using imidazolium-based monocationic ionic liquids have been actively researched, the potential of di-cationic ionic liquid has not yet been explored. Therefore, in the present work imidazolium-based monocationic ionic liquid ([C10(mIm)]Br) and corresponding di-cationic ionic liquid ([C10(mIm)2]2Br) with bromide as a common anion were synthesized and evaluated their effect on the aggregation behavior of sodium deoxycholate. The aggregation behaviour of these micellar and mixed micellar systems was evaluated using conductivity and fluorescence experiments by determining the critical micellar concentration. Additionally, dynamic light scattering experiments were conducted to comprehend the size of the aggregates that are formed, and zeta potential was measured to determine the surface charge of the micelles which in turn helps to determine the stability of the aggregates formed. The interaction study between micellar or mixed micellar systems with ciprofloxacin was carried out using UV–visible spectroscopy. The Benesi-Hildebrand equation was employed to scrutinize the interaction parameters of micellar and mixed micellar systems with CIP, revealing that the mixed micellar system containing [C10(mIm)]Br exhibited the greatest binding affinity towards CIP.

Binary Pluronics based mixed micellar systems: Effective solution for improved solubilization of Biochanin A

The present work was carried out to appraise the solubilization of Biochanin (BCA), a natural hydrophobic drug in pure Pluronics (P84, P123 and F127) as well as binary mixed micelles (P84-P123 and F127-P123) followed by an interactional study using various state of art techniques. The critical micelle concentration (CMC) of binary mixtures P84-P123 and F127-P123 was found to be significantly lower than pure Pluronics justifying the candidature of mixed micelles (MMs) as a better solubilizer for BCA. UV–visible studies revealed the enhanced solubility of BCA in P84-P123 (1:2) MMs (3.51 ± 0.087 mg/mL) and F127-P123 (1:2) MMs (2.94 ± 0.046 mg/mL) as compared to micelles of pure Pluronics (10% w/v), P84 (2.25 ± 0.039 mg/mL) and F127 (1.12 ± 0.036 mg/mL). Differential pulse voltammetry (DPV) results demonstrated significantly superior binding of BCA with P84-P123 (1:2) MM (Ka = 2.60 × 105 M−1) as compared to pure P84 (Ka = 1.415 × 105 M−1). Mixed micellization (P84-P123 (1:2)) leads to increase in micellar hydrodynamic diameter (Dh = 16.09 nm) as compared to pure Pluronic P84 micelles (Dh = 15.71 nm) which was further amplified (Dh = 17.69 nm) after BCA loading. Different formulations of pure and MMs were subjected to in vitro drug release and MMs were found to slow down BCA release as compared to pure Pluronics (P84, P123). The results obtained in this study proved that P84-P123 (1:2) MMs are superior and more effective for the solubilization of BCA than pure and other MMs. Thus, the examined MMs hold the potential for advancing the development of solubilization techniques for other hydrophobic drugs with significant pharmacological value.

Analyzing the modulations induced in the mixed micellar behavior of 1-alkyl-3-butylimidazolium based surface-active ionic liquids with an antibiotic drug in aqueous media

Abstract The study aims to scrutinize the mixed micellization and interfacial behavior of two 1-alkyl-3-butylimidazolium based surface-active ionic liquids (SAILs) i.e., 1-decyl-3-butylimidazolium bromide [C10bim][Br] and 1-tetradecyl-3-butylimidazolium bromide [C14bim][Br] under the influence of streptomycin sulphate (SS) drug in 5 mM concentration in aqueous media. Imidazolium-based SAILs have unique physicochemical properties and greater surface activity than conventional surfactants, which allows them to increase drug permeability, making them better drug carriers than currently available formulations. To fully utilize [C14bim][Br] and [C10bim][Br] in drug delivery applications, deep insight into the interactions occurring in the mixed micellar [C10bim][Br]/[C14bim][Br] systems in the drug’s presence are necessary to be examined. Thus, the study is conducted using conductivity and surface tension measurement techniques to fully exploit the self-assembly, micellization behavior and interactions occurring in the pure and mixed micellar system of [C10bim][Br]/[C14bim][Br] in water and 5 mM of SS solution in aqueous media. For this, various thermodynamic, surface-active and mixed micellar parameters of micellization have been calculated and analyzed with respect to change in mole fraction, temperature and addition of SS in solution.

Development and evaluation of azithromycin dihydrate in single and binary micellar mediums

Azithromycin (AZI) has poor aqueous solubility and very low bioavailability. In this study, two nonionic polymeric surfactants, namely Pluronic L-35, and Pluronic P-123, and their binary micelle was used for entrapment of drug AZI. The drug-encapsulated micelles were characterized by UV-spectrophotometry, FTIR, Cloud point, Partition coefficient, and antibacterial studies. We observed improved solubilization of the drug AZI in the binary micellar formulation than in their single micellar systems. The FTIR studies inferred that there is a stable, strong bond formation of the drug AZI with the binary micelle. The partition coefficient values too pointed towards higher solubility of drug AZI in mixed micellar systems as compared to single micellar systems. The free energy of micellization ∆Gomic as determined from the partition coefficient displayed negative values for all three systems indicating spontaneous binding between the drug AZI with the polymeric micellar systems. The highest negative value (-3192.6 kJ/mol) for AZI in the binary system compared to AZI-L-35 (-1620.3 kJ/mol) and AZI-P-123 (-2752.8 kJ/mol) concludes that the drug AZI is better partitioned in the binary micellar system than in the two single micellar solutions. This study can be considered as a potential solubilizing medium for the drug AZI. This is probably the first report of AZI in binary micellar solution.

Deciphering the influence of salt on the mixed micellization of drug Domiphen Bromide and tri-substituted SAIL [C12bmim][Br] mixture

The mixed micellization between amphiphilic drug Domiphen Bromide (DB) and tri-substituted SAIL 1-dodecyl-2,3-dimethylimidazolium bromide [C12bmim][Br] in absence/attendance of 10 mM NaH2PO4.2H2O has been explored through conductivity and surface tension measurements at various temperatures. Conductance was used to determine the critical micelle concentration (cmc) and other thermodynamic parameters while the interfacial parameters were derived from the surface tension which were helpful in figuring out the phenomenon that was occurring at the interface. The mixed micellar system has been investigated using three distinct theoretical models: the Rubingh model, the Motomura model, and the Rodenas model. The obtained results i.e. cmcid >cmcexp implies synergism between the studied components, DB and [C12bmim][Br]. Larger negative values ofβ indicated a highly effective interaction between the two components. Further influence of salt addition on the mixed system has also been discussed. The negative magnitudes of the Gibbs free energy of micellization (ΔGm0) between the two amphiphiles investigated suggested the creation of spontaneous mixed micelles.