Unraveling the Role of Polyoxometalates-Based Superchaotropes on the Photophysics of Organic Molecules and Modulation of Water Dynamics in a Hydrophilic Block Copolymer Solution.

Polyoxometalates (POMs) are composed of nanometric metal-oxide anions and have rich solution chemistry. In this class, Keggin POMs have been identified as the most influential inorganic additives for aqueous nonionic soft matter systems. POMs being at the borderline of classical ions and charged colloids possess fascinating solution properties; the present work aims to delve deeper into the interactions between nanoions and nonionic soft matters from a spectroscopic point of view.

Supramolecular Gelation Based on Native Amino Acid Tyrosine and Its Charge-Transfer Complex Formation.

Self-assembly of amino acids and short-peptide derivatives attracted significant curiosity worldwide due to their unique self-assembly process and wide variety of applications. Amino acid is considered one of the important synthons in supramolecular chemistry. Self-assembly processes and applications of unfunctionalized native amino acids have been less reported in the literature.

Probing Interparticle Interaction and Ordering in Silica-Pluronic-Based Solutions and Emulsions by Small-Angle Scattering Techniques.

Introduction of non-DLVO forces by nonionic surfactants brings about fascinating changes in the phase behavior of silica nanosuspensions. We show here that alterations in the interaction and wetting properties of negatively charged silica nanoparticles (Ludox® LS) in the presence of polyethylene oxide-polypropylene oxide-polyethylene oxide-based triblock copolymers called Pluronics lead to the formation of stable o/w Pickering emulsions and interparticle attraction-induced thermoresponsive liquid-liquid phase separations. The results make interesting comparisons with those reported for Ludox® TM nanosuspensions comprising larger silica nanoparticles.

ct-DNA compaction by nanoparticles formed by silica and gemini surfactants having hydroxyl group substituted spacers: In vitro, in vivo, and ex vivo gene uptake to cancer cells.

Hybrid nanoparticles formed by Silica (SiO) coated with cationic gemini surfactants with variable hydroxyl group substituted spacers, 12-4(OH)-12,2Br and 12-4(OH)-12,2Br have shown a great extent of compaction of calf thymus DNA (ct-DNA) compared to conventional counterpart cationic surfactant, dodecyl trimethylammonium bromide (DTAB). Study shows not only the hydrophobicity of the spacer but also the hydrogen bonding interactions between the hydroxyl group substituted spacer and DNA have a great role in DNA compaction. 12-4(OH)-12,2Br is more efficient in compacting ct-DNA compared to 12-4(OH)-12,2Br due to the stronger binding of the former with ct-DNA than the latter.

Deciphering the Influence of Zwitterionic Surfactants on Pluronic Co-assemblies: A Synergistic Odyssey through Spectroscopic, Microscopic, and Scattering Techniques.

Fundamental investigations into the photophysical properties and microenvironmental features of pluronic-zwitterionic surfactant mixed assemblies are essential for advancing our understanding of molecular interactions at the nanoscale, setting the stage for innovative solutions in drug delivery, diagnostics, and other applications of pluronic-zwitterionic surfactant assemblies. This investigation explores the intricate photophysics of pluronic-zwitterionic surfactant mixed assemblies, utilizing the twisted intramolecular charge transfer state forming styryl dye trans-2-[(4-dimethylamino) styryl] benzothiazole as a probe. By comparing the behaviors of two distinct poly(ethylene oxide)--poly(propylene oxide)--poly(ethylene oxide) block copolymers with block composition of (PEO)(PPO)-(PEO) [F108] and (PEO)-(PPO)-(PEO) [F127] at concentrations of 5 and 10 wt %, this study systematically examines the impact of the addition of zwitterionic surfactants.

Competing Effects of Temperature and Polymer Concentration on Evolution of Re-entrant Interactions in the Nanoparticle-Block Copolymer System.

An interesting evolution of the re-entrant interaction has been observed in an anionic silica nanoparticle (NP)-block copolymer (P85) dispersion due to mutually competing effects of temperature and polymer concentration. It has been demonstrated that a rise in the temperature leads to an evolution of attraction in the system, which interestingly diminishes on increasing the polymer concentration. Consequently, the system exhibits a re-entrant transition from repulsive to attractive and back to repulsive at a given temperature but with respect to the increasing polymer concentration, within a selected region of concentration and temperature.

Impact of Ionic Liquids on the Physicochemical Behavior of Vesicles.

The effects of two ionic liquids (ILs), 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF) and 1-butyl-1-methyl pyrrolidinium tetrafluoroborate ([bmp]BF), on a mixture of phospholipids (PLs) 1,2-dipalmitoyl--glycero-3-phosphatidylcholine (DPPC), 1,2-dipalmitoyl--glycero-3-phosphoethanolamine (DPPE), and 1,2-dipalmitoyl--glycero-3-phosphoglycerol (DPPG) (6:3:1, M/M/M, 70% PL) in combination with 30 mol % cholesterol (CHOL) were investigated in the form of a solvent-spread monolayer and bilayer (vesicle). Surface pressure (π)-area () isotherm studies, using a Langmuir surface balance, revealed the formation of an expanded monolayer, while the cationic moiety of the IL molecules could electrostatically and hydrophobically bind to the PLs on the palisade layer. Turbidity, dynamic light scattering (size, ζ-potential, and polydispersity index), electron microscopy, small-angle X-ray/neutron scattering, fluorescence spectroscopy, and differential scanning calorimetric studies were carried out to evaluate the effects of IL on the structural organization of bilayer in the vesicles.

Evolution of the structure and interaction in the surfactant-dependent heat-induced gelation of protein.

The addition of a surfactant and/or an increase in temperature disrupt the native structure of proteins, where high temperature further results in protein gelation. However, in a mixed protein-surfactant system, surfactant concentration and temperature have been observed to exhibit both mutually associative and counter-balancing effects towards heat-induced gelation of protein-surfactant dispersion. This study is conducted on globular bovine serum albumin (BSA) protein and cationic surfactant dodecyl trimethyl ammonium bromide (DTAB), which interact strongly owing to their oppositely charged nature.

Molecular Insights into the Conformational and Binding Behaviors of Human Serum Albumin Induced by Surface-Active Ionic Liquids.

Extensive research has been carried out to investigate the stability and function of human serum albumin (HSA) when exposed to surface-active ionic liquids (SAILs) with different head groups (imidazolium, morpholinium, and pyridinium) and alkyl chain lengths (ranging from decyl to tetradecyl). Analysis of the protein fluorescence spectra indicates noticeable changes in the secondary structure of HSA with varying concentrations of all SAILs tested. Helicity calculations based on the Fourier transform infrared (FTIR) data show that HSA becomes more organized at the micellar concentration of SAILs, leading to an increased protein activity at this level.

Self-assembly of choline-based surface-active ionic liquids and concentration-dependent enhancement in the enzymatic activity of cellulase in aqueous medium.

The micellization of choline-based anionic surface-active ionic liquids (SAILs) having lauroyl sarcosinate [Sar], dodecylsulfate [DS], and deoxycholate [Doc] as counter-ions was investigated in an aqueous medium. Density functional theory (DFT) was employed to investigate the net interactional energy (), extent of non-covalent interactions, and band gap of the choline-based SAILs. The critical micelle concentration (cmc) along with various parameters related to the surface adsorption, counter-ion binding (), and polarity of the cores of the micelles were deduced employing surface tension measurements, conductometric titrations and fluorescence spectroscopy, respectively.

Metal organic framework-based polymeric hydrogel: A promising drug delivery vehicle for the treatment of breast cancer.

The constraints associated with current cancer therapies have inspired scientists to develop advanced, precise, and safe drug delivery methods. These delivery systems boost treatment effectiveness, minimize harm to healthy cells, and combat cancer recurrence. To design advanced drug delivery vehicle with these character, in the present manuscript, we have designed a self-healing and injectable hybrid hydrogel through synergistically interacting metal organic framework, CuBTC with the poly(vinyl alcohol) (PVA).

Impact of formulation parameters on self-assembled liposomes (LeciPlex® III): A detailed investigation.

The present study investigated the feasibility of fabricating self-assembled liposomes, LeciPlex®, a phospholipid-based vesicular nanocarrier using cationic, anionic, and nonionic stabilizers. The phospholipid investigated was soy phosphatidylcholine and the nano-precipitation method based on solvent diffusion was applied as the fabrication technique of liposomes in this study. The effects of various formulation variables, such as lipid and stabilizer concentration, total solid concentration, and solvent type on the self-assembly of vesicles were studied for physical characterization including particle size analysis, differential scanning calorimetry, viscosity, optical transmittance, transmission electron microscopy, and small angle neutron scattering.

Multifunctional Ionic Hydrogel-Based Transdermal Delivery of 5-Fluorouracil for the Breast Cancer Treatment.

Transdermal drug delivery systems (TDDS) are a promising and innovative approach for breast cancer treatment, offering advantages such as noninvasiveness, potential for localized and prolonged drug delivery while minimizing systemic side effects through avoiding first-pass metabolism. Utilizing the distinctive characteristics of hydrogels, such as their biocompatibility, versatility, and higher drug loading capabilities, in the present work, we prepared ionic hydrogels through synergistic interaction between ionic liquids (ILs), choline alanine ([Cho][Ala]), and choline proline ([Cho][Pro]) with oleic acid (OA). ILs used in the study are biocompatible and enhance the solubility of 5-fluorouracil (5-FU), whereas OA is a known chemical penetration enhancer.

Structural Rearrangement Followed by Entrapment of Subnanometer Building Blocks of Iron Oxyhydroxide in Aqueous Iron Chloride Solutions.

Iron oxyhydroxide, a natural nanophase of iron found in the environment, plays a crucial role in regulating surface and groundwater composition. Recent research proposes that within the nonclassical prenucleation cluster growth model, subnanometer-sized clusters (olation clusters/Fe δ-Keggin oxolation clusters) might act as the prenucleation clusters (PNCs) of ferrihydrite or iron oxyhydroxide solid phase. However, these clusters are difficult to characterize as they are only observable momentarily in low-pH, high-Fe concentration solutions before agglomerating into extended solids, keeping the controversy over the true nature of the PNCs alive.

Structural and therapeutic properties of salicylic acid-solubilized Pluronic solutions and hydrogels.

Salicylic acid (SA) finds extensive applications in the treatment of rheumatic and skin diseases because of its analgesic, anti-inflammatory and exfoliating properties. As it is lipophilic in nature, there is a need for appropriate delivery systems to harness these properties for different applications. Herein, we examined the suitability of Pluronic P123/F127 micellar systems as delivery media by investigating the structural, flow and antimicrobial properties of P123/F127-SA solutions and hydrogels using DLS, SANS, rheological and zone inhibition measurement techniques.

Cleavable Amphiphilic Biocides with Ester-Bearing Moieties: Aggregation Properties and Antibacterial Activity.

The rise of multidrug-resistant bacterial infections and the dwindling supply of newly approved antibiotics have emerged as a grave threat to public health. Toward the ever-growing necessity of the development of novel antimicrobial agents, herein, we synthesized a series of cationic amphiphilic biocides featuring two cationic headgroups separated by different hydrophobic spacers, accompanied by the inclusion of two lipophilic tails through cleavable ester functionality. The detailed aggregation properties offered by these biocides were investigated by small-angle neutron scattering (SANS) and conductivity.

Additive-anchored thermoresponsive nanoscale self-assembly generation in normal and reverse Tetronics®.

Self-assembly of ethylene oxide (EO)-propylene oxide (PO)-based star-shaped block copolymers (BCPs) in the presence of different kinds of additives is investigated in an aqueous solution environment. Commercially available four-armed BCPs, namely Tetronics® (normal: T904 with EO as the terminal end block; and reverse: T90R4 with PO as the terminal end block), each with 40%EO, are used. The effect of various additives such as electrolytes (NaCl and NaSO), nonelectrolyte polyols (glucose and sorbitol), and ionic surfactants ( anionic-sodium dodecyl sulfate (SDS), cationic-dodecyltrimethylammonium bromide (DTAB) and zwitterionic dodecyldimethylammonium propane sulfonate (CPS)) on these BCPs is examined to observe their influence on micellization behaviour.

Mixed Pluronic/lecithin micelles formulation for oral bioavailability of candesartan cilexetil drug: characterization and pharmacokinetic investigations.

Objective: This study aimed to develop a mixed polymeric micelle formulation incorporating candesartan cilexetil (CAND) drug to enhance its oral bioavailability for the better treatment of hypertension.

Methods: A Box-Behnken design was utilized to optimize the CAND-incorporated mixed polymeric micelles formulation (CAND-PFLC) consisting of Pluronics (P123 and F68) and lecithin (LC). The optimized CAND-PFLC micelles formulation was characterized for size, shape, zeta potential, polydispersity index (PDI), and entrapment efficiency (%EE).

Molecular insights into the aggregation and solubilizing behavior of biocompatible amphiphiles Gelucire® 48/16 and Tetronics® 1304 in aqueous media.

A comparative analysis of the micellar and solubilizing properties of two polyethylene glycol (PEG)-based amphiphilic biocompatible excipients: Gelucire® 48/16 (Ge 48/16) and Tetronics® 1304 (T1304), in the presence and absence of salt, was conducted. As there is a dearth of research in this area, the study aims to shed light on the behavior of these two nonionic surfactants and their potential as nanocarriers for solubilizing pharmaceuticals. Various techniques such as cloud point (CP), dynamic light scattering (DLS), small-angle neutron scattering (SANS), Fourier transform infrared spectroscopy (FT-IR), UV spectrophotometry, and high-performance liquid chromatography (HPLC) were employed.

Salt induced micellization conduct in PEO-PPO-PEO-based block copolymers: a thermo-responsive approach.

The nanoscale self-assembly behavior in ethylene oxide (EO) and propylene oxide (PO)-based block copolymers (BCPs) commercially available as Pluronics®: L44 (PEO-PPO-PEO) and F77 (PEO-PPO-PEO) is put forth in aqueous solution and in the presence of sodium salts NaCl and NaSO. The moderate hydrophilicity of L44 is attributed to its low molecular weight PPO segment, while the high percentage of PEO content in F77 contributes to its extreme hydrophilicity. The impact of sodium salts (NaCl and NaSO) on the self-assembly is investigated to understand their influence and role in micellization, by employing various physicochemical techniques such as phase behavior conduct, calorimetry, tensiometry, scattering, and spectral analysis.

Compaction of Calf Thymus DNA by a Potential One-Head-Two-Tail Surfactant: Properties of Nanomaterials and Biological Testing for Gene Delivery.

A one-head-two-tail cationic surfactant, Dilauryldimethylammonium bromide (DDAB) has shown a great extent of calf thymus DNA (ct-DNA) compaction being adsorbed on the surfaces of negatively charged SiO nanoparticles (NPs). DDAB molecules show high adsorption efficiency and induce many positive surface charges per-unit surface area of the SiO NPs compared to cationic Gemini (12-6-12) and conventional (DTAB) surfactants in an aqueous medium at pH 7.4, as evident from zeta potential and EDAX data.

Mixed Aggregates of Surface-Active Ionic Liquids and 14-2-14 Gemini Surfactants in an Aqueous Medium as Fluid Scaffolds for Enzymology of Cytochrome-c.

The aggregation behavior of the surface-active ionic liquid (SAIL), 3-(2-(hexadecyloxy)-2-oxoethyl)-1-methyl-1-imidazol-3-ium chloride, [CEmim][Cl], and a gemini surfactant (GS) (14-2-14) in the whole mole fraction range has been investigated in an aqueous medium employing various techniques. Experimentally obtained values of critical aggregation concentration (cac) are in good agreement with the theoretical cac values obtained using Clint's equation. Rubingh's model has been employed to evaluate the extent of synergistic interactions between two components, which has been found to be dependent upon the composition of a mixture of surfactants.

Investigating the Influence of Aromatic Counterions on the Micellar Structure and Aggregation Behavior of Morpholinium-Based Surface-Active Ionic Liquids in an Aqueous Solution.

Two morpholinium-based surface-active ionic liquids (SAILs) with aromatic counterions were synthesized, namely, -dodecyl--methylmorpholinium salicylate [Cmmor][Sal] and -dodecyl--methylmorpholinium 3-hydroxy-2-naphthoate [Cmmor][3--2-], and explored their aggregation behavior in aqueous solutions systematically. Electrical conductivity, small-angle neutron scattering (SANS), surface tension (ST), and UV-vis spectroscopy measurements were employed to determine various thermodynamic, micellar, and interfacial parameters, like the degree of counterion binding (β), critical micelle concentration (CMC), minimum area per molecule (), surface excess concentration (Γ), standard Gibbs free energy of adsorption (Δ), aggregation number (), standard Gibbs free energy of micellization (Δ), standard enthalpy of micelle formation (Δ), and the standard entropy of micellization (Δ) in an aqueous solution. Incorporating the aromatic counterions favors significantly excellent micellization properties over conventional halogenated SAILs such as [Cmmor][Br].