Types Of Micelles Research Articles

Ultrastable and Redispersible Zwitterionic Bottlebrush Micelles for Drug Delivery.

Bottlebrush copolymers are increasingly used for drug delivery and biological imaging applications in part due to the enhanced thermodynamic stability of their self-assemblies. Herein, we discuss the effect of hydrophilic block chemistry on the stability of bottlebrush micelles. Amphiphilic bottlebrushes with zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and nonionic polyethylene glycol (PEG) hydrophilic blocks were synthesized by "grafting from" polymerization and self-assembled into well-defined spherical micelles. Colloidal stability and stability against disassembly were challenged under high concentrations of NaCl, MgSO4, sodium dodecyl sulfate, fetal bovine serum, and elevated temperature. While both types of micelles appeared to be stable in many of these conditions, those with a PMPC shell consistently surpassed their PEG analogs. Moreover, when repeatedly subjected to lyophilization/resuspension cycles, PMPC micelles redispersed with no apparent variation in size or dispersity even in the absence of a cryoprotectant; PEG micelles readily aggregated. The observed excellent stability of PMPC micelles is attributed to the low critical micelle concentration of the bottlebrushes as well as to the strong hydration shell caused by ionic solvation of the phosphorylcholine moieties. Zwitterionic micelles were loaded with doxorubicin, and higher loading capacity/efficiency, as well as delayed release, was observed with increasing side-chain length. Finally, hemocompatibility studies of PMPC micelles demonstrated no disruption to the red blood cell membranes. The growing concern regarding the immunogenicity of PEG-based systems propels the search for alternative hydrophilic polymers; in this respect and for their outstanding stability, zwitterionic bottlebrush micelles represent excellent candidates for drug delivery and bioimaging applications.

Polymeric Micelles in Colorectal Cancer Therapy: A Comprehensive Review of Nano-drug Delivery Strategies, Copolymer Types, Physicochemical Characteristics, and Therapeutic Applications.

Polymeric micelles are becoming the method of choice for a nano-drug delivery system, especially in colorectal cancer treatment. These tiny structures have become popular for their amazing qualities that make drug delivery more efficient and therapies better. Colorectal cancer, also known as colon cancer, is one of the most common and deadly cancers in the world. Traditional chemotherapy is good, but it has big downsides, like harming other parts of the body and making people sick all over. Polymeric micelles give a new way to fix these problems by being easier on the body, breaking down naturally, and staying in the blood longer. The polymeric micelles, which are loaded with drugs, are sheltered within the tumor, which leads to a reduction in off-site effects and an increase in the targeting and accumulation of chemotherapeutics at the cancer site. This review paper elaborates on the current status of polymeric micelles as a method for nano-drug delivery for chemotherapy, emphasizing their efficacy in managing cancer. The paper also talks about the various types of copolymers that are used to create polymeric micelles, the different types of micelles, their physicochemical properties, the preparation process, characterization, and their application in cancer diagnostics.

A Study of the Micellar Formation of N-Alkyl Betaine Ethyl Ester Chlorides Based on the Physicochemical Properties of Their Aqueous Solutions.

In this study, a series of four surface-active compounds-N-alkyl betaine ethyl ester chlorides, CnBetC2Cl-were synthesized and characterized in aqueous solutions. As with other alkyl betaines, these amphiphiles can be practically used, for example, as co-surfactants and/or solubility enhancers acting according to hydrotropic or micellar mechanisms, depending on the alkyl chain length in the amine. We focused on the representatives of the medium alkyl chain length (C6-C12) to find the dependence between the alkyl chain length in N-alkyl betaine ethyl ester chlorides and the surface, volumetric, acoustic, and viscometric properties of their solutions. Ethyl esters, the derivatives of amino acids, were chosen to increase functionality and take advantage of possible hydrolysis in solutions at higher pH, which is also a key parameter in biodegradability. The micellization parameters were calculated based on the physicochemical characteristics. We focused our interest on the ester with a dodecyl substituent since we can compare and discuss its properties with some other C12 representatives that are available in literature. Surprisingly, its micellization characteristic is almost temperature-independent in the investigated temperature range, t = (15-45) °C. Particularly interesting are the results of dynamic light scattering (DLS), which show that the changes in physicochemical parameters of the C12 homolog around the CMC are caused by the two types of micelles of different sizes present in solutions.

Nanomedicine for cancer targeted therapy with autophagy regulation.

Nanoparticles have unique physical and chemical properties and are currently widely used in disease diagnosis, drug delivery, and new drug development in biomedicine. In recent years, the role of nanomedical technology in cancer treatment has become increasingly obvious. Autophagy is a multi-step degradation process in cells and an important pathway for material and energy recovery. It is closely related to the occurrence and development of cancer. Because nanomaterials are highly targeted and biosafe, they can be used as carriers to deliver autophagy regulators; in addition to their favorable physicochemical properties, nanomaterials can be employed to carry autophagy inhibitors, reducing the breakdown of chemotherapy drugs by cancer cells and thereby enhancing the drug's efficacy. Furthermore, certain nanomaterials can induce autophagy, triggering oxidative stress-mediated autophagy enhancement and cell apoptosis, thus constraining the progression of cancer cells.There are various types of nanoparticles, including liposomes, micelles, polymers, metal-based materials, and carbon-based materials. The majority of clinically applicable drugs are liposomes, though other materials are currently undergoing continuous optimization. This review begins with the roles of autophagy in tumor treatment, and then focuses on the application of nanomaterials with autophagy-regulating functions in tumor treatment.

Core Cross‐Linking Enhances the Anti‐Inflammatory Performance of Oxidation‐Sensitive Polymeric Micelles

AbstractNanomaterials able to scavenge biologically relevant oxidants (reactive oxygen species, ROS) can directly act as anti‐inflammatory agents. Here, micelles made of amphiphilic poly(ethylene glycol)(PEG)‐polysulfide block copolymers are focused on; the polysulfide blocks are responsible of ROS‐scavenging and are composed of propylene sulfide and ethylene sulfide units in ratios of 20:0, 15:5, 10:10. These polymers can be intramicellarly cross‐linked through thermal thiol‐yne reaction of terminal alkynes (trithiol cross‐linker). Self‐assembled and cross‐linked micelles are virtually identical in size and scavenging kinetics, but greatly differ in stability against dilution (critical aggregation concentration (CAC) respectively of ≈0.1 and <0.01 mg mL−1) and in the final state after oxidation (soluble polymers vs cross‐linked nanoparticles). Most importantly, self‐assembled micelles have significant toxicity and damage cell membranes already at 0.5 mg mL−1, which seriously hampers their anti‐inflammatory activity. On the contrary, cross‐linked micelles do not appreciably harm cells at least up to 1 mg mL−1, and effectively inhibit the production of inflammatory cytokines in activated macrophages. In this study, a detailed interpretation of the morphological evolution of the two types of micelles during oxidation is provided and it is proved that core cross‐linking significantly widens the therapeutic window.

Synergistic effects of surfactant and polymer on the viscosity and oil displacement efficiency

For chemical flooding, choosing suitable surfactant and polymer mixture to optimize the viscosity and interfacial tension is an important procedure for preparing the combination flooding system. In this work, a systematic study was conducted on the properties of the surfactant/polymer mixed solution, involving viscoelasticity, oil/water interfacial tension and oil displacement efficiency. Zwitterionic-anionic surfactant mixture (HDPS-SDS) was chosen to show the effect of concentration and micelles type. Partially hydrolyzed polyacrylamide (HPAM) and hydrophobically associating polymer (HPOC) were selected to show the effect of polymer concentration and type. It has been found that for polymer solutions, adding HDPS-SDS reduces the oil/water interfacial tensions to the magnitude of 10−2 mN·m−1, but negative synergistic effect for spherical micelles and positive synergistic effect for wormlike micelles on viscosity are observed. For wormlike micelles solutions, adding HPAM or HPOC increases the viscosity. Moreover, the positive synergistic effect on viscosity by HPOC is far stronger than that of HPAM, and the viscosity of wormlike micelle solution can be reinforced by adding a small amount of HPOC. The synergistic effect on viscosity will also affect the oil displacement efficiency of the surfactant/polymer mixed system. For example, the enhanced oil displacement efficiency E of surfactant/polymer flooding unexpectedly reduces with adding spherical micelles formed by low concentration HDPS-SDS to 1500 mg L−1 HPOC solutions. Whereas the enhanced oil displacement efficiency E of wormlike micelles/polymer flooding reaches 28.8% with adding 800 mg L−1 HPOC to 5500 mg L−1 HDPS-SDS wormlike micelles solutions.

Enhanced ASO-Mediated Gene Silencing with Lipophilic pH-Responsive Micelles.

Herein, we examine the ASO-mediated gene silencing efficiency of pH-responsive micelles, by incorporating 2-(diisopropylamino)ethyl methacrylate (DIP) into the micelle core and comparing physical and biological properties with non-pH-responsive micelles. Additionally, the lipophilic effect of the micelle cores was examined in both types of micelles. Varying lipophilicity was achieved by varying alkyl monomer chain lengths─butyl (4), lauryl (12), and stearyl (18) methacrylate. Each of the micelles formed within our family offered the added benefit of well-defined and uniform templates for loading antisense oligonucleotide (ASO) payloads. Overall, the micelles followed previously established trends of outperforming their linear polymer (nonmicelle) analogs and ASO only control. More specifically, the highest performing micelles were the pH-responsive micelles with longer alkyl chains or higher lipophilicity─D-DIP+LMA and D-DIP+SMA (∼90% silencing). These two micelles demonstrated silencing efficiencies similar to Jet-PEI and Lipofectamine 2000 and caused lower toxicity than Lipofectamine 2000. The shortest alkyl chain pH-responsive micelle, D-DIP+BMA (64%), displayed strong gene silencing similar to that about that of its non-pH-responsive micelle, D-BMA (68%), and the pH-responsive micelle without an alkyl chain incorporated, D-DIP (59%). This work illuminates a minimum alkyl chain length dependence to allow gene silencing within our micelle family. However, including only longer alkyl chains into the micelle core without the pH-responsive unit DIP had a hindering effect, thus demonstrating the requirement of the DIP unit when including longer alkyl chain lengths. This work demonstrates the exemplary gene silencing efficiencies of polymeric micelles and uncovers the relationship between pH responsiveness and performance with lipophilic polymer micelles for enhancing ASO-mediated gene silencing.

Closo-dodecaborate-based dianionic surfactants with distorted classical morphology: Synthesis and atypical micellization in water

HypothesisTo challenge the classical concept of step-like micellization of ionic surfactants with singular critical micelle concentration, novel amphiphilic compounds with bulky dianionic head and the alkoxy tail connected via short linker, which can complex sodium cations, were synthesized in the form of disodium salts. ExperimentThe surfactants were synthesized by opening of a dioxanate ring attached to closo-dodecaborate by activated alcohol, which allows for attachment of alkyloxy tails of desired length to boron cluster dianion. The synthesis of the compounds with high cationic purity (sodium salt) is described. Self-assembly of the surfactant compound at air/water interface and in bulk water was studied by tensiometry, light and small angle X-ray scattering, electron microscopy, NMR spectroscopy, MD simulations and by isothermal titration calorimetry, ITC. The peculiarities in the micelle structure and formation were revealed by thermodynamic modelling and MD simulations of the micellization process. FindingsIn an atypical process, the surfactants self-assemble in water to form relatively small micelles, where the aggregation number is decreasing with the surfactant concentration. The extensive counterion binding is a key characteristic of the micelles. The analysis strongly indicates complex compensation between the degree of bound sodium ions and the aggregation number. For the first time, a three-step thermodynamic model was used to estimate the thermodynamic parameters associated with micellization process. Diverse micelles differing in size and counterion binding can (co–)exist in the solution over the broad concentration and temperature range. Thus, the concept of step-like micellization was found inappropriate for these types of micelles.

Validation of an MD simulation approach for electrical field responsive micelles and their application in drug delivery

In the current work, a new type of micelle is designed that has active connectivity in respond to exterior stimulus and the desired water solubility. Two end-ornamented homopolymers, polystyrene-beta-cyclodextrin (PS-β-CD) and polyethylene oxide-ferrocene (PE-FE), can aggregate as a supramolecular micelle (PS-β-CD/PE-FE) by the guest–host interactions. Our results showed that the Lennard–Jones and hydrophobic interactions are the main powerful forces for the micelle formation process. It was found that the electrical field plays a role as a driving force in the reversible assembly-disassembly of the micellar system. Moreover, for the first time, we examined the PS-β-CD/PE-FE micelle interaction as a drug delivery system with anastrozole (ANS) and mitomycin C (MIC) anti-cancer drugs. The investigation of the total energy between PS-β-CD/PE-FE micelle and drugs predicts the drug adsorption process as favorable (Etotal = − 638.67 and − 259.80 kJ/mol for the Micelle@ANS and Micelle@MIC complexes, respectively). Our results offer a deep understanding of the micelle formation process, the electrical field-respond, and drug adsorption behaviors of the micelle. This simulation study has been accomplished by employing classical molecular dynamics calculation.

Preparation of reversible cross-linked amphiphilic polymeric micelles with pH-responsive behavior for smart drug delivery.

A new type of reversible cross-linked and pH-responsive polymeric micelle (PM), poly[polyethylene glycol methacrylate-co-2-(acetoacetoxy)ethyl methacrylate]-b-poly [2-(dimethylamino)ethyl methacrylate] [P(PEGMA-co-AEMA)-b-PDMAEMA], was synthesized for targeted delivery of curcumin. After reversible cross-linking of the micellar shell, the PMs with a typical core-shell structure exhibited excellent stability against extensive dilution and good reversibility of pH-responsiveness in solutions with different pH values. P(PEGMA9-co-AEMA6)-b-PDMAEMA10 has the lowest critical micelle concentration (CMC) value (0.0041 mg mL-1), the highest loading capacity (13.86%) and entrapment efficiency (97.03%). A slow sustained drug release at pH 7.4 with 12.36% in 108 h, while a fast release (42.36%) was observed at pH 5.0. Furthermore, a dissipative particle dynamics (DPD) simulation method was employed to investigate the self-assembly process and pH-responsive behavior of PMs. The optimal drug-carrier ratio (2%) and fraction of water (92%) were confirmed by analyzing the drug distribution and morphology of micelles during the self-assembly process of the block copolymer. The simulation results were consistent with experimental results, indicating DPD simulation shows potential to study the structure properties of reversible cross-linked micelles. The present findings provide a new method for the development of SDDS with good structural stability and controlled drug release properties.

INFLUENCE OF THE PHASE TRANSFER CATALYST ON THE ACCUMULATION AND DECOMPOSITION OF ETHYLBENZENEHYDROPEROXIDE

The regularities of ethylbenzene oxidation and hydroperoxide decomposition in microheterogeneous systems formed by adding sodium dodecyl sulphate to hydrocarbon media have been studied. A pronounced influence of surfactant nature on the transformation mechanism has been revealed. Anionic micellar surfactants including a linear hydrocarbon fragment catalytically accelerate ROOH decomposition, whereas hydrocarbon soluble non-ionic surfactants and solid oxides practically do not influence the reaction rate. Detailed study of the degradation kinetics in the presence of anionic alkyl sulphates has shown that the accelerating effect of surfactants is connected with their colloidal properties, namely, with the formation of joint aggregates of inverse micelles type, which facilitate the destruction of the peroxide bond. For the first time, a synergistic inhibitory effect of sodium alkyl sulphate mixtures with phenolic antioxidants in the oxidation of various hydrocarbons has been found. During the oxidation of ethylbenzene with minor additives (<1%) of sodium dodecyl sulphate (DDS) a unique case of effective self-inhibition has been determined, the mechanism of which includes two steps. Hydroperoxide, the main source of free radicals, decomposes heterolytically in joint microaggregates with DDS. The decomposition occurs selectively with the formation of acetaldehyde and phenol. Phenol being an acceptor of free radicals inhibits the oxidation of ethyl benzene. The main oxidation product of RH in this system is phenol and acetaldehyde. It should be noted that phenols formation at decomposition of alkylaromatic ROOH is usually connected with strong acids. In the case of DDS decomposition of ROOH seems to be driven by the successful orientation of ROOH molecules in the microaggregates formed by anionic surfactants. But a number of experimental factors, namely the influence of the carbon chain length in sodium alkyl sulphates on the dodecane oxidation rate and inertness of the Na2SO4 dispersion in the hydroperoxide decomposition reactions, make it possible to suggest the catalytic reaction of ROOH. Suggest that the catalytic effect of DDS on hydroperoxide decomposition is connected with its colloidal properties and decomposition occurs in common microaggregates formed by DDS and ROOH. The effective activation energy of ROOH decomposition at concentration of 10 mm is Eef = 66.3 kJ/mol. The oxidation of ethyl benzene is completely inhibited at low additions of DDS (1 mM), and the decomposition rate in an atmosphere of N2 significantly increases. DDS increases the effective decomposition constant of ROOH. This surfactant can be considered as an effective catalyst of ROOH decomposition. For citation: Kashkay A.M. Influence of the phase transfer catalyst on the accumulation and decomposition of ethylbenzenehydroperoxide. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 2. P. 100-106. DOI: 10.6060/ivkkt.20236602.6684.

Application of Different Stimuli-Responsive Polymeric Micelles for Drug Release

Achieving controlled release of drugs in disease treatment can greatly improve the utilization rate and therapeutic effect of drugs. Therefore, the development of functional materials with controllable drug release has received more and more attention, such as stimuli-responsive polymeric micelles. The so-called stimuli-responsive polymeric micelles are a new type of polymer micelles that can be used to give responses to different stimulus conditions, such as endogenous stimuli (e.g. light, temperature, ultrasound intensity, magnetic field or electric field) and exogenous stimuli (e.g. redox potential, pH, or enzyme concentration). They can exhibit distinctive size and stability with the variations of the endogenous or exogenous environment. Stimuli-responsive polymeric micelles have several desirable biotechnology applications including their potential use as drug delivery vehicles because tumor tissue and normal tissue is different in physical and chemical properties, where they are very sensitive to endogenous or exogenous environmental changes. This research would mainly discuss different stimuli-responsive polymeric micelles for developing a diverse of drug delivery systems, including light and magnetism response, temperature and ultrasound response, redox response, pH response and enzyme response. Some recent advances and future directions would be briefly referred to as well.

Digital micelles of encoded polymeric amphiphiles for direct sequence reading and ex vivo label-free quantification.

Identification and quantification of synthetic polymers in complex biological milieu are crucial for delivery, sensing and scaffolding functions, but conventional techniques based on imaging probe labellings only afford qualitative results. Here we report modular construction of precise sequence-defined amphiphilic polymers that self-assemble into digital micelles with contour lengths strictly regulated by oligourethane sequences. Direct sequence reading is accomplished with matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry, facilitated by high-affinity binding of alkali metal ions with poly(ethylene glycol) dendrons and selective cleavage of benzyl-carbamate linkages. A mixture of four types of digital micelles could be identified, sequence-decoded and quantified by MALDI and MALDI imaging at cellular, organ and tissue slice levels upon in vivo administration, enabling direct comparison of biological properties for each type of digital micelle in the same animal. The concept of digital micelles and encoded amphiphiles capable of direct sequencing and high-throughput label-free quantification could be exploited for next-generation precision nanomedicine designs (such as digital lipids) and protein corona studies.

Synthesis and Evaluation of a Paclitaxel-Binding Tripeptide Micelle for Lung Cancer Therapy.

A C10CO-NalLeuVal (C10NLV) tripeptide was synthesized and explored as a carrier for paclitaxel (TAX) delivery. Five types of TAX-loaded micelles were produced by loading TAX with different doses of C10NLV. 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay showed that TAX-loaded micelles dramatically reduced TAX IC50 values of TAX-resistant A549 (A549/TAX) and Lewis lung carcinoma (LLC) cells in a C10NLV-dose-dependent manner, with micelles 4 and 5 exhibited comparable inhibitory effects on A549/TAX proliferation. Flow cytometry analysis showed that TAX-loaded micelles 4 promoted lung cancer cell apoptosis in a TAX-dose-dependent manner. Immunofluorescent staining and Western blotting revealed that TAX-loaded micelles 4 dramatically reduced the protein levels of F-actin, p53, Bcl-2, and LC3A/B in A549/TAX cells. Wound healing, cell adhesion, migration, and invasion assays demonstrated that TAX-loaded micelles 4 suppressed the metastatic abilities of lung cancer cells. Furthermore, compared with the same dose of free TAX, TAX-loaded micelles 4 significantly reduced the volumes and weights of A549/TAX-generated tumors as well as the numbers of LLC-generated pulmonary metastatic foci in mice, without affecting the organ/body weight ratios, body weights, and blood cell counts. Histological analysis demonstrated that TAX-loaded micelles 4 administration resulted in tubulin and CD206 downregulation as well as cytoplasm disappearance and nuclear shrinkage in xenograft tumors. These data suggest that TAX-loaded micelles 4 inhibits the proliferative and metastatic capacity of lung cancer cells, despite TAX resistance. TAX-loaded micelles 4 suppresses lung tumor growth and metastasis in vivo without inducing systemic toxicity. Thus, the C10NLV-based TAX delivery is effective and safe to combat TAX resistance and metastasis in lung cancer.

Amphiphilic Diblock Copolymers Bearing Poly(Ethylene Glycol) Block: Hydrodynamic Properties in Organic Solvents and Water Micellar Dispersions, Effect of Hydrophobic Block Chemistry on Dispersion Stability and Cytotoxicity.

Despite the fact that amphiphilic block copolymers have been studied in detail by various methods both in common solvents and aqueous dispersions, their hydrodynamic description is still incomplete. In this paper, we present a detailed hydrodynamic study of six commercial diblock copolymers featuring the same hydrophilic block (poly(ethylene glycol), PEG; degree of polymerization is ca. 110 ± 25) and the following hydrophobic blocks: polystyrene, PS35-b-PEG115; poly(methyl methacrylate), PMMA55-b-PEG95; poly(1,4-butadyene), PBd90-b-PEG130; polyethylene PE40-b-PEG85; poly(dimethylsiloxane), PDMS15-b-PEG115; and poly(ɛ-caprolactone), PCL45-b-PEG115. The hydrodynamic properties of block copolymers are investigated in both an organic solvent (tetrahydrofuran) and in water micellar dispersions by the combination of static/dynamic light scattering, viscometry, and analytical ultracentrifugation. All the micellar dispersions demonstrate bimodal particle distributions: small compact (hydrodynamic redii, Rh ≤ 17 nm) spherical particles ascribed to “conventional” core–shell polymer micelles and larger particles ascribed to micellar clusters. Hydrodynamic invariants are (2.4 ± 0.4) × 10−10 g cm2 s−2 K−1 mol−1/3 for all types of micelles used in the study. For aqueous micellar dispersions, in view of their potential biomedical applications, their critical micelle concentration values and cytotoxicities are also reported. The investigated micelles are stable towards precipitation, possess low critical micelle concentration values (with the exception of PDMS15-b-PEG115), and demonstrate low toxicity towards Chinese Hamster Ovarian (CHO-K1) cells.

Comparative interaction of an anionic dye, ponceau 4R with triple viz., anionic, non-ionic and cationic micellar systems: Spectral and conductometric analysis

In this work, the interaction of ponceau 4R dye (P4R) with triple viz., anionic, nonionic and cationic micellar systems has been studied. The three surfactants employed were nonionic pluronic L-64 (PL-64), anionic sodium dodecyl sulphate (SDS) and cationic cetyl trimethyl ammonium bromide (CTAB). All the three dye - surfactants systems were investigated through UV - visible spectroscopy, conductivity, FT-IR, pH effect and SEM studies. There was short and strong bonding between the dye and all the three types of micelles as observed from FT-IR studies. The conductivity studies displayed greater interaction with CTAB than with SDS. The free energy of micellization, ∆G was observed to be -16.07 kJ mol−1 for P4R+ CTAB and -13.83 kJ mol−1 for P4R + SDS, demonstrating greater spontaneity and stability of the former combination. This can be explained due to strong electrostatic attraction between negatively charged P4R dye and positively charged micelle of CTAB. Overall, the anionic ponceau 4R dye has been successfully incorporated into the nonionic, anionic and cationic micellar systems. This is probably the first report of interaction of a similarly charged dye and surfactant system.

Topological Dynamics of Micelles Formed by Geometrically Varied Surfactants

The molecular architecture of sugar-based surfactants strongly affects their self-assembled structure, i.e., the type of micelles they form, which in turn controls both the dynamics and rheological properties of the system. Here, we report the segmental and mesoscopic structure and dynamics of a series of C16 maltosides with differences in the anomeric configuration and degree of tail unsaturation. Neutron spin-echo measurements showed that the segmental dynamics can be modeled as a one-dimensional array of segments where the dynamics increase with inefficient monomer packing. The network dynamics as characterized by dynamic light scattering show different relaxation modes that can be associated with the micelle structure. Hindered dynamics are observed for arrested networks of worm-like micelles, connected to their shear-thinning rheology, while nonentangled diffusing rods relate to Newtonian rheological behavior. While the design of novel surfactants with controlled properties poses a challenge for synthetic chemistry, we demonstrate how simple variations in the monomer structure can significantly influence the behavior of surfactants.

From Lipids to Micelles- A Tentative Analysis of Drug Delivery

Polymer micelles (PM) are core-shell nanostructures formed by the self-assembly of amphiphilic block copolymers. Due to its hollow form and biocompatibility, it is an excellent drug carrier and has a wide range of uses in the pharmaceutical field. This review summarizes the latest developments in PM development and its applications. First, I explained the basic structure and several types of micelles. This process introduces experiments and parameters to control the shape of the vesicles used for drug delivery. Next, we talked about various common synthetic methods such as the solvent conversion method and the solvent-free method. In addition, we introduce polymer micelles into conventional pharmacies and the difficulties of modern medicine. Finally, it summarizes the morphology, synthesis method and application of PM in the medical field, and provides insights into the future development of vesicle degradation and the biocompatibility of PM preparation and the resulting morphology. In addition to the above, this article also introduces different methods of PM targeting, imaging, and triggered release in pharmaceutical applications.

How multiple noncovalent interactions regulate the aggregation behavior of amphiphilic triblock copolymer/surface-active ionic liquid mixtures

Amphiphilic block copolymers/ionic liquids mixtures have been emerging as a new class of ‘chemical entity’ with numerous advanced applications. However, interaction mechanism governing the aggregation and the microstructure of aggregates are still far from full understanding. Herein, the role of noncovalent interactions in regulation of aggregation behaviors of mixtures of Pluronic F127 and surface-active ionic liquids, i.e. CnmimBr, CnPyBr and CnMPB is investigated by DLS, cryo-TEM, NMR and molecular dynamics simulation. The interaction modes between F127 and SAILs are remarkably dependent on the concentration and cationic headgroup of SAIL. At low SAIL concentration (<CMC), mixed micelles mainly composed of F127 with some SAIL cations embedded into micelles are formed, which was primarily driven by hydrophobic interaction. However, the residence of CnmimBr cations in micelles is quite different from that of CnPyBr and CnMPB cations due to its distinctive hydrogen bonding with PEO segment of F127. Upon further addition of SAILs (CSAILs > CMC), gradual disintegration of F127-rich micelles was observed due to the enhanced repulsive electrostatic force at micellar core-corona interface, accompanying with the re-formation of two types of micelles: one consisting of pure SAILs and one that SAIL micelles bound with F127 monomers via hydrogen bonding and/or hydrophobic interactions. This work provides new insight into the aggregation mechanism of these complex systems and will be helpful to rational tailoring innovative copolymers /IL-based system for specific applications.

Intracellular K+-Responsive Block Copolymer Micelles for Targeted Drug Delivery of Curcumin.

Curcumin (CUR) is a natural bioactive compound that has attracted attention as a “golden molecule” due to its therapeutic properties against several types of tumors. Nonetheless, the antitumor application of CUR is hampered due to its extremely low aqueous solubility and chemical instability. Herein, a novel type of CUR-loaded polymeric micelles with intracellular K+-responsive controlled-release properties is designed and developed. The polymeric micelles are self-assembled by poly (N-isopropylacrylamide-co-acryloylamidobenzo-15-crown-5-co-N, N-dimethylacrylamide)-b-DSPE (PNDB-b-DSPE) block copolymers, and CUR. CUR is successfully loaded into the micelles with a CUR loading content of 6.26 wt%. The proposed CUR-PNDB-DSPE polymeric micelles exhibit a significant CUR release in simulated intracellular fluid due to the formation of 2 : 1 ‘‘sandwich’’ host–guest complexes of 15-crown-5 and K+, which lead to the hydrophilic outer shell of micelles to collapse and the drug to rapidly migrate out of the micelles. In vitro, the B16F10 cell experiment indicates that CUR-PNDB-DSPE micelles exhibit a high cellular uptake and excellent intracellular drug release in response to the intracellular K+ concentration. Moreover, CUR-PNDB-DSPE micelles show high cytotoxicity to B16F10 cells compared to free CUR and CUR-PEG-DSPE micelles. The polymeric micelles with intracellular K+-responsive controlled release properties proposed in this study provide a new strategy for designing novel targeted drug delivery systems for CUR delivery for cancer treatment.