Amphiphilic Diblock Copolymers Research Articles

High Vertical Hole Mobility through Minimization of Water-Induced Traps by F4TCNQ Doping in Conjugated Amphiphilic Diblock Copolymers

High Vertical Hole Mobility through Minimization of Water-Induced Traps by F4TCNQ Doping in Conjugated Amphiphilic Diblock Copolymers

Block and Statistical Copolymers of Methacrylate Monomers with Dimethylamino and Diisopropylamino Groups on the Side Chains: Synthesis, Chemical Modification and Self-Assembly in Aqueous Media.

The synthesis of amphiphilic diblock and statistical (random) copolymers of poly(dimethylamino ethyl methacrylate) and poly((2-(diisopropylamino) ethyl methacrylate) using the reversible addition-fragmentation chain transfer polymerization technique (RAFT polymerization) is reported. The precursor copolymers were chemically modified to create derivative copolymers of polyelectrolyte and polyampholyte nature with novel solution properties. Moreover, their molecular and physicochemical characteristics, as well as their self-assembly in aqueous media as a function of molecular architecture and composition, are investigated by using size exclusion chromatography, spectroscopic characterization techniques and light scattering techniques. Furthermore, the behavior and properties of the obtained micelles and aggregates were studied, depending on the pH, temperature and ionic strength of the aqueous solutions. The response of the systems to changes in these parameters shows interesting behavior and new properties that are useful for their utilization as nanocarriers of pharmaceutical compounds.

Easy Synthetic Access to High‐Melting Sulfurated Copolymers and their Self‐Assembling Diblock Copolymers from Phenylisothiocyanate and Oxetane

AbstractAlthough sulfurated polymers promise unique properties, their controlled synthesis, particularly when it comes to complex and functional architectures, remains challenging. Here, we show that the copolymerization of oxetane and phenyl isothiocyanate selectively yields polythioimidocarbonates as a new class of sulfur containing polymers, with narrow molecular weight distributions (Mn=5–80 kg/mol with Đ≤1.2; Mn,max=124 kg/mol) and high melting points of up to 181 °C. The method tolerates different substituent patterns on both the oxetane and the isothiocyanate. Self‐nucleation experiments reveal that π‐stacking of phenyl substituents, the presence of unsubstituted polymer backbones, and the kinetically controlled linkage selectivity are key factors in maximising melting points. The increased tolerance to macro‐chain transfer agents and the controlled propagation allows the synthesis of double crystalline and amphiphilic diblock copolymers, which can be assembled into micellar‐ and worm‐like structures with amorphous cores in water. In contrast, crystallization driven self‐assembly in ethanol gives cylindrical micelles or platelets.

Easy Synthetic Access to High-Melting Sulfurated Copolymers and their Self-Assembling Diblock Copolymers from Phenylisothiocyanate and Oxetane.

Although sulfurated polymers promise unique properties, their controlled synthesis, particularly when it comes to complex and functional architectures, remains challenging. Here, we show that the copolymerization of oxetane and phenyl isothiocyanate selectively yields polythioimidocarbonates as a new class of sulfur containing polymers, with narrow molecular weight distributions (Mn=5-80 kg/mol with Đ≤1.2; Mn,max=124 kg/mol) and high melting points of up to 181 °C. The method tolerates different substituent patterns on both the oxetane and the isothiocyanate. Self-nucleation experiments reveal that π-stacking of phenyl substituents, the presence of unsubstituted polymer backbones, and the kinetically controlled linkage selectivity are key factors in maximising melting points. The increased tolerance to macro-chain transfer agents and the controlled propagation allows the synthesis of double crystalline and amphiphilic diblock copolymers, which can be assembled into micellar- and worm-like structures with amorphous cores in water. In contrast, crystallization driven self-assembly in ethanol gives cylindrical micelles or platelets.

Flow-driven translocation of polymer vesicle through a nanochannel

Flow-driven translocation of a polymer vesicle self-assembled from amphiphilic diblock copolymers through a nanochannel is studied using hybrid Lattice-Boltzmann Molecular Dynamics simulations. Three translocation modes are discovered: a single vesicle, small vesicles, and tiny micelles in sequence, respectively, as the width of the nanochannel is decreased, which is confirmed by the self-consistent field theory calculations. Accordingly, spherical vesicles, ellipsoidal vesicles, and worm-like micelles are formed sequentially after crossing the nanochannel. More importantly, we find that the critical flow rate monotonically decreases as the ratio of the polymer vesicle size and the width of the nanochannel decreases until it approaches 1. Our results provide a basis for characterizing the stability of vesicles or sorting vesicles with different sizes and also point to a new idea of regulating spherical vesicles to ellipsoidal vesicles or worm-like micelles.

Thermosensitive polymer prodrug nanoparticles prepared by an all-aqueous nanoprecipitation process and application to combination therapy

Despite their great versatility and ease of functionalization, most polymer-based nanocarriers intended for use in drug delivery often face serious limitations that can prevent their clinical translation, such as uncontrolled drug release and off-target toxicity, which mainly originate from the burst release phenomenon. In addition, residual solvents from the formulation process can induce toxicity, alter the physico-chemical and biological properties and can strongly impair further pharmaceutical development. To address these issues, we report polymer prodrug nanoparticles, which are prepared without organic solvents via an all-aqueous formulation process, and provide sustained drug release. This was achieved by the “drug-initiated” synthesis of well-defined copolymer prodrugs exhibiting a lower critical solution temperature (LCST) and based on the anticancer drug gemcitabine (Gem). After screening for different structural parameters, prodrugs based on amphiphilic diblock copolymers were formulated into stable nanoparticles by all-aqueous nanoprecipitation, with rather narrow particle size distribution and average diameters in the 50–80 nm range. They exhibited sustained Gem release in human serum and acetate buffer, rapid cellular uptake and significant cytotoxicity on A549 and Mia PaCa-2 cancer cells. We also demonstrated the versatility of this approach by formulating Gem-based polymer prodrug nanoparticles loaded with doxorubicin (Dox) for combination therapy. The dual-drug nanoparticles exhibited sustained release of Gem in human serum and acidic release of Dox under accelerated pathophysiological conditions. Importantly, they also induced a synergistic effect on triple-negative breast cancer line MDA-MB-231, which is a relevant cell line to this combination.

Abstract 3207: Chemical fabrication and characterization of a novel nanoparticle of the histone deacetylase (HDACi) romidepsin

Abstract Introduction: Histone Deacetylase inhibitors (HDACi) are important drugs for the treatment of patients with PTCL (peripheral T-cell lymphoma). Romidepsin (R), a potent Class I HDACi, is given intravenously, weekly for three to four consecutive weeks. R has a half-life of three hours and is extensively protein bound. The indication for R in PTCL was recently withdrawn due to a failed Phase 4 study. Given the need for new drugs in PTCL, and the importance of epigenetically targeted drugs for the disease, we developed a first-in-class nanoparticle of R (NR) deploying a proprietary nanochemistry platform. Methods: We modified the bulk nanoprecipitation method with FDA approved and Generally Recognized as Safe (GRAS) materials, specifically including PEGylated amphiphilic diblock copolymers, to develop NR combinatorially. By combining a drug and polymer solution with an anti-solvent, we produced core-shell structured NR particles with “stealth” properties. To achieve high R loading, stability, purity, scalability, and reproducibility, we devised a multi-pronged optimization system by modulating parameter sets in tandem. We determined the optimal parameters for the "lockdown" formulation. We purified NR by using centrifugal filters and determined stability by storing at 4°C. We used Cryo-electron microscopy (cryo-EM), Dynamic Light Scattering (DLS), and Liquid Chromatography-Mass Spectrometry (LC-MS) to determine the morphology, size, PDI, and drug concentration of NR. We developed fluorescent-NR with DiO dye to test bioavailability. We tested NR in T-cell lymphoma cell lines for histone acetylation and apoptosis induction. Furthermore, we investigated the in vivo pharmacokinetics and toxicity of NR in PTCL xenograft mouse model and quantified the drug by LC-MS. Results: The physiochemical analysis of NR demonstrated that the particles were spherical, with a hydrodynamic diameter of 46 ±5 nm and PDI of 0.15 - 0.2. NR had a negative zeta potential and an exceptional drug encapsulation efficiency of over 50% (>500 µg/mL). NR exhibited high stability with respect to size, PDI and drug concentration for over two years. Flow cytometry and western blot analyses indicate NR induces apoptosis and histone acetylation in a time and dose-dependent manner, equivalent to or better than that observed for R. NR’s AUC increased 25-fold when administered intravenously. NR had superior tolerability, and DiO-NR confirmed superior biodistribution in tumor in a PTCL xenograft mouse model. Conclusion: We developed a cutting-edge approach with minimum excipients, which enabled NR scale up with batch-to-batch reproducibility and high quality co-packaging of fluorescent dye and drug. NR improved R’s pharmacokinetic profile and efficacy in pre-clinical xenograft mice models. Our versatile technology enables Chemistry Materials and Controls products, an essential step in clinical product development. Citation Format: Samir Zuberi, Deepthi P. Damera, Ipsita Pal, Susan Walker, Ramesh Katla, Colin Haws, Akhil Gajjala, Andrea Joyner, Kallesh D. Jayappa, David J. Feith, Todd E. Fox, Thomas P. Loughran, Owen A. O'Connor, Anuradha Illendula. Chemical fabrication and characterization of a novel nanoparticle of the histone deacetylase (HDACi) romidepsin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3207.

Ordered mesoporous nanofibers mimicking vascular bundles for lithium metal batteries.

Hierarchical self-assembly with long-range order above centimeters widely exists in nature. Mimicking similar structures to promote reaction kinetics of electrochemical energy devices is of immense interest, yet remains challenging. Here, we report a bottom-up self-assembly approach to constructing ordered mesoporous nanofibers with a structure resembling vascular bundles via electrospinning. The synthesis involves self-assembling polystyrene (PS) homopolymer, amphiphilic diblock copolymer, and precursors into supramolecular micelles. Elongational dynamics of viscoelastic micelle solution together with fast solvent evaporation during electrospinning cause simultaneous close packing and uniaxial stretching of micelles, consequently producing polymer nanofibers consisting of oriented micelles. The method is versatile for the fabrication of large-scale ordered mesoporous nanofibers with adjustable pore diameter and various compositions such as carbon, SiO2, TiO2 and WO3. The aligned longitudinal mesopores connected side-by-side by tiny pores offer highly exposed active sites and expedite electron/ion transport. The assembled electrodes deliver outstanding performance for lithium metal batteries.

Diblock Copolymers of Methacryloyloxyethyl Phosphorylcholine and Dopamine Methacrylamide: Synthesis and Real-Time Adsorption Dynamics by SEIRAS and RAIRS.

Amphiphilic diblock copolymers containing a block of 2-methacryloyloxyethyl phosphorylcholine (MPC) with unique properties to prevent nonspecific protein adsorption and enhance lubrication in aqueous media and a block of dopamine methacrylamide (DOPMA) distinguished by excellent adhesion performance were synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization for the first time. The DOPMA monomer with an acetonide-protected catechol group (acetonide-protected dopamine methacrylamide (ADOPMA)) was used, allowing the prevention of undesirable side reactions during polymerization and oxidation during storage. The adsorption behavior of the diblock copolymers with protected and unprotected catechol groups on gold surfaces was probed using attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy, surface-enhanced infrared absorption spectroscopy (SEIRAS), and reflection-absorption infrared spectroscopy (RAIRS). The copolymers pMPC-b-pADOPMA demonstrated physisorption with rapid adsorption and ultrasound-assisted desorption, while the copolymers pMPC-b-DOPMA exhibited chemical adsorption with slower dynamics but a stronger interaction with the gold surface. SEIRAS and RAIRS allowed proving the reorientation of the diblock copolymers during adsorption, demonstrating the exposure of the pMPC block toward the aqueous phase.

Effect of aromatic substituents on thermoresponsive functional polycaprolactone micellar carriers for doxorubicin delivery.

Amphiphilic functional polycaprolactone (PCL) diblock copolymers are excellent candidates for micellar drug delivery. The functional groups on the backbone significantly affect the properties of PCL. A systematic investigation of the effect of aromatic substituents on the self-assembly of γ-functionalized PCLs and the delivery of doxorubicin (DOX) is presented in this work. Three thermoresponsive amphiphilic diblock copolymers with poly(γ-benzyloxy-ε-caprolactone) (PBnCL), poly(γ-phenyl- ε-caprolactone) (PPhCL), poly(γ-(4-ethoxyphenyl)-ε-caprolactone) (PEtOPhCL), respectively, as hydrophobic block and γ-tri(ethylene glycol) functionalized PCL (PME3CL) as hydrophilic block were prepared through ring-opening polymerization (ROP). The thermoresponsivity, thermodynamic stability, micelle size, morphology, DOX-loading, and release profile were determined. The LCST values of amphiphilic diblock copolymers PME3CL-b-PBnCL, PME3CL-b-PPhCL, and PME3CL-b-PEtOPhCL are 74.2°C, 43.3°C, and 37.3°C, respectively. All three copolymers formed spherical micelles in phosphate-buffered saline (PBS, 1×, pH = 7.4) at low concentrations ranging from 8.7 × 10-4g/L to 8.9 × 10-4g/L. PME3CL-b-PBnCL micelles showed the highest DOX loading capacity of 3.01 ± 0.18 (wt%) and the lowest drug release, while PME3CL-b-PEtOPhCL micelles exhibited the lowest DOX loading capacity of 1.95 ± 0.05 (wt%) and the highest drug release. Cytotoxicity and cellular uptake of all three micelles were assessed in vitro using MDA-MB-231 breast cancer cells. All three empty micelles did not show significant toxicity to the cells at concentrations high up to 0.5mg/mL. All three DOX-loaded micelles were uptaken into the cells, and DOX was internalized into the nucleus of the cells.

Controlling the function of bioactive worm micelles by enzyme-cleavable non-covalent inter-assembly cross-linking

Drugs that form self-assembled supramolecular structures to be most-active is a promising way of creating new highly specific and active pharmaceuticals. Controlling the activity of bioactive supramolecular structures such as drug-loaded micelles is possible by both core/shell and inter-assembly cross-linking. However, if the flexibility of the assembly is mandatory for the activity cross-linking is not feasible. Thus, such structures cannot be manipulated in their activity.The present study demonstrates a novel concept to control the activity of not drug-releasing, non-cross-linked bioactive superstructures. This is achieved by formation of nanostructured nanoparticles derived by non-covalent inter-assembly cross-linking of the superstructures. This is shown on the example of amphiphilic diblock-copolymers conjugated with the antibiotic ciprofloxacin (CIP). These polymer-antibiotic conjugates form worm micelles, which greatly activate the conjugated antibiotic without releasing it. Non-covalent inter-assembly cross-linking of these CIP-worm-micelles with amphiphilic triblock copolymers terminated with lipase-cleavable esters leads to nanostructured nanoparticles that resemble cross-linked worm micelles and show an up to 135-fold lower activity than the free worm micelles. The activity of the worm-micelles can be fully recovered by cleaving the end groups of the polymeric cross-linker with lipase.

A novel ion-selective POSS-based pore from amphiphilic diblock copolymers

Biological ion-selective channels possess an unparalleled combination of high ion conductance and selectivity. Pores with comparable characteristics are highly required in industrial applications, e.g., for ion separation from brines. Yet, bio-channels' application is limited due to their instability, complexity in production, and low surface density. Artificial channels with a satisfactory trade-off between selectivity and conductance may represent an alternative. We propose taking advantage of the amphiphilic properties and high chemical variability of polyhedral oligomeric silsesquioxane (POSS), thus far used as a filler in nano-composite membranes. We designed and synthesized diblock copolymers where the hydrophobic block contained POSS cages decorated with isobutyl groups. Polymers containing four (SP5B3-5) or eight (Au22) POSS cages appeared capable of self-assembling into alkali ion-selective pores in planar lipid bilayers. Based on polymer structure and dose effect experiments, we propose that SP5B3-5 forms a tetrameric pore, with two monomers from each membrane leaflet, and Au22 forms an antiparallel dimeric pore. Both polymers prefer cations over anions. The unitary conductance decreases in the order Cs+ > K+ > Na+ of the Eisenman sequence I, indicating that the selectivity primarily stems from the penalty for ion dehydration. The permeabilities for Cs+, K+ and Na+ relate as 2.5 : 1.9 : 1 for SP5B3-5, and as 2.5 : 1.5 : 1 for Au22. The observation is compatible with a conductivity pathway where six oxygen atoms of the surrounding four POSS cages coordinate an ion within the pore. The artificial POSS-based pores pave the way for producing ion-selective membranes with high throughput.

The Effect of Colloidal Nanoparticles on Phase Separation of Block and Heteroarm Star Copolymers Confined between Polymer Brushes.

The effect of colloidal nanoparticles on the phase changes of the amphiphilic AB linear diblock, A1A2B, and A2B heteroarm star copolymers confined between two polymer brush substrates was investigated by using a real-space self-consistent field theory. By changing the concentrations of nanoparticles and polymer brushes, the phase structure of the amphiphilic AB copolymer transforms from lamellar to core-shell hexagonal phase to cylinder phase. The pattern of A2B heteroarm star copolymer changes from core-shell hexagonal phases to lamellar phases and the layer decreases when increasing the density of the polymer brushes. The results showed that the phase behavior of the system is strongly influenced by the polymer brush architecture and the colloidal nanoparticle numbers. The colloidal nanoparticles and the soft confined surface of polymer brushes make amphiphilic AB copolymers easier to form ordered structures. The dispersion of the nanoparticles was also investigated in detail. The soft surfaces of polymer brushes and the conformation of the block copolymers work together to force the nanoparticles to disperse evenly. It will give helpful guidance for making some new functional materials by nano etching technology, nano photoresist, and nanoprinting.

Energetic and Entropic Motifs in Vesicle Morphogenesis in Amphiphilic Diblock Copolymer Solutions

Coarse-grained molecular dynamic simulations are employed to investigate the spatiotemporal evolution of vesicles (polymersomes) via self-assembly of randomly distributed amphiphilic diblock copolymers PB-PEO (Poly(Butadiene)-b-Poly(Ethylene Oxide)) in water. The vesiculation pathway consists of several intermediate structures, such as spherical/rodlike aggregates, wormlike micelles, lamellae, and cavities. The lamella-to-vesicle transition occurs at a constant aggregation number and is accompanied by a reduction in the solvent-accessible surface area. Simulation predictions are in qualitative agreement with the mechanism of vesicle formation in which the unfavorable hydrophobic interactions between water molecules and polymer segments, along the edge of the lamella, are eliminated at the expense of gaining curvature energy. However, rod–lamella–vesicle transition is accompanied by an increase in copolymer packing density. Hence, the change in the surface area accompanying vesiculation predicted by the simulations is significantly lower than theoretical estimates. Changes in information entropy, quantified by the expectation of the logarithm of the probability distribution function of the segmental stretch parameter s, defined as the difference between the maximum and instantaneous segmental extension, are statistically insignificant along the vesiculation pathway. For rods, lamellae, and polymersomes, s follows a log normal distribution. This is explained based on the configurational dynamics of a single diblock chain in water.

Self-assembly of temperature-responsive di-block polypeptides functionalized with unnatural amino acids.

The incorporation of unnatural amino acids (uAAs) into protein-based polymers has emerged as a powerful methodology to expand their chemical repertoire. Recently, we demonstrated that incorporating uAAs into two temperature-responsive protein-based polymers-namely resilin- and elastin-like polypeptides (RLPs and ELPs, respectively)-can alter their properties. In this study, we incorporated aromatic uAAs into the protein sequence of RLP-ELP diblocks to yield new and diverse assemblies from a single DNA template. Specifically, we show that incorporating aromatic uAAs can modulate the phase-transition behaviors and self-assembly of the diblocks into various morphologies, including spherical and cylindrical micelles and single- and double-layered vesicles, with some constructs also demonstrating a temperature-responsive shape-shifting behavior. Next, we evaluated the ability of the RLP-ELP assemblies to encapsulate a chemotherapeutic drug, doxorubicin, and show how the identity of the incorporated uAAs and the morphology of the nanostructure affect the encapsulation efficiency. Taken together, our findings demonstrate that the multi-site incorporation of uAAs into temperature-responsive, amphiphilic protein-based diblock copolymers is a promising approach for the functionalization and tuning of self-assembled nanostructures.

Synthesis of Amphiphilic Block Copolymer and Its Application in Pigment-Based Ink.

Amphiphilic block copolymers-based aqueous color inks show great potential in the field of visual communication design. However, the conventional step-by-step chemistry employed to synthesize the amphiphilic block copolymers is intricate, with low yield and high economic and environmental costs. In this work, we present a novel method for preparing an amphiphilic AB di-block copolymer of PCL-b-PAA by employing a combined polymerization strategy that involves both cationic ring-opening polymerization (ROP) of the ε-caprolactone monomer and the reversible addition-fragmentation chain-transfer (RAFT) polymerization on the acrylic acid monomer simultaneously. The corresponding polycaprolactone (PCL) and polyacrylic acid (PAA) serve as the hydrophobic and hydrophilic units, respectively. The effectiveness of the amphiphilic AB di-block copolymer as the polymeric pigment dispersant for water-based color inks is evaluated. The amphiphilic AB di-block copolymer of PCL-b-PAA exhibits a molecular weight of 1400 g mol-1, which is consistent with the theoretical value and suitable for polymeric dispersant application. The high surface excess (Γmax) of the PCL-b-PAA in water indicates a densely packed molecular morphology at the water/air interface. Additionally, micelles can be stably formed in the aqueous PCL-b-PAA solution at very low concentrations by demonstrating a low CMC value of 10-4 wt% and a micelle dimension of approximately 30 nm. The model ink dispersion is prepared using organic dyes (Disperse Yellow 232) and the amphiphilic block copolymer of PCL-b-PAA. The dispersion demonstrates near-Newtonian behavior, which is highly favorable for the application as inkjet ink. Furthermore, the ink dispersion displays a low viscosity, making it particularly suitable for visual communication design and printing purposes. Moreover, the ink dispersion demonstrates an unimodal distribution of the particle size, with an average diameter of approximately 500 nm. It retains exceptional stability of dispersion and even conducts a thermal aging treatment at 60 °C for 5 days. This work presents a facile and efficient synthetic strategy and molecular design of AB di-block copolymer-based dispersants for dye dispersions.

Dual-templating synthesis of superhydrophobic Fe3O4/PSt porous composites for highly efficient oil-water separation

Fe3O4/PSt porous composites with low density, interconnected network structure and superhydrophobic were prepared successfully by a dual-templating method, including High Internal Phase Emulsion (HIPEs) template method and the introduction of organic template species. It was worth mentioning that a novel amphiphilic di-block copolymers P(DMAEMA-b-St) were prepared as emulsifier by reversible addition fragmentation chain transfer (RAFT) polymerization method. At the same time, the effects of PS block length, emulsifier content, Fe3O4 content, DVB content and dispersed phase proportion on HIPEs droplet size and the corresponding polyHIPEs oil absorption were researched. The results showed that the oil adsorption capacity of 9.43 g/g toward toluene under optimal conditions. Subsequently, adsorption isotherm and adsorption kinetics were investigated. The results were shown that the adsorption of oil on adsorbent followed Freundlich model and pseudo-second-order (PSO) model. In addition, the adsorption experiments on a variety of oils demonstrated the wide applicability of Fe3O4/PSt porous composites. The cycling experiments proved that the Fe3O4/PSt porous composites had excellent cycling ability, were easy to recover and could be reused for multiple times. Finally, the adsorption column experiments showed that Fe3O4/PSt porous composites had powerful potential for industrial applications.

H2O2-Responsive Polymeric Micelles of Biodegradable Aliphatic Poly(carbonate)s as Promising Therapeutic Agents for Inflammatory Diseases.

Excessive amounts of reactive oxygen species (ROS) cause various biological damages and are involved in many diseases, such as cancer, inflammatory and thrombotic complications, and neurodegenerative diseases. Thus, ROS-responsive polymers with inherent ROS scavenging activity and biodegradability are extremely needed for the efficient treatment of ROS-related diseases. Here, this work fabricates the amphiphilic diblock copolymer PEG-b-PBC via ring-opening polymerization (ROP) of phenylboronic acid ester conjugated cyclic carbonate monomer. The copolymer easily forms micelles (BCM) and scavenges ROS rapidly. BCM not only releases the delivered drug but degrades to produce the small molecules p-hydroxybenzyl alcohol (HBA) with anti-inflammatory capability in the presence of H2O2. BCM can reduce the oxidative stress of human umbilical vein endothelial cells (HUVEC) and the levels of inflammatory factors secreted by macrophages, showing antioxidative and anti-inflammatory activity. Finally, BCM exerts a significant capability to reduce the complications of inflammation and thrombosis in vivo. The biodegradable aliphatic poly(carbonate)s have the potential to be used for drug delivery systems (DDS) for diseases induced by reactive oxygen species.

Tunable Hairy and Crew‐Cut Supermicelles from Poly(N‐octyl glycine)‐Based Diblock Copolymer via a Hierarchical Assembly Strategy

AbstractFabrication of hierarchical superstructures by utilizing bioinspired polymeric materials shows great potential that has attracted considerable attention. A new hierarchical assembly approach has been developed to fabricate supramolecular structures in a one‐pot preparation from crystallizable polypeptoids‐based block copolymers. Herein, both hairy and crew‐cut supermicelles are reported by systematically tuning the temperature and solvent from a series of poly(ethylene glycol)112‐block‐poly(N‐octylglycine)n (PEG112‐b‐PNOGn) with different degrees of polymerization of PNOG. The incorporation of a third polar component poly(N‐allylglycine)‐graft‐COOH (PNAG‐g‐COOH) into the amphiphilic diblock copolymers can promote the formation of crew‐cut supermicelles owing to enhanced intermolecular interactions. It is demonstrated that both surface energy and crystallization energy are of great importance for the preparation of different types of supermicelles.

Novel polyvinyl chloride ultrafiltration membranes blended with amphiphilic polyethylene glycol-block-poly(1, 2-dichloroethylene) copolymer for oily wastewater treatment

Amphiphilic di-block copolymer consisting of polyethylene glycol (PEG) and poly(1,2-dichloroethylene) (PDCE) blocks was synthesized following the atom transfer radical polymerization (ATRP) procedure. The chemical structure of the obtained di-block copolymer PEG-b-PDCE was confirmed by different characterization techniques. Polyvinyl chloride (PVC) blend PEG-b-PDCE ultrafiltration (UF) membranes (PVC/PEG-b-PDCE) were prepared using the non-solvent induced phase separation (NIPS) technique and their characteristics were investigated as a function of the PEG-b-PDCE blending ratio in the casting solution. Water contact angle, permeate flux, and oil–water emulsion separation tests were performed to evaluate the hydrophilic character, permeability and anti-fouling membrane performance. It was found that the presence of PEG-b-PDCE copolymer affected the morphological structure of the membrane showing its good pore-forming capability. The oil rejection ability and anti-fouling properties of the blend membranes were improved by increasing the PEG-b-PDCE content up to 0.075 wt%. Compared to PVC membrane, the blend membrane prepared with 0.075 wt% PEG-b-PDCE exhibited about four times higher permeability with an excellent oil rejection factor, 98.78 %, indicating that the PVC/PEG-b-PDCE blend membranes have high potential in oily wastewater treatment.