Design principles, synthesis and biomedical applications of polymer vesicles with inhomogeneous membranes

Architecting Multicompartmentalized, Giant Vesicles with Recombinant Fusion Proteins

We present a straightforward strategy for constructing giant, multicompartmentalized vesicles using recombinant fusion proteins. Our method leverages the self-assembly of globule-zipper-elastin-like polypeptide fusion protein complexes in aqueous conditions, eliminating the need for organic solvents and chemical conjugation. By employing the thin-film rehydration method, we have successfully encapsulated a diverse range of bioactive macromolecules and engineered organelle-like compartments─ranging from soluble proteins and coacervate droplets to vesicles─within these protein-assembled giant vesicles. This approach also facilitates the integration of water-soluble block copolymers, enhancing the structural stability and functional versatility of the vesicles. Our results suggest that these multicompartment giant protein vesicles not only mimic the complex architecture of living cells but also support biochemically distinct reactions regulated by functionally folded proteins, providing a robust model for studying cellular processes and designing microreactor systems. This work highlights the transformative potential of self-assembling recombinant fusion proteins in artificial cell design.

Advances in block copolymer-phospholipid hybrid vesicles: from physical-chemical properties to applications

Hybrid vesicles, made of lipids and amphiphilic block copolymers, have become increasingly popular thanks to their versatile properties that enable the construction of intricate membranes mimicking cellular structures. This tutorial review gives an overview over the different hybrid vesicle designs, and provides a detailed analysis of their properties, including their composition, membrane fluidity, membrane homogeneity, permeability, stability. The review puts emphasis on the application of these hybrid vesicles in bottom-up synthetic biology and aims to offer an overview of design guidelines, particularly focusing on composition, to eventually realize the intended applications of these hybrid vesicles.

Ultrasound-Based Micro-/Nanosystems for Biomedical Applications

Due to the intrinsic non-invasive nature, cost-effectiveness, high safety, and real-time capabilities, besides diagnostic imaging, ultrasound as a typical mechanical wave has been extensively developed as a physical tool for versatile biomedical applications. Especially, the prosperity of nanotechnology and nanomedicine invigorates the landscape of ultrasound-based medicine. The unprecedented surge in research enthusiasm and dedicated efforts have led to a mass of multifunctional micro-/nanosystems being applied in ultrasound biomedicine, facilitating precise diagnosis, effective treatment, and personalized theranostics. The effective deployment of versatile ultrasound-based micro-/nanosystems in biomedical applications is rooted in a profound understanding of the relationship among composition, structure, property, bioactivity, application, and performance. In this comprehensive review, we elaborate on the general principles regarding the design, synthesis, functionalization, and optimization of ultrasound-based micro-/nanosystems for abundant biomedical applications. In particular, recent advancements in ultrasound-based micro-/nanosystems for diagnostic imaging are meticulously summarized. Furthermore, we systematically elucidate state-of-the-art studies concerning recent progress in ultrasound-based micro-/nanosystems for therapeutic applications targeting various pathological abnormalities including cancer, bacterial infection, brain diseases, cardiovascular diseases, and metabolic diseases. Finally, we conclude and provide an outlook on this research field with an in-depth discussion of the challenges faced and future developments for further extensive clinical translation and application.

Robust Electrostatic-Templated Polymerization for Controllable Synthesis of Stable and Permeable Polyelectrolyte Vesicles

Polymer vesicles are of profound interest for designing delivery vehicles and nanoreactors toward a variety of biomedical and catalytic applications, yet robust synthesis of stable and permeable vesicles remains challenging. Here, we propose an electrostatic-templated polymerization that enables fabrication of polyelectrolyte vesicles with simultaneously regulated stability and permeability. In our design, cationic monomers were copolymerized with cross-linkers in the presence of a polyanionic-neutral diblock copolymer as a template. By properly choosing the block length ratio of the template, we fabricated a type of polyion complex vesicle consisting of a cross-linked cationic membrane, electrostatically assembled with the template copolymer which can be removed by sequential dissociation and separation under concentrated salt. We finally obtained stable polyelectrolyte vesicles of regulated size, membrane permeability, and response properties by tuning the synthesis factors including ionic strength, cross-linker type, and fraction as well as different monomers and concentrations. As a proof-of-concept, lipase was loaded in the designed cationic vesicles, which exhibited enhanced enzyme stability and activity. Our study has developed a novel and robust strategy for controllable synthesis of a new class of stable and permeable polymer (polyelectrolyte) vesicles that feature great potential applications as functional delivery carriers and nanoreactors.

Polymersomes in Drug Delivery─From Experiment to Computational Modeling

Polymersomes, composed of amphiphilic block copolymers, are self-assembled vesicles that have gained attention as potential drug delivery systems due to their good biocompatibility, stability, and versatility. Various experimental techniques have been employed to characterize the self-assembly behaviors and properties of polymersomes. However, they have limitations in revealing molecular details and underlying mechanisms. Computational modeling techniques have emerged as powerful tools to complement experimental studies and enabled researchers to examine drug delivery mechanisms at molecular resolution. This review aims to provide a comprehensive overview of the state of the art in the field of polymersome-based drug delivery systems, with an emphasis on insights gained from both experimental and computational studies. Specifically, we focus on polymersome morphologies, self-assembly kinetics, fusion and fission, behaviors in flow, as well as drug encapsulation and release mechanisms. Furthermore, we also identify existing challenges and limitations in this rapidly evolving field and suggest possible directions for future research.

Co-assembly of Amphiphilic Triblock Copolymers with Nanodrugs and Drug Release Kinetics in Solution

Polymeric vesicles present great potential in disease treatment as they can be featured as a structurally stable and easily functionalized drug carrier that can simultaneously encapsulate multiple drugs and release them on-demand. Based on the dissipative particle dynamics (DPD) simulation, the drug-loaded vesicles were designed by the co-assembly process of linear amphiphilic triblock copolymers and hydrophobic nanodrugs in solvents, and most importantly, the drug release behavior of drug-loaded vesicles were intensively investigated. The drug-loaded aggregates, such as vesicles, spherical micelles, and disk-like micelles, were observed by varying the size and concentration of nanodrugs and the length of the hydrophobic block. The distribution of nanodrugs in the vesicles was intensively analyzed. As the size of the nanodrugs increases, the localization of nanodrugs change from being unable to fully wrap in the vesicle wall to the uniform distribution and finally to the aggregation in the vesicles at the fixed concentration of nanodrugs. The membrane thickness of the drug-loaded polymeric vesicle can be increased, and the nanodrugs localized closer to the center of the vesicle by increasing the length of the hydrophobic block. The nanodrugs will be released from vesicles by varying the interactions between the nanodrug and the solvent or the hydrophobic block and the solvent, respectively. We found that the release kinetics conforms to the first-order kinetic model, which can be used to fit the cumulative release rate of nanodrugs over time. The results showed that increasing the size of nanodrugs, the length of hydrophobic block, and the interaction parameters between the hydrophobic block and the solvent will slow down the release rate of the nanodrug and change the drug release process from monophasic to biphasic release model.

Physically and Chemically Compartmentalized Polymersomes for Programmed Delivery and Biological Applications

Multicompartment polymersomes (MCPs) refer to polymersomes that not only contain one single compartment, either in the membrane or in the internal cavity, but also mimic the compartmentalized structure of living cells, attracting much attention in programmed delivery and biological applications. The investigation of MCPs may promote the application of soft nanomaterials in biomedicine. This Review seeks to highlight the recent advances of the design principles, synthetic strategies, and biomedical applications of MCPs. The compartmentalization types including chemical, physical, and hybrid compartmentalization are discussed. Subsequently, the design and controlled synthesis of MCPs by the self-assembly of amphiphilic polymers, double emulsification, coprecipitation, microfluidics and particle assembly, etc. are summarized. Furthermore, the diverse applications of MCPs in programmed delivery of various cargoes and biological applications including cancer therapy, antimicrobials, and regulation of blood glucose levels are highlighted. Finally, future perspectives of MCPs from the aspects of controlled synthesis and applications are proposed.

Polymersome Membrane Engineering with Active Targeting or Controlled Permeability for Responsive Drug Delivery

Polymersomes have been extensively investigated for drug delivery as nanocarriers for two decades due to a series of advantages including high stability under physiological conditions, simultaneous encapsulation of hydrophilic and hydrophobic drugs inside inner cavities and membranes, respectively, and facile adjustment of membrane and surface properties, as well as controlled drug release through incorporation of stimuli-responsive components. Despite these features, polymersome nanocarriers frequently suffer from nontargeting delivery and poor membrane permeability. In recent years, polymersomes have been functionalized for more efficient drug delivery. The surface shells were explored to be modified with diverse active targeting groups to improve disease-targeting delivery. The membrane permeability of the polymersomes was adjusted by incorporation of the stimuli-responsive components for smart controlled transportation of the encapsulated drugs. Therefore, being the polymersome-biointerface, tailorable properties can be introduced by its carefully modulated engineering. This review elaborates on the role of polymersome membranes as a platform to incorporate versatile features. First, we discuss how surface functionalization facilitates the directional journey to the targeting sites toward specific diseases, cells, or intracellular organelles via active targeting. Moreover, recent advances in the past decade related to membrane permeability to control drug release are also summarized. We finally discuss future development to promote polymersomes as in vivo drug delivery nanocarriers.

Membrane and Lumen-Compartmentalized Polymersomes for Biocatalysis and Cell Mimics

Compartmentalization is a crucial feature of a natural cell, manifested in cell membrane and inner lumen. Inspired by the cellular structure, multicompartment polymersomes (MCPs), including membrane-compartmentalized polymersomes and lumen-compartmentalized polymersomes (polymersomes-in-polymersomes), have aroused great expectations for biological applications such as biocatalysis and cell mimics in the past decades. Compared with traditional polymersomes, MCPs have advantages in encapsulating multiple enzymes separately for multistep enzymatic cascade reactions. In this review, first, the design principles and preparation methods of membrane-compartmentalized and lumen-compartmentalized polymersomes are summarized. Next, recent advances of MCPs as nanoreactors and cell mimics to mimic subcellular organelles or artificial cells are discussed. Finally, the future research directions of MCPs are prospected.

Polymeric Bowl-Shaped Nanoparticles: Hollow Structures with a Large Opening on the Surface

Polymeric bowl-shaped nanoparticles (BNPs) are anisotropic hollow structures with large openings on the surface, which have shown advantages such as high specific area and efficient encapsulation, delivery and release of large-sized cargoes on demand compared to solid nanoparticles or closed hollow structures. Several strategies have been developed to prepare BNPs based on either template or template-free methods. For instance, despite the widely used self-assembly strategy, alternative methods including emulsion polymerization, swelling and freeze-drying of polymeric spheres, and template-assisted approaches have also been developed. It is attractive but still challenging to fabricate BNPs due to their unique structural features. However, there is still no comprehensive summary of BNPs up to now, which significantly hinders the further development of this field. In this review, the recent progress of BNPs will be highlighted from the perspectives of design strategies, preparation methods, formation mechanisms, and emerging applications. Moreover, the future perspectives of BNPs will also be proposed.

MicroRNA therapeutics and nucleic acid nano-delivery systems in bacterial infection: a review

Bacteria that have worked with humans for thousands of years pose a major threat to human health even today, as drug resistance has become a prominent problem. Compared to conventional drug therapy, nucleic acid-based therapies are a promising and potential therapeutic strategy for diseases in which nucleic acids are delivered through a nucleic acid delivery system to regulate gene expression in specific cells, offering the possibility of curing intractable diseases that are difficult to treat at this stage. Among the many nucleic acid therapeutic ideas, microRNA, a class of small nucleic acids with special properties, has made great strides in biology and medicine in just over two decades, showing promise in preclinical drug development. In this review, we introduce recent advances in nucleic acid delivery systems and their clinical applications, highlighting the potential of nucleic acid therapies, especially miRNAs extracted from traditional herbs, in combination with the existing set of nucleic acid therapeutic systems, to potentially open up a new line of thought in the treatment of cancer, viruses, and especially bacterial infectious diseases.

Core-Shell Polymeric Nanostructures with Intracellular ATP-Fueled dsRNA Delivery toward Genetic Control of Insect Pests

Transgenic RNA interference (RNAi) represents a burgeoning and promising alternative avenue to manage plant diseases and insect pests in plants. Nonviral nanostructured dsRNA carriers have been demonstrated to possess great potential to facilitate the application of RNAi. However, it remains a critical challenge to achieve the targeted and effective release of dsRNA into the pest cells, limiting the efficiency of the biological control of pests and diseases in practical applications. In this study, we designed and constructed a new type of core-shell polymeric nanostructure (CSPN) with controllable structure, eco-friendliness, and good biocompatibility, on which dsRNA can be efficiently loaded. Once loaded into CSPNs, the dsRNA can be effectively prevented from nonsense degradation by enzymes before entering cells, and it shows targeted and image-guided release triggered by intracellular ATP, which significantly increases the efficiency of gene transfection. Significantly, the in vivo study of the typical lepidoptera silkworm after oral feeding demonstrates the potential of dsCHT10 in CSPNs for a much better knockdown efficiency than that of naked dsCHT10. This innovation enables the nanotechnology developed for the disease microenvironment-triggered release of therapeutic genes for application in sustainable crop protection.

Co-Delivery of paclitaxel and doxorubicin in folate-Targeted pluronic/ploy (D,L-lactide-b-glycolide) polymersomes

Drugs with different solubility can be selectively embedded into polymersomes with the hydrophilic core and hydrophobic bilayer. Novel folate-targeted Pluronic/poly (D,L-lactide-b-glycolide) polymersomes were constructed and used for the co-delivery of paclitaxel (PTX) and doxorubicin (DOX) to improve their inhibitory effect over cancer cells. The particle size of blank polymersomes was mainly distributed below 125 nm. The release of PTX and DOX from polymersomes showed an initial burst release followed by a sustained and slow release. The in vitro cytotoxicity data showed that the targeted co-loaded polymersomes (PTX&DOX FA-Ps) exhibited better inhibitory effect than single-loaded polymersomes and free drugs did. Furthermore, PTX&DOX FA-Ps showed the synergistic therapeutic effect over OVCAR-3 cancer cells. The cellular uptake results also showed that folate modified polymersomes had excellent targeting performance. Therefore, the folate-targeted Pluronic/poly (D,L-lactide-b-glycolide) polymersomes have potential application value as novel drug carriers to co-deliver PTX and DOX.

Phase separation in polymer-based biomimetic structures containing planar membranes

Phase separation in biological membranes is crucial for proper cellular functions, such as signaling and trafficking, as it mediates the interactions of condensates on membrane-bound organelles and transmembrane transport to targeted destination compartments. The separation of a lipid bilayer into phases and the formation of lipid rafts involve the restructuring of molecular localization, their immobilization, and local accumulation. By understanding the processes underlying the formation of lipid rafts in a cellular membrane, it is possible to reconstitute this phenomenon in synthetic biomimetic membranes, such as hybrids of lipids and polymers or membranes composed solely of polymers, which offer an increased physicochemical stability and unlimited possibilities of chemical modification and functionalization. In this article, we relate the main lipid bilayer phase transition phenomenon with respect to hybrid biomimetic membranes, composed of lipids mixed with polymers, and fully synthetic membranes. Following, we review the occurrence of phase separation in biomimetic hybrid membranes based on lipids and/or direct lipid analogs, amphiphilic block copolymers. We further exemplify the phase separation and the resulting properties and applications in planar membranes, free-standing and solid-supported. We briefly list methods leading to the formation of such biomimetic membranes and reflect on their improved overall stability and influence on the separation into different phases within the membranes. Due to the importance of phase separation and compartmentalization in cellular membranes, we are convinced that this compiled overview of this phenomenon will be helpful for any researcher in the biomimicry area.

Intelligent design of polymersomes for antibacterial and anticancer applications

Polymersomes (or polymer vesicles) have attracted much attention for biomedical applications in recent years because their lumen can be used for drug delivery and their coronas and membrane can be modified with a variety of functional groups. Thus, polymersomes are very suitable for improved antibacterial and anticancer therapy. This review mainly highlighted recent advances in the synthetic protocols and design principles of intelligent antibacterial and anticancer polymersomes. Antibacterial polymersomes are divided into three categories: polymersomes as antibiotic nanocarriers, intrinsically antibacterial polymersomes, and antibacterial polymersomes with supplementary means including photothermal and photodynamic therapy. Similarly, the anticancer polymersomes are divided into two categories: polymersomes-based delivery systems and anticancer polymersomes with supplementary means. In addition, the bilateral relationship between bacteria and cancer is addressed, since more and more evidences show that bacteria may cause cancer or promote cancer progression. Finally, prospective on next-generation antibacterial and anticancer polymersomes are discussed. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Biology-Inspired Nanomaterials > Lipid-Based Structures.

Current Perspectives on Synthetic Compartments for Biomedical Applications

Nano- and micrometer-sized compartments composed of synthetic polymers are designed to mimic spatial and temporal divisions found in nature. Self-assembly of polymers into compartments such as polymersomes, giant unilamellar vesicles (GUVs), layer-by-layer (LbL) capsules, capsosomes, or polyion complex vesicles (PICsomes) allows for the separation of defined environments from the exterior. These compartments can be further engineered through the incorporation of (bio)molecules within the lumen or into the membrane, while the membrane can be decorated with functional moieties to produce catalytic compartments with defined structures and functions. Nanometer-sized compartments are used for imaging, theranostic, and therapeutic applications as a more mechanically stable alternative to liposomes, and through the encapsulation of catalytic molecules, i.e., enzymes, catalytic compartments can localize and act in vivo. On the micrometer scale, such biohybrid systems are used to encapsulate model proteins and form multicompartmentalized structures through the combination of multiple compartments, reaching closer to the creation of artificial organelles and cells. Significant progress in therapeutic applications and modeling strategies has been achieved through both the creation of polymers with tailored properties and functionalizations and novel techniques for their assembly.

Polymer Micelles vs Polymer-Lipid Hybrid Vesicles: A Comparison Using RAW 264.7 Cells

Bottom-up synthetic biology aims to integrate artificial moieties with living cells and tissues. Here, two types of structural scaffolds for artificial organelles were compared in terms of their ability to interact with macrophage-like murine RAW 264.7 cells. The amphiphilic block copolymer poly(cholesteryl methacrylate)-block-poly(2-carboxyethyl acrylate) was used to assemble micelles and polymer-lipid hybrid vesicles together with 1,2-dioleoyl-sn-glycero-3-phosphocholine or 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) lipids in the latter case. In addition, the pH-sensitive fusogenic peptide GALA was conjugated to the carriers to improve their lysosomal escape ability. All assemblies had low short-term toxicity toward macrophage-like murine RAW 264.7 cells, and the cells internalized both the micelles and hybrid vesicles within 24 h. Assemblies containing DOPE lipids or GALA in their building blocks could escape the lysosomes. However, the intracellular retention of the building blocks was only a few hours in all the cases. Taken together, the provided comparison between two types of potential scaffolds for artificial organelles lays out the fundamental understanding required to advance soft material-based assemblies as intracellular nanoreactors.

Polymeric Nanomaterials for Efficient Delivery of Antimicrobial Agents

Bacterial infections have threatened the lives of human beings for thousands of years either as major diseases or complications. The elimination of bacterial infections has always occupied a pivotal position in our history. For a long period of time, people were devoted to finding natural antimicrobial agents such as antimicrobial peptides (AMPs), antibiotics and silver ions or synthetic active antimicrobial substances including antimicrobial peptoids, metal oxides and polymers to combat bacterial infections. However, with the emergence of multidrug resistance (MDR), bacterial infection has become one of the most urgent problems worldwide. The efficient delivery of antimicrobial agents to the site of infection precisely is a promising strategy for reducing bacterial resistance. Polymeric nanomaterials have been widely studied as carriers for constructing antimicrobial agent delivery systems and have shown advantages including high biocompatibility, sustained release, targeting and improved bioavailability. In this review, we will highlight recent advances in highly efficient delivery of antimicrobial agents by polymeric nanomaterials such as micelles, vesicles, dendrimers, nanogels, nanofibers and so forth. The biomedical applications of polymeric nanomaterial-based delivery systems in combating MDR bacteria, anti-biofilms, wound healing, tissue engineering and anticancer are demonstrated. Moreover, conclusions and future perspectives are also proposed.

A Review on Polymer and Lipid-Based Nanocarriers and Its Application to Nano-Pharmaceutical and Food-Based Systems

Recently, owing to well-controlled release, enhanced distribution and increased permeability, nanocarriers used for alternative drug and food-delivery strategies have received increasingly attentions. Nanocarriers have attracted a large amount of interest as potential carriers of various bioactive molecules for multiple applications. Drug and food-based delivery via polymeric-based nanocarriers and lipid-based nanocarriers has been widely investigated. Nanocarriers, especially liposomes, are more and more widely used in the area of novel nano-pharmaceutical or food-based design. Herein, we aimed to discuss the recent advancement of different surface-engineered nanocarriers type, along with cutting-edge applications for food and nanomedicine and highlight the alternative of phytochemical as nanocarrier. Additionally, safety concern of nanocarriers was also highlighted.

Dendrimer-Based Polyion Complex Vesicles: Loops Make Loose

Associations of amphiphiles assume their various morphologies according to the so-called packing parameter under thermodynamic control. However, one may raise the question of whether polymers can always relax fast enough to obey thermodynamic control, and how this may be checked. Here, a case of polyion complex (PIC) assemblies where the morphology appears to be subject to kinetic control is discussed. Poly (ethylene oxide)-b-(styrene sulfonate) block copolymers are combined with cationic PAMAM dendrimers of various generations (2-7). The PEO-PSS diblocks, and the corresponding PSS-PEO-PSS triblocks should have nearly identical packing parameters, but surprisingly creat different assemblies, namely core-shell micelles and vesicles, respectively. Moreover, the micelles are very stable against added salt, whereas the vesicles are not only much more sensitive to added salt, but also appear to exchange matter on relevant time scales. The small and largely quenched early-stage precursor complexes are responsible for the morphological and dynamic differences, implying that kinetic control may also be a way to obtain particles with well-defined and useful properties. The exciting new finding that triblocks produce more "active" vesicles will hopefully trigger the exploration of more pathways, and so learn how to tune PICsomes toward specific applications.

Bone-Targeting Polymer Vesicles for Effective Therapy of Osteoporosis

With the aging of the population, postmenopausal osteoporosis becomes increasingly widespread and severe as fractures caused by osteoporosis may lead to permanent disabilities and even death. Inspired by extracellular vesicles that participate in bone remodeling, we present a biomimicking polymer vesicle for bone-targeted β-estradiol (E₂) delivery. This vesicle is self-assembled from a poly(ε-caprolactone)₂₈-block-poly[(l-glutamic acid)₇-stat-(l-glutamic acid-alendronic acid)₄] (PCL₂₈-b-P[Glu₇-stat-(Glu-ADA)₄]) diblock copolymer. The alendronic acid (ADA) on the coronas endows the polymer vesicles with a high bone affinity and acts synergistically with E₂ to achieve an enhanced therapeutic effect. As confirmed with ovariectomized osteoporosis rat models, bone loss was significantly reversed as the recovery rates of total BMD (bone mineral density) and trabecular BMD were 70.4% and 99.3%, respectively. Overall, this work provides fresh insight into the treatment of osteoporosis.

Polymer Vesicles for Antimicrobial Applications

Polymer vesicles, hollow nanostructures with hydrophilic cavity and hydrophobic membrane, have shown significant potentials in biomedical applications including drug delivery, gene therapy, cancer theranostics, and so forth, due to their unique cell membrane-like structure. Incorporation with antibacterial active components like antimicrobial peptides, etc., polymer vesicles exhibited enhanced antimicrobial activity, extended circulation time, and reduced cell toxicity. Furthermore, antibacterial, and anticancer can be achieved simultaneously, opening a new avenue of the antimicrobial applications of polymer vesicles. This review seeks to highlight the state-of-the-art of antimicrobial polymer vesicles, including the design strategies and potential applications in the field of antibacterial. The structural features of polymer vesicles, preparation methods, and the combination principles with antimicrobial active components, as well as the advantages of antimicrobial polymer vesicles, will be discussed. Then, the diverse applications of antimicrobial polymer vesicles such as wide spectrum antibacterial, anti-biofilm, wound healing, and tissue engineering associated with their structure features are presented. Finally, future perspectives of polymer vesicles in the field of antibacterial is also proposed.

Giant Polymer Vesicles with a Latticelike Membrane

Hierarchical self-assembly offers great possibilities to mimic biological systems with finely arranged complex structures. Herein, we demonstrate the preparation and formation mechanism of an unusual giant polymer vesicle with a latticelike membrane (GVLM). This GVLM is formed by fusion-induced particle assembly (FIPA) of small vesicles that are self-assembled from poly(ethylene oxide)-block-poly[(2-(tetrahydrofuranyloxy)ethyl methacrylate)-stat-(6-(3,3-diphenylnaphthopyranyloxy)hexyl methacrylate)] [PEO₄₃-b-P(TMA₂₂-stat-NMA₄)]. Flexible TMA units with high chain mobility and relatively rigid NMA units with intrinsic π-π stacking form the hydrophobic block. These units act as "antifusion" and "profusion" components, respectively. The latticelike membrane of the final GVLM consists of hundreds of small polymer vesicles that are interconnected via multiple interactions. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) studies show that the diameter of the GVLMs is 800-1000 nm. Overall, we provide a new insight into the judicious preparation of hierarchical nanostructures via chemical synthesis and FIPA.

Asymmetric Vesicles Self-Assembled by Amphiphilic Sequence-Controlled Polymers

The asymmetric distribution of lipids on the inner and outer membranes of a cell plays a pivotal role in the physiological and immunological activities of life. It has inspired the elaboration of synthetic asymmetric vesicles for the discovery of advanced materials and functions. The asymmetric vesicles were generally prepared by amphiphilic block copolymers. We herein report on the formation of asymmetric vesicles self-assembled by amphiphilic sequence-controlled polymers with two hydrophilic segments SU and TEO. We also developed an efficient fluorescence titration method with europium(III) ions (Eu³⁺) to determine the uneven distribution of SU and TEO. SU units are preferentially located on the outer membrane and TEO on the inner membrane of the resulting vesicles, which is facilitated by the electrostatic repulsion of SU and the U-shaped folding of the hydrophobic backbone of the resulting polymers. This work shows that sequence-controlled polymers with alternating monomer sequence provide a powerful toolbox for the elaboration of important yet challenging self-assembled structures for emerging functions and properties.

Therapeutic nanoreactors for detoxification of xenobiotics: Concepts, challenges and biotechnological trends with special emphasis to organophosphate bioscavenging

The introduction of enzyme nanoreactors in medicine is relatively new. However, this technology has already been experimentally successful in cancer treatments, struggle against toxicity of reactive oxygen species in inflammatory processes, detoxification of drugs and xenobiotics, and correction of metabolic and genetic defects by using encapsulated enzymes, acting in single or cascade reactions. Biomolecules, e.g. enzymes, antibodies, reactive proteins capable of inactivating toxicants in the body are called bioscavengers. In this review, we focus on enzyme-containing nanoreactors for in vivo detoxification of organophosphorous compounds (OP) to be used for prophylaxis and post-exposure treatment of OP poisoning. A particular attention is devoted to bioscavenger-containing injectable nanoreactors operating in the bloodstream. The nanoreactor concept implements single or multiple enzymes and cofactors co-encapsulated in polymeric semi-permeable nanocontainers. Thus, the detoxification processes take place in a confined space containing highly concentrated bioscavengers. The article deals with historical and theoretical backgrounds about enzymatic detoxification of OPs in nanoreactors, nanoreactor polymeric enveloppes, realizations and advantages over other approaches using bioscavengers.

Ultrasound-responsive polymer-based drug delivery systems

Ultrasound-responsive polymeric materials have received a tremendous amount of attention from scientists for several decades. Compared to other stimuli-responsive materials (such as UV-, thermal-, and pH-responsive materials), these smart materials are more applicable since they allow more efficient drug delivery and targeted treatment by fairly non-invasive means. This review describes the recent advances of such ultrasound-responsive polymer-based drug delivery systems and illustrates various applications. More specifically, the mechanism of ultrasound-induced drug delivery, typical formulations, and biomedical applications (tumor therapy, disruption of blood-brain barrier, fighting infectious diseases, transdermal drug delivery, and enhanced thrombolysis) are summarized. Finally, a perspective on the future research directions for the development of ultrasound-responsive polymeric materials to facilitate a clinical translation is given.

High-genus multicompartment vesicles evolved from large compound micelles

High-genus multicompartment vesicles (HGMVs) are self-assembled from block copolymers containing fluorescent and photo-responsive azobenzene groups.