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Jan C. M. Van Hest - One of the best experts on this subject based on the ideXlab platform.
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Adaptive Polymersome nanoreactors
ChemNanoMat, 2019Co-Authors: Hailong Che, Jan C. M. Van HestAbstract:Adaptive Polymersome systems have gained much interest in a wide variety of research fields, ranging from cell mimics to nanomedicine, because of their high stability, tuneable shape and size. Furthermore, Polymersomes can be effectively transformed into nanoreactors via the incorporation of catalytic species. By employing Polymersomes which are adaptive in structure and function the features of Polymersome nanoreactors can be even further extended. In this review, we focus on recent impressive developments of smart Polymersomes as functional nanoreactors with an emphasis on the type of adaptivity that is installed, which includes intrinsic permeability, stimuli‐responsiveness and self‐adaptivity. Moreover, particular attention is given to the utility of Polymersome nanoreactors in vitro and in vivo, which paves the next step forward towards the engineering of artificial organelles as therapeutic materials.
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feedback induced temporal control of breathing Polymersomes to create self adaptive nanoreactors
Journal of the American Chemical Society, 2018Co-Authors: Hailong Che, Shoupeng Cao, Jan C. M. Van HestAbstract:Here we present the development of self-regulated “breathing” Polymersome nanoreactors that show temporally programmable biocatalysis induced by a chemical fuel. pH-sensitive Polymersomes loaded with horseradish peroxidase (HRP) and urease were developed. Addition of an acidic urea solution (“fuel”) endowed the Polymersomes with a transient size increase and permeability enhancement, driving a temporal “ON” state of the HRP enzymatic catalysis; subsequent depletion of fuel led to shrinking of the Polymersomes, resulting in the catalytic “OFF” state. Moreover, the nonequilibrium nanoreactors could be reinitiated several cycles as long as fuel was supplied. This feedback-induced temporal control of catalytic activity in Polymersome nanoreactors provides a platform for functional nonequilibrium systems as well as for artificial organelles with precisely controlled adaptivity.
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Feedback-Induced Temporal Control of “Breathing” Polymersomes To Create Self-Adaptive Nanoreactors
2018Co-Authors: Hailong Che, Shoupeng Cao, Jan C. M. Van HestAbstract:Here we present the development of self-regulated “breathing” Polymersome nanoreactors that show temporally programmable biocatalysis induced by a chemical fuel. pH-sensitive Polymersomes loaded with horseradish peroxidase (HRP) and urease were developed. Addition of an acidic urea solution (“fuel”) endowed the Polymersomes with a transient size increase and permeability enhancement, driving a temporal “ON” state of the HRP enzymatic catalysis; subsequent depletion of fuel led to shrinking of the Polymersomes, resulting in the catalytic “OFF” state. Moreover, the nonequilibrium nanoreactors could be reinitiated several cycles as long as fuel was supplied. This feedback-induced temporal control of catalytic activity in Polymersome nanoreactors provides a platform for functional nonequilibrium systems as well as for artificial organelles with precisely controlled adaptivity
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shape characterization of Polymersome morphologies via light scattering techniques
Polymer, 2016Co-Authors: Loai K E A Abdelmohsen, Jan C. M. Van Hest, Peter C. M. Christianen, Roger S. M. Rikken, Daniela A. WilsonAbstract:Polymersomes, vesicles self-assembled from amphiphilic block copolymers, are well known for their robustness and for their broad applicability. Generating Polymersomes of different shape is a topic of recent attention, specifically in the field of biomedical applications. To obtain information about their exact shape, tomography based on cryo-electron microscopy is usually the most preferred technique. Unfortunately, this technique is rather time consuming and expensive. Here we demonstrate an alternative analytical approach for the characterization of differently shaped Polymersomes such as spheres, prolates and discs via the combination of multi-angle light scattering (MALS) and quasi-elastic light scattering (QELS). The use of these coupled techniques allowed for accurate determination of both the radius of gyration (Rg) and the hydrodynamic radius (Rh). This afforded us to determine the shape ratio ρ (Rg/Rh) with which we were able to distinguish between Polymersome spheres, discs and rods.
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aqueous asymmetric aldol reactions in Polymersome membranes
Polymer Chemistry, 2015Co-Authors: Matthijs C M Van Oers, Jan C. M. Van Hest, Wouter S Veldmate, Floris P. J. T. RutjesAbstract:L-Proline catalysts have been immobilised in the hydrophobic domain of a Polymersome via a copper(I)-catalysed azide–alkyne cycloaddition (CuAAC) reaction. Utilisation of these nanoreactors in the asymmetric aldol reaction of cyclohexanone with 4-nitrobenzaldehyde afforded the corresponding β-hydroxyketones in quantitative yields and with excellent enantio- and diastereoselectivities. The Polymersomes were recycled up to five times without any loss in activity or selectivity.
Daniel A. Hammer - One of the best experts on this subject based on the ideXlab platform.
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Enzymatically triggered rupture of Polymersomes
Soft matter, 2016Co-Authors: Woo-sik Jang, Seung Chul Park, Ellen H. Reed, Kevin P. Dooley, Samuel F. Wheeler, Daeyeon Lee, Daniel A. HammerAbstract:Polymersomes are robust vesicles made from amphiphilic block co-polymers. Large populations of uniform giant Polymersomes with defined, entrapped species can be made by templating of double-emulsions using microfluidics. In the present study, a series of two enzymatic reactions, one inside and the other outside of the Polymersome, were designed to induce rupture of Polymersomes. We measured how the kinetics of rupture were affected by altering enzyme concentration. These results suggest that protocells with entrapped enzymes can be engineered to secrete contents on cue.
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Engineering Polymersome Protocells.
The journal of physical chemistry letters, 2011Co-Authors: Neha P. Kamat, Joshua S. Katz, Daniel A. HammerAbstract:The field of biomimicry is embracing the construction of complex assemblies that imitate both biological structure and function. Advancements in the design of these mimetics have generated a growing vision for creating an artificial cell or protocell. Polymersomes are vesicles that can be made from synthetic, biological, or hybrid polymers and can be used as a model template to build cell-like structures. In this perspective, we discuss various areas where Polymersomes have been used to mimic cell functions as well as areas in which the synthetic flexibility of Polymersomes would make them ideal candidates for a biomembrane mimetic. Designing a Polymersome that comprehensively displays the behaviors discussed herein has the potential to lead to the development of an autonomous, responsive particle that resembles the intelligence of a biological cell.
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A Generalized System for Photoresponsive Membrane Rupture in Polymersomes
Advanced functional materials, 2010Co-Authors: Neha P. Kamat, Michael J. Therien, Gregory P. Robbins, Jeff Rawson, Ivan J. Dmochowski, Daniel A. HammerAbstract:Polymersomes are vesicles whose membranes comprise self-assembled block copolymers. It has recently been shown that co-encapsulating conjugated multiporphyrin dyes in a Polymersome membrane with ferritin protein in the aqueous lumen confers photolability to the Polymersome. In the present study, the photolability is shown to be extendable to vesicles containing dextran, an inert and inexpensive polysaccharide, as the luminal solute. How structural features of the Polymersome/porphyrin/dextran composite affect its photoresponse is explored. Increasing dextran molecular weight, decreasing block copolymer molecular weight, and altering fluorophore-membrane interactions results in increasing the photoresponsiveness of the Polymersomes. Amphiphilic interactions of the luminal encapsulant with the membrane coupled with localized heat production in the hydrophobic bilayer likely cause differential thermal expansion in the membrane and the subsequent membrane rupture. This study suggests a general approach to impart photoresponsiveness to any biomimetic vesicle system without chemical modification, as well as a simple, bio-inert method for constructing photosensitive carriers for controlled release of encapsulants.
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Membrane stabilization of biodegradable Polymersomes.
Langmuir : the ACS journal of surfaces and colloids, 2009Co-Authors: Joshua S. Katz, Dalia H. Levine, Kevin P. Davis, Frank S. Bates, Daniel A. Hammer, Jason A. BurdickAbstract:Biodegradable Polymersomes are promising vehicles for a range of applications. Their stabilization would improve many properties, including the retention and controlled release of Polymersome contents, yet this has not been previously accomplished. Here, we present the first example of stabilizing fully biodegradable Polymersomes through acrylation of the hydrophobic terminal end of Polymersome-forming poly(caprolactone-b-ethylene glycol). Exposure of the resulting Polymersomes loaded with a hydrophobic photoinitiator to ultraviolet light polymerized the acrylates, without affecting Polymersome morphology or cell cytotoxicity. These stabilized Polymersomes were more resistant to surfactant disruption and degradation. As an example of stabilized Polymersome utility, the unintended release of doxorubicin (DOX) due to leakage from Polymersomes decreased with membrane stabilization and slower sustained release was observed. Finally, DOX-loaded Polymersomes retained their cytotoxicity following stabilization.
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Polymersomes: A new multi-functional tool for cancer diagnosis and therapy
Methods (San Diego Calif.), 2008Co-Authors: Dalia H. Levine, Daniel A. Hammer, P. Peter Ghoroghchian, Jaclyn A. Freudenberg, Geng Zhang, Michael J. Therien, Mark I. Greene, Ramachandran MuraliAbstract:Nanoparticles are being developed as delivery vehicles for therapeutic pharmaceuticals and contrast imaging agents. Polymersomes (mesoscopic polymer vesicles) possess a number of attractive biomaterial properties that make them ideal for these applications. Synthetic control over block copolymer chemistry enables tunable design of Polymersome material properties. The Polymersome architecture, with its large hydrophilic reservoir and its thick hydrophobic lamellar membrane, provides significant storage capacity for both water soluble and insoluble substances (such as drugs and imaging probes). Further, the brush-like architecture of the Polymersome outer shell can potentially increase biocompatibility and blood circulation times. A further recent advance is the development of multi-functional Polymersomes that carry pharmaceuticals and imaging agents simultaneously. The ability to conjugate biologically active ligands to the brush surface provides a further means for targeted therapy and imaging. Hence, Polymersomes hold enormous potential as nanostructured biomaterials for future in vivo drug delivery and diagnostic imaging applications.
Kyoung Taek Kim - One of the best experts on this subject based on the ideXlab platform.
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cross linked Polymersomes with reversible deformability and oxygen transportability
Biomacromolecules, 2019Co-Authors: Ji Won Kim, Sungwoo Jeong, Roman Korneev, Kwanwoo Shin, Kyoung Taek KimAbstract:Polymersomes are of interest as nanocarriers due to their physical and chemical robustness, which arises from the macromolecular nature of their block copolymer components. However, the physical robustness of Polymersomes impairs transmembrane diffusion and responsiveness to mechanical forces. Polymer nanocarriers that can reversibly deform under stress while maintaining structural integrity and transmembrane diffusivity are desired for development of gas transport vehicles. Here, we report Polymersomes composed of amphiphilic block copolymers containing polydimethylsiloxane with side-chain pendant vinyl groups. A reversibly deformable Polymersome compartmentalizing membrane was obtained by cross-linkage of PEG- b-poly(dimethyl- r-methylvinyl)silane in a self-assembled bilayer via photoradical generation in aqueous media. The covalently cross-linked Polymersomes exhibited superior physical robustness compared to unlinked Polymersomes while maintaining deformability under stress. Transmembrane oxygen diffusion was confirmed when lumen-encapsulated Zn-porphyrin generated singlet O2 under irradiation, and the anthracene-9,10-dipropionic acid O2 quencher was consumed. Polymersome-encapsulated hemoglobin bound oxygen reversibly, indicating the Polymersomes could be used as O2 carriers that reversibly deform without sacrificing structural integrity or oxygen transportability.
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Cross-Linked Polymersomes with Reversible Deformability and Oxygen Transportability
2019Co-Authors: Ji Won Kim, Sungwoo Jeong, Roman Korneev, Kwanwoo Shin, Kyoung Taek KimAbstract:Polymersomes are of interest as nanocarriers due to their physical and chemical robustness, which arises from the macromolecular nature of their block copolymer components. However, the physical robustness of Polymersomes impairs transmembrane diffusion and responsiveness to mechanical forces. Polymer nanocarriers that can reversibly deform under stress while maintaining structural integrity and transmembrane diffusivity are desired for development of gas transport vehicles. Here, we report Polymersomes composed of amphiphilic block copolymers containing polydimethylsiloxane with side-chain pendant vinyl groups. A reversibly deformable Polymersome compartmentalizing membrane was obtained by cross-linkage of PEG-b-poly(dimethyl-r-methylvinyl)silane in a self-assembled bilayer via photoradical generation in aqueous media. The covalently cross-linked Polymersomes exhibited superior physical robustness compared to unlinked Polymersomes while maintaining deformability under stress. Transmembrane oxygen diffusion was confirmed when lumen-encapsulated Zn–porphyrin generated singlet O2 under irradiation, and the anthracene-9,10-dipropionic acid O2 quencher was consumed. Polymersome-encapsulated hemoglobin bound oxygen reversibly, indicating the Polymersomes could be used as O2 carriers that reversibly deform without sacrificing structural integrity or oxygen transportability
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a Polymersome nanoreactor with controllable permeability induced by stimuli responsive block copolymers
Advanced Materials, 2009Co-Authors: Kyoung Taek Kim, Jeroen J L M Cornelissen, Roeland J. M. Nolte, Jan C. M. Van HestAbstract:A method to generate and control the permeability of Polymersome membranes using mixtures of amphiphilic and stimuli-responsive boronic acid-containing block copolymers is reported. The latter block copolymers form phase-separated domains in the Polymersomes, which can be dissolved by increasing the pH of the medium or by introducing sugar molecules that covalently bind to the boronic acid moieties.
Daniela A. Wilson - One of the best experts on this subject based on the ideXlab platform.
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Modular Approach to the Functionalization of Polymersomes
Biomacromolecules, 2020Co-Authors: Sjoerd J Rijpkema, Sabine G H A Langens, Marnix R Van Der Kolk, Katerina Gavriel, B. Jelle Toebes, Daniela A. WilsonAbstract:Functionalizing Polymersomes remains a challenge due to the limitation in reaction conditions applicable to the chemistry on the surface, hindering their application for selective targeting. In order to overcome this limitation, functionalization can be introduced right before the self-assembly. Here, we have synthesized a library (32 examples) of PEG-b-PS and PEG-b-PDLLA with various functional groups derived from the amine-functionalized polymers, leading to functionally active Polymersomes. We show that Polymersome formation is possible via the general method with all functionalized groups and that these handles are present on the surface and are able to undergo reactions. Additionally, this methodology provides a general synthetic tool to tailor the functional group of the Polymersome right before self-assembly, without limitation on the reaction conditions.
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Tailoring Polymersome Shape Using the Hofmeister Effect
Biomacromolecules, 2019Co-Authors: Yongjun Men, Coralie Lebleu, Jiawei Sun, Daniela A. WilsonAbstract:Reshaping Polymersomes remains a challenge for both size and shape control, methodology development, and mechanism understanding, which hindered their application in nanomedicine and nanomachine. Unlike liposome, Polymersomes are capable of maintaining their shape due to their rigid and glassy membrane. Here we use the Hofmeister effect to guide the shape control of Polymersome by tuning the ion type and concentration. Multiple morphologies such as ellipsoid, tube, disc, stomatocytes, and large compound vesicles are found. These results give evidence of demonstrating that the shape changes are not only induced by osmotic pressure, but also by the interaction with the Polymersome membranes. Additionally, this methodology provides a general tool to tailor the shape of Polymersome into various morphologies.
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shape characterization of Polymersome morphologies via light scattering techniques
Polymer, 2016Co-Authors: Loai K E A Abdelmohsen, Jan C. M. Van Hest, Peter C. M. Christianen, Roger S. M. Rikken, Daniela A. WilsonAbstract:Polymersomes, vesicles self-assembled from amphiphilic block copolymers, are well known for their robustness and for their broad applicability. Generating Polymersomes of different shape is a topic of recent attention, specifically in the field of biomedical applications. To obtain information about their exact shape, tomography based on cryo-electron microscopy is usually the most preferred technique. Unfortunately, this technique is rather time consuming and expensive. Here we demonstrate an alternative analytical approach for the characterization of differently shaped Polymersomes such as spheres, prolates and discs via the combination of multi-angle light scattering (MALS) and quasi-elastic light scattering (QELS). The use of these coupled techniques allowed for accurate determination of both the radius of gyration (Rg) and the hydrodynamic radius (Rh). This afforded us to determine the shape ratio ρ (Rg/Rh) with which we were able to distinguish between Polymersome spheres, discs and rods.
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Probing morphological changes in Polymersomes with magnetic birefringence
Chemical Communications, 2013Co-Authors: Roger S. M. Rikken, Roeland J. M. Nolte, Jan C. M. Van Hest, Peter C. M. Christianen, Jan C. Maan, Harmen H. M. Kerkenaar, Daniela A. WilsonAbstract:Magnetic birefringence was used for in situ monitoring of the morphological changes in diamagnetic Polymersomes during shape-transformation by dialysis. The birefringence was found to be very sensitive to the Polymersome morphology, as determined by electron microscopy. The deflation of Polymersomes into disks was observed, followed by a bending and partial inflation into stomatocytes.
Giuseppe Battaglia - One of the best experts on this subject based on the ideXlab platform.
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Stability of Polymersomes prepared by size exclusion chromatography and extrusion
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2016Co-Authors: Julia E. Bartenstein, Giuseppe Battaglia, James D. Robertson, Wuge H. BriscoeAbstract:In this work, stability of poly(butadiene)-poly(ethylene oxide) (PBD-PEO) Polymersomes, self-assembled from two polymers with different molecular weights (PBD32-PEO21 and PBD125-PEO80) in either pure H2O or phosphate buffered saline (PBS), is studied. Polymersome dispersions usually show large polydispersity, and it is thus desirable to separate different-sized vesicles if a narrow size distribution is required, e.g. for model systems in certain applications. This is typically achieved by extrusion through a membrane with a designated pore size or, less commonly, by size exclusion chromatography (SEC). Here, we find that both extrusion and SEC of Polymersome dispersions with vesicle sizes ranging from 100 to 5000 nm and polydispersity index (PDI) = 1, can yield smaller vesicles with PDIs < 0.35. With SEC, it is possible to separate fractions of Polymersomes with different sizes. However, the SEC Polymersome size and particularly the spread in the size increase significantly over time, whereas the extruded Polymersomes are shown to be more stable. We attribute this to possible dilution of the Polymersome dispersion during the SEC elusion process. The effects of temperature and the PBD-PEO molecular weight on the stability of the extruded Polymersomes against dilution in pure water and phosphate buffer are further studied. It is found that the Polymersomes show higher stability when stored at lower temperature, undiluted, and prepared in phosphate buffer, whereas the polymer molecular weight does not have a large influence on the stability.
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Polymersome mediated intracellular delivery of antibiotics to treat porphyromonas gingivalis infected oral epithelial cells
The FASEB Journal, 2013Co-Authors: Kornchanok Wayakanon, Giuseppe Battaglia, Nicholas J Warren, Steven P Armes, Martin H Thornhill, C Ian W Douglas, Andrew L Lewis, Abigail Pinnock, Craig MurdochAbstract:The gram-negative anaerobe Porphyromonas gingivalis colonizes the gingival crevice and is etiologically associated with periodontal disease that can lead to alveolar bone damage and resorption, promoting tooth loss. Although susceptible to antibiotics, P. gingivalis can evade antibiotic killing by residing within gingival keratinocytes. This provides a reservoir of organisms that may recolonize the gingival crevice once antibiotic therapy is complete. Polymersomes are nanosized amphiphilic block copolymer vesicles that can encapsulate drugs. Cells internalize Polymersomes by endocytosis into early endosomes, where they are disassembled by the low pH, causing intracellular release of their drug load. In this study, Polymersomes were used as vehicles to deliver antibiotics in an attempt to kill intracellular P. gingivalis within monolayers of keratinocytes and organotypic oral mucosal models. Polymersome-encapsulated metronidazole or doxycycline, free metronidazole, or doxycycline, or Polymersomes alone as controls, were used, and the number of surviving intracellular P. gingivalis was quantified after host cell lysis. Polymersome-encapsulated metronidazole or doxycycline significantly (P<0.05) reduced the number of intracellular P. gingivalis in both monolayer and organotypic cultures compared to free antibiotic or Polymersome alone controls. Polymersomes are effective delivery vehicles for antibiotics that do not normally gain entry to host cells. This approach could be used to treat recurrent periodontitis or other diseases caused by intracellular-dwelling organisms.
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Encapsulation of Biomacromolecules within Polymersomes by Electroporation
Angewandte Chemie (International ed. in English), 2012Co-Authors: Linge Wang, Jeppe Madsen, Steven P Armes, Luca Chierico, Daniel Little, Nisa Patikarnmonthon, Zhou Yang, Mimoun Azzouz, Giuseppe BattagliaAbstract:Abstract Biological macromolecules can be encapsulated into preformed Polymersomes by controlled temporary destabilization of the vesicle membrane. The morphology and the size of the Polymersome are unchanged after electroporation, suggesting that the Polymersome membrane is reformed. The surface charge of the biomacromolecules plays a key role for the electroporation process.
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Nanotechnologies for the Life Sciences - Polymersomes and Their Biomedical Applications
Nanotechnologies for the Life Sciences, 2012Co-Authors: Giuseppe BattagliaAbstract:The sections in this article are Introduction The Chemistry of Polymersomes Polymersomes: Physico-Chemical Properties Membrane Conformations Responsive Polymersomes Surface Chemistry of the Polymersomes Polymersomes Formation and Preparation Biomedical Applications Medical Imaging Cancer Therapy Polymersomes as Delivery Vectors Nanoreactors Artificial Cells and Organelles Gene Therapy Conclusions Keywords: Polymersome; block copolymers; vesicle; drug delivery; gene delivery; encapsulation
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Polymersome production on a microfluidic platform using ph sensitive block copolymers
Lab on a Chip, 2010Co-Authors: Luke Brown, Andrew L Lewis, Sally L Mcarthur, Phillip C Wright, Giuseppe BattagliaAbstract:Development of pH sensitive biocompatible block copolymer Polymersomes, which are stable in physiological conditions, is enabling the intracellular delivery of water soluble drugs and proteins. As a result, it is becoming increasingly important to develop robust production methods to enhance the Polymersome encapsulation efficiency. One way that this could be achieved is through production in microfluidic devices that potentially offer more favourable conditions for encapsulation. Here a flow focussing microfluidic device is used to induce self-assembly of poly(2-(methacryloyloxy)ethyl phosphorylcholine)–poly(2-(diisopropylamino)ethyl methacrylate) (PMPC-b-PDPA) block copolymer by changing the pH of the flows within the microchannels. The laminar flow conditions within the device result in a pH gradient at either interface of the central flow, where diffusion of hydrogen ions enables the deprotonation of the PDPA block copolymer and results in self-assembly of Polymersomes. Dynamic light scattering reveals hydrodynamic diameters in the range of 75–275 nm and double membrane structures visualized using transmission electron microscopy indicate that Polymersome nanostructures are being produced. The encapsulation efficiency for Bovine Serum Albumin (BSA) was calculated by measuring the spectroscopic absorbance at 279 nm and indicates that the encapsulation efficiency produced in the microfluidic device is equivalent to the standard in solution production method. Critically, the microfluidic system eliminates the use of organic solvents, which limit biological applications, through the pH induced self-assembly process and offers a continuous production method for intracellular delivery Polymersomes.