Search results for "Polymersome"

Continuously manufactured magnetic polymersomes--a versatile tool (not only) for targeted cancer therapy.

2013

Micromixer technology was used to prepare polymeric vesicles (Pluronic® L-121) dual loaded with the anti-cancer drug camptothecin and magnetic nanoparticles. Successful incorporation of the magnetic nanoparticles was confirmed by transmission electron microscopy. Dynamic light scattering measurements showed a relatively narrow size distribution of the hybrid polymersomes. Camptothecin polymersomes reduced the cell viability of prostate cancer cells (PC-3) measured after 72 h significantly, while drug-free polymersomes showed no cytotoxic effects. Covalent attachment of a cancer targeting peptide (bombesin) as well as a fluorescent label (Alexa Fluor® 647) to the hybrid polymersomes was perf…

Multifunctional nanocarriers for biomedical applications

2013

Polymeric vesicles (Pluronic ® L-121) loaded with magnetic nanoparticles (MNP) and an anti-cancer drug (camptothecin) were prepared continuously in a micro mixing device. Characterization by TEM confirmed the successful incorporation of the MNP and DLS measurements showed a relatively narrow size distribution of the hybrid polymersomes. A very high drug loading of camptothecin (100 μg/ml in the polymersome formulation) was reached and a drug release study of loaded magnetic polymersomes has shown a sustained camptothecin release over several days. Carboxylation of Pluronic ® L-121 was performed and enabled a further surface functionalization with bombesin, a 14 amino acid peptide, which bin…

PeptoSomes for Vaccination: Combining Antigen and Adjuvant in Polypept(o)ide-Based Polymersomes.

2017

In this work, the first vaccine is reported based on a PeptoSome, which contains a model antigen (SIINFEKL) and adjuvant (CpG). PeptoSomes are polypept(o)ide-based polymersomes built of a block-copolymer with polysarcosine (PSar) as the hydrophilic block (X n = 111) and poly(benzyl-glutamic acid) (PGlu(OBn)) as the hydrophobic one (X n = 46). The polypept(o)ide is obtained with low dispersity index of 1.32 by controlled ring-opening polymerization. Vesicle formation by dual centrifugation technique allows for loading of vesicles up to 40 mol%. PeptoSomes are characterized by multiangle dynamic light scattering, static light scattering, and cryogenic transmission electron microscopy (cryoTEM…

Techniques To Control Polymersome Size

2015

Polymersomes as synthetic analogues of liposomes appear frequently in relevant literature as promising candidates for a wide range of different applications including drug delivery, theranostic multitools, and nanoreactors. In particular, as nanotransporters for nanomedical applications in vivo, requirements concerning the reproducible manufacturing and reliable size control are extremely high. This Perspective highlights the importance of size control especially in the context of nanomedicine and gives an overview of the theoretical background of amphiphilic self-assembly leading to different preparation methods, where their feasibility of controlling polymersomes’ size is discussed.

Nanovesicles as Drug Delivery Vehicles: Liposomes and Polymersomes

2015

Rational design of ABC triblock terpolymer solution nanostructures with controlled patch morphology

2016

Block copolymers self-assemble into a variety of nanostructures that are relevant for science and technology. While the assembly of diblock copolymers is largely understood, predicting the solution assembly of triblock terpolymers remains challenging due to complex interplay of block/block and block/solvent interactions. Here we provide guidelines for the self-assembly of linear ABC triblock terpolymers into a large variety of multicompartment nanostructures with C corona and A/B cores. The ratio of block lengths NC/NA thereby controls micelle geometry to spheres, cylinders, bilayer sheets and vesicles. The insoluble blocks then microphase separate to core A and surface patch B, where NB co…

Viscoelasticity of pore-spanning polymer membranes derived from giant polymersomes

2010

We show how the viscoelastic properties of membranes formed from poly(butadiene)-block-poly(ethylene oxide) (PB130-b-PEO66) block copolymers can be locally accessed by atomic force microscopy. Polymer membranes are spread on microstructured porous silicon substrates from PB130-b-PEO66 vesicles by decreasing the osmotic pressure of the solution. Local viscoelastic properties of the pore-spanning polymer membranes were obtained from site-specific indentation experiments. Elastic moduli of these membranes were in the order of few MPa, while the elastic moduli of cross-linked membranes considerably increased to few GPa. Furthermore, the energy dissipation and velocity dependence of the hysteres…

Controlling Multicompartment Morphologies Using Solvent Conditions and Chemical Modification

2016

The solution self-assembly of amphiphilic diblock copolymers into spheres, cylinders, and vesicles (polymersomes) has been intensely studied over the past two decades, and their morphological behavior is well understood. Linear ABC triblock terpolymers with two insoluble blocks A/B, on the other hand, display a richer and more complex morphological spectrum that has been recently explored by synthetic block length variations. Here, we describe facile postpolymerization routes to tailor ABC triblock terpolymer solution morphologies by altering block solubility (solvent mixtures), blending with homopolymers, and block-selective chemical reactions. The feasibility of these processes is demonst…

Self-assembly of janus dendrimers into uniform dendrimersomes and other complex architectures

2010

Janus Drug Delivery Vehicle Efficient drug delivery vehicles need to be produced in a limited size range and with uniform size distribution. The self-assembly of traditional small-molecule and polymeric amphiphiles has led to the production of micelles, liposomes, polymeric micelles, and polymersomes for use in drug delivery applications. Now, Percec et al. (p. 1009 ) describe the self-assembly of Janus-type (i.e., two-headed) dendrimers to produce monodisperse supramolecular constructs, termed “dendrimersomes,” and other complex architectures. The structures, which showed long-term stability as well as very narrow size distributions, were easily produced by the injection of an ethanolic so…

Active surfaces engineered by immobilizing protein-polymer nanoreactors for selectively detecting sugar alcohols.

2016

We introduce active surfaces generated by immobilizing protein-polymer nanoreactors on a solid support for sensitive sugar alcohols detection. First, such selective nanoreactors were engineered in solution by simultaneous encapsulation of specific enzymes in copolymer polymersomes, and insertion of membrane proteins for selective conduct of sugar alcohols. Despite the artificial surroundings, and the thickness of the copolymer membrane, functionality of reconstituted Escherichia coli glycerol facilitator (GlpF) was preserved, and allowed selective diffusion of sugar alcohols to the inner cavity of the polymersome, where encapsulated ribitol dehydrogenase (RDH) enzymes served as biosensing e…