Giant Biodegradable Poly(ethylene glycol)‐block‐Poly(ε‐caprolactone) Polymersomes by Electroformation

Abstract

Here, the formation of giant enzyme‐degradable polymersomes using the electroformation method is reported. Poly(ethylene glycol)‐block‐poly(ε‐caprolactone) polymersomes have been shown previously to be attractive candidates for the detection of bacterial proteases and protease mediated release of encapsulated reporter dyes and antimicrobials. To maximize the efficiency, the maximization of block copolymer (BCP) vesicle size without compromising their properties is of prime importance. Thus, the physical‐chemical properties of the BCP necessary to self‐assemble into polymeric vesicles by electroformation are first identified. Subsequently, the morphology of the self‐assembled structures is extensively characterized by different microscopy techniques. The vesicular structures are visualized for giant polymersomes by confocal laser scanning microscopy upon incorporation of reporter dyes during the self‐assembly process. Using time correlated single photon counting and by analyzing the fluorescence decay curves, the nanoenvironment of the encapsulated fluorophores is unveiled. Using this approach, the hollow core structure of the polymersomes is confirmed. Finally, the encapsulation of different dyes added during the electroformation process is studied. The results underline the potential of this approach for obtaining microcapsules for subsequent triggered release of signaling fluorophores or antimicrobially active cargo molecules that can be used for bacterial infection diagnostics and/or treatment.

Light-Triggered Polymersome-Based Anticancer Therapeutics Delivery

“…Thus, polymersome self-assemblies may be degradable or non-degradable, depending on the selected monomers [ 125 ]. While degradable monomers include structures from aliphatic polyesters and polycarbonates, such as PEG [ 126 ], poly(lactic acid) (PLA) [ 127 ], polycaprolactone (PCL) [ 128 ], and poly(trimethylene carbonate) (PTMC) [ 129 ], non-degradable ones include conjugated or aromatic hydrocarbon blocks, such as poly(ethyl ethylene) (PEE) [ 78 ], poly(butadiene) (PBD) [ 130 ], and PS [ 131 ], among others [ 70 ]. Independent of the monomer degradability, the hydrophobic and hydrophilic amphiphilic organizations formed by their self-assembly constitute the bilayer of the polymersomes, defining their thickness, stability, and permeability.…”

Polymer Capsules with Hydrophobic Liquid Cores as Functional Nanocarriers

“…Considering that many substances of interest exhibit limited solubility in water, several attempts have been proposed to encapsulate such compounds, deliver them effectively, and release in a controlled manner at the site of action. Colloidal particles such as dendrimers, micelles, capsules, liposomes and polymersomes exhibit adequate size, high loading capacity, and sufficient stability which make them frequently used in the mentioned applications [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. However, several aspects need to be considered during the design and development of such carriers.…”

Macromolecular design and preparation of polymersomes

“…As a result, the degree of bulging and separation of the vesicles can be controlled to give a narrow distribution of polymersome sizes. 95,96…”