Bent out of shape: towards non‐spherical polymersome morphologies

Abstract

Polymersomes have gained a lot of attention in recent years. Their compartmentalized, hollow nature, stability and ability to transport both hydrophilic and hydrophobic cargo has made them attractive for increasingly complex applications in various fields of biomedicine, catalysis and diagnostics. Progress in these fields would therefore benefit from improvements in polymersome functionality. Recently, morphological control of polymersomes, namely the fabrication of various non-spherical morphologies, has emerged as a means to enhance the usefulness of the polymersomes. In the present review, we highlight the most topical trends in this field and how these developments and the newly acquired knowledge about their nature can be leveraged towards applications.

Light‐Triggered Unique Shape Transformation of Giant Polymersomes with Tubular Protrusions

“…The shape transformation of self‐assembled polymersomes requires additional forces to overcome bending energy and shift the system out of the thermodynamically stable or kinetically trapped shape. [ 3,17 ] As shown in Equation (), bending energy ( E b ) is determined by three parameters: the bending rigidity ( k ), the mean surface curvature ( C ), and the spontaneous curvature ( C 0 ). …”

Recent Progress in Phthalocyanine-Polymeric Nanoparticle Delivery Systems for Cancer Photodynamic Therapy

“…By tuning the ratio between the hydrophobic and hydrophilic units of amphiphilic block copolymers and adjusting the reaction conditions in an aqueous solution, distinct polymeric self-assembled structures can be achieved. The parameter which is responsible for the morphology of the self-assembled final product is ‘packing parameter’, p, which can be used to predict resulting self-assembled morphologies ( Scheme 2 A) [ 93 , 94 ]. It is defined as p = v/a o l c (v = the volume of the hydrophobic block, a o = the contact area of the head group, l c = the length of the hydrophobic block) [ 95 ].…”

“…It is defined as p = v/a o l c (v = the volume of the hydrophobic block, a o = the contact area of the head group, l c = the length of the hydrophobic block) [ 95 ]. As a general rule, a packing parameter lower than 1/3 creates spherical micelles, p between 1/2–1 results in polymersomes, and p in the range of 1/3–1/2 gives cylindrical micelles [ 93 , 94 , 95 , 96 ].…”

“…As mentioned above, either micelles or polymersomes can be formed depending on the ratio between the hydrophobic and hydrophilic units of copolymers [ 95 ]. For instance, Alibilandi et al [ 93 , 94 ] were able to prepare micelles using the PEG-PLA 5000:5000 copolymer. On the other hand, with PEG-PLA 5000:15,000 the hydrophobic PLA part was too bulky to fit in the corona of a micelle, thus the copolymer formed polymeric vesicles [ 93 , 94 ].…”

“…For instance, Alibilandi et al [ 93 , 94 ] were able to prepare micelles using the PEG-PLA 5000:5000 copolymer. On the other hand, with PEG-PLA 5000:15,000 the hydrophobic PLA part was too bulky to fit in the corona of a micelle, thus the copolymer formed polymeric vesicles [ 93 , 94 ].…”