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Polymerization‐induced self‐assembly (PISA) with (in situ) encapsulation of (therapeutic) cargo has proven to be an efficient preparation method for loaded polymeric micelles and polymersomes, thereby presenting significant opportunities in the field of drug delivery. However, despite extensive research efforts, no significant advances toward systematic in vivo studies or clinical applications have been achieved to date. In this Review, we outline the current state‐of‐the‐art of cargo encapsulation via PISA with a specific focus on developments achieved in the past 5 years. Considering the general requirements for functional drug delivery systems, we identify the major hurdles that still need to be overcome in order to push PISA‐derived systems from a promising academic exercise to viable candidates for clinical translation. [ABSTRACT FROM AUTHOR]

The influence of homopolymer architecture on the properties of polyion complex micelles is reported. Using a combination of dynamic and static light scattering, the authors show how the architecture is only relevant in kinetically trapped states of micelles formed by the electrostatic assembly of poly(N‐isopropyl acrylamide‐block‐styrene sulfonate) (p(NIPAM‐b‐SS) and linear, 4‐arm, 8‐arm star quaternized poly(dimethyl amino ethyl acrylate) (PDMAEA) homopolymers or poly(amidoamine) (PAMAM) dendrimers. Interestingly, the micellar size and the aggregation number in these kinetically arrested states follow a clear trend with the number of arms but differ in the case of dendrimers possibly due to the distinct chemical nature of the monomers. The authors show that if the micelles are prepared in a weak polyelectrolyte pairing regime (i.e., high ionic strength), they all converge into similar structures. The presented findings represent a new way of controlling the properties of polyion complex micelles through kinetically trapped states. [ABSTRACT FROM AUTHOR]

We report a switchable, templated polymerization system where the strength of the templating effect can be modulated by solution pH and/or ionic strength. The responsiveness to these cues is incorporated through a dendritic polyamidoamine‐based template of which the charge density depends on pH. The dendrimers act as a template for the polymerization of an oppositely charged monomer, namely sodium styrene sulfonate. We show that the rate of polymerization and maximum achievable monomer conversion are directly related to the charge density of the template, and hence the environmental pH. The polymerization could effectively be switched "ON" and "OFF" on demand, by cycling between acidic and alkaline reaction environments. These findings break ground for a novel concept, namely harnessing co‐assembly of a template and growing polymer chains with tunable association strength to create and control coupled polymerization and self‐assembly pathways of (charged) macromolecular building blocks. [ABSTRACT FROM AUTHOR]

We report a switchable, templated polymerization system where the strength of the templating effect can be modulated by solution pH and/or ionic strength. The responsiveness to these cues is incorporated through a dendritic polyamidoamine‐based template of which the charge density depends on pH. The dendrimers act as a template for the polymerization of an oppositely charged monomer, namely sodium styrene sulfonate. We show that the rate of polymerization and maximum achievable monomer conversion are directly related to the charge density of the template, and hence the environmental pH. The polymerization could effectively be switched "ON" and "OFF" on demand, by cycling between acidic and alkaline reaction environments. These findings break ground for a novel concept, namely harnessing co‐assembly of a template and growing polymer chains with tunable association strength to create and control coupled polymerization and self‐assembly pathways of (charged) macromolecular building blocks. [ABSTRACT FROM AUTHOR]

We report the (spontaneous) formation of colloidal strings, Bernal spiral-like, and tubular clusters comprising spherical, isotropically functionalized colloidal particles in an aqueous environment. The formation of colloidal strings and Bernal spiral-like clusters is guided by an interplay between short-ranged hydrophobic attraction and relatively longer-ranged electrostatic repulsion acting between the colloids. When a dispersion of these colloids is densified via centrifugation, well-defined tubular aggregates were observed. [ABSTRACT FROM AUTHOR]

In this paper, we report a new synthetic procedure to immobilize a transfer hydrogenation catalyst on the surface of colloidal polystyrene particles. Using supports of colloidal dimensions allows for combining a relatively high surface area for catalyst binding, mobility of the catalyst, and facile recovery by centrifugation or sedimentation. The immobilization procedure relies on the covalent attachment of terpyridine moieties on the particle surface. These immobilized terpyridines are subsequently employed as colloidal ligands, which participate in the formation of an active ruthenium-based transfer hydrogenation catalyst. The resulting functional colloidal particles successfully catalyze the transfer hydrogenation of acetophenone with 2-propanol as the hydrogen donor. Thorough analysis of the chemical composition of the colloidal surface led to the determination of the catalyst loading per particle. This enabled us to conduct reference hydrogenations with equal concentrations of the homogeneous transfer hydrogenation catalyst to probe the effect of the immobilization procedure on the catalytic activity. Despite a decrease in transfer hydrogenation activity, full acetophenone conversion is still achievable within 24 h. Preliminary experiments show that the catalytic colloids are recyclable without significant loss of transfer hydrogenation activity. [ABSTRACT FROM AUTHOR]

B Polymerisationen b Philipp Gerdt und Armido Studer berichten in ihrem Forschungsartikel (e202206964) über eine Methode für die Synthese von funktionalisierten alternierenden Copolymeren durch radikalische Polymerisation mit reversibler Deaktivierung. Keywords: Complex Core Coacervate Micelles; PIESA; Polyelectrolytes; RAFT Polymerization; Templated Polymerizations EN Complex Core Coacervate Micelles PIESA Polyelectrolytes RAFT Polymerization Templated Polymerizations 1 1 1 09/21/22 20220926 NES 220926 B Schaltbare templatierte Polymerisationen b werden von Bas G. P. van Ravensteijn, Ilja K. Voets et al. in ihrem Forschungsartikel vorgestellt (e202206780). Complex Core Coacervate Micelles, PIESA, Polyelectrolytes, RAFT Polymerization, Templated Polymerizations. [Extracted from the article]

Keywords: Complex Core Coacervate Micelles; PIESA; Polyelectrolytes; RAFT Polymerization; Templated Polymerizations EN Complex Core Coacervate Micelles PIESA Polyelectrolytes RAFT Polymerization Templated Polymerizations 1 1 1 09/21/22 20220926 NES 220926 B Switchable templated polymerization b is reported by Bas G. P. van Ravensteijn, Ilja K. Voets et al. in their Research Article (e202206780), as illustrated in the cover picture. Cover Picture: Switchable Electrostatically Templated Polymerization (Angew. Complex Core Coacervate Micelles, PIESA, Polyelectrolytes, RAFT Polymerization, Templated Polymerizations. [Extracted from the article]