Block copolymer self-assembly is normally conducted via post-polymerization processing at high dilution. In the case of block copolymer vesicles (or "polymersomes"), this approach normally leads to relatively broad size distributions, which is problematic for many potential applications. Herein we report the rational synthesis of low-polydispersity diblock copolymer vesicles in concentrated solution via polymerization-induced self-assembly using reversible addition-fragmentation chain transfer (RAFT) polymerization of benzyl methacrylate. Our strategy utilizes a binary mixture of a relatively long and a relatively short poly(methacrylic acid) stabilizer block, which become preferentially expressed at the outer and inner poly(benzyl methacrylate) membrane surface, respectively. Dynamic light scattering was utilized to construct phase diagrams to identify suitable conditions for the synthesis of relatively small, low-polydispersity vesicles. Small-angle X-ray scattering (SAXS) was used to verify that this binary mixture approach produced vesicles with significantly narrower size distributions compared to conventional vesicles prepared using a single (short) stabilizer block. Calculations performed using self-consistent mean field theory (SCMFT) account for the preferred self-assembled structures of the block copolymer binary mixtures and are in reasonable agreement with experiment. Finally, both SAXS and SCMFT indicate a significant degree of solvent plasticization for the membrane-forming poly(benzyl methacrylate) chains.

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A general protocol to synthesize superparamagnetic molecularly imprinted polymer particles, using a RAFT‐mediated approach, is described. S‐ propranolol‐imprinted composites were obtained by functionalizing commercially available amino‐modified Fe3O4 nanoparticles with a trithiocarbonate agent and subsequently by polymerizing thin molecularly imprinted layers. Different parameters were optimized and their effect on both nanomorphology and imprinting behaviour was studied. Optimum conditions allowed the synthesis of 40 nm composite particles with a 7 nm MIP shell, exhibiting superparamagnetic properties and specific molecular recognition of S‐ propranolol. The possibility of fine‐tuning the surface properties of the particles is demonstrated by using the “living” nature of active RAFT fragments present on the surface of the composites to further functionalize the particles with ethylene glycol methacrylate phosphate polymer brushes.

The field of molecularly imprinted polymer (MIP)-based chemosensors has been experiencing constant growth for several decades. Since the beginning, their continuous development has been driven by the need for simple devices with optimum selectivity for the detection of various compounds in fields such as medical diagnosis, environmental and industrial monitoring, food and toxicological analysis, and, more recently, the detection of traces of explosives or their precursors. This review presents an overview of the main research efforts made so far for the development of MIP-based chemosensors, critically discusses the pros and cons, and gives perspectives for further developments in this field.

RNA-based therapies offer aw ide range of therapeutic interventions including the treatment of skin diseases; however,the strategies to efficiently deliver these biomolecules are still limited due to obstacles related to the cellular uptake and cytoplasmic delivery.H erein, we report the synthesis of atriggerable polymeric nanoparticle (NP) library composed of 160 formulations,p resenting physico-chemical diversity and differential responsiveness to light. Six formulations were more efficient (up to 500 %) than commercially available lipofectamine in gene-knockdownactivity.These formulations showed differential internalization by skin cells and the endosomal escape was rapid (minutes range). The NPs were effective in the release of siRNAa nd miRNA. Acute skin wounds treated with the top hit NP complexed with miRNA-150-5p healed faster than wounds treated with scrambled miRNA. Lightactivatable NPs offer an ew strategy to topically deliver noncoding RNAs.

A sensitive electrochemical sensor was developed for the detection of nitro-explosives in aqueous solutions based on thin molecularly imprinted polydopamine films. Dopamine was identified in silico, based on DFT (density functional theory) calculations with the ωB97X-D/6-31G* basis set, as the best functional monomer and electropolymerized via cyclic voltammetry (CV) in the presence of carboxylic acid-based structural analogues ('dummy' templates) for two model nitro-explosives: TNT (2,4,6trinitrotoluene) and RDX (Research Department eXplosive, 1,3,5-trinitroperhydro-1,3,5-triazine). This approach afforded a homogenous coverage of gold electrodes with imprinted films of tunable thickness. The electropolymerized molecularly imprinted polydopamine films allowed for a 10 5-fold sensitivity improvement over a bare gold electrode based on tracking the redox peaks of the targets by CV. This improved sensitivity is ascribed to the ability of the MIP to concentrate its target in proximity to the transduction element. The MIP films showed reproducible binding in phosphate buffer (10 mM, pH 7.4), with a dynamic range from 0.1 nM to 10 nM for both TNT and RDX and an increased selectivity over closely related structural analogues.

Molecularly imprinted polymers (MIPs) are synthetic polymeric receptors, capable of specifically binding a target molecule, just like a biological antibody. There has been a recent trend to improve the properties of these materials by using modern methods of controlled radical polymerization (CRPs) for their synthesis. Despite the recognized advantages associated with their "living character", the effect of the "controlled nature" has still to be clearly demonstrated. This is far from obvious as the high amounts of short crosslinkers normally used for their synthesis complicate the formation of homogeneous polymer networks.In order to gain more insights into the potential benefits for the binding properties of MIPs resulting from the use of CRPs, the imprinting of a model target (S-propranolol) has been used to compare reversible addition-fragmentation chain transfer polymerisation (RAFT) and free-radical polymerisation (FRP) on acrylic and methacrylic matrices. While most MIPs are based on methacrylates, we used acrylates as a "difficult imprinting matrix" for comparison. In fact, the absence of the methyl groups in their polymer back-bone reduces their entanglement, resulting in a more flexible network. This renders the material more difficult to imprint, and at the same time makes it easier to evaluate the effects of RAFT polymerization and FRP on structural parameters and thus binding properties. Moreover, we also progressively reduced the amount of cross-linking in order to explore the effects of RAFT and FRP on a wider range of scaffold rigidities. Although MIPs are normally highly cross-linked, some recent emerging applications require lower degrees of cross-linking. Binding experiments, SEM, BET, DMA, swelling and nanoindentation analyses revealed that RAFT is effective in promoting the synthesis of more homogeneous networks compared to FRP, even at very high cross-linker contents, which results in higher target affinities, especially in the case of acrylates.

A new prospect for the synthesis of molecularly imprinted polymers: photo-iniferter polymerization under visible light.