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Interest in thermoresponsive polymers has steadily grown over many decades, and a great deal of work has been dedicated to developing temperature sensitive macromolecules that can be crafted into new smart materials. However, the overwhelming majority of previously reported temperature-responsive polymers are based on poly(N-isopropylacrylamide) (PNIPAM), despite the fact that a wide range of other thermoresponsive polymers have demonstrated similar promise for the preparation of adaptive materials. Herein, we aim to highlight recent results that involve thermoresponsive systems that have not yet been as fully considered. Many of these (co)polymers represent clear opportunities for advancements in emerging biomedical and materials fields due to their increased biocompatibility and tuneable response. By highlighting recent examples of newly developed thermoresponsive polymer systems, we hope to promote the development of new generations of smart materials.

Boronic acid-containing block copolymers capable of solution self-assembly into micelles and reverse micelles in response to changes in temperature, pH, and sugar concentration were prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization.

Novel sugar-responsive block copolymers were prepared by RAFT block copolymerization of unprotected boronic acid monomers, providing a direct route to supramolecular assemblies that dissociate upon the addition of glucose.

Simultaneous imaging of very early embryonic heart structure and function has technical limitations of spatial and temporal resolution. We have developed a gated technique using optical coherence tomography (OCT) that can rapidly image beating embryonic hearts in four-dimensions (4D), at high spatial resolution (10-15 mum), and with a depth penetration of 1.5 - 2.0 mm that is suitable for the study of early embryonic hearts. We acquired data from paced, excised, embryonic chicken and mouse hearts using gated sampling and employed image processing techniques to visualize the hearts in 4D and measure physiologic parameters such as cardiac volume, ejection fraction, and wall thickness. This technique is being developed to longitudinally investigate the physiology of intact embryonic hearts and events that lead to congenital heart defects.

Poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) was grafted from cellulose by reversible addition–fragmentation chain transfer (RAFT) polymerization. The use of a free chain transfer agent in solution allowed for a better control over graft ratio, chain length of grafted polymer, monomer conversion, and homopolymer formation in solution. An increase in polymerization time or degree of polymerization led to an increase in graft ratio, as expected from a living system.

Background The surface modification of the cellulose fibres through graft polymerization is of great interest to the researcher due to their wide range of potential applications. Living radical polymerization methods have been used to achieve well defined and living polymer grafts from the cellulose surface. [1] RAFT polymerization is a versatile method that allows the synthesis of polymers with complex molecular architectures, low polydispersity, and functionalizable end groups. [2] The controlled surface modification of different solid substrates (such as poly(propylene) lanterns, core-shell microspheres, silica, gold nanoparticles, carbon nanotubes, and the Merrifield resin system) via RAFT has already been reported. [3-7] RAFT graft polymerization from a solid support can be performed using both the R-group approach (the leaving and reinitiating R-group attached to the backbone) and the Z-group approach (the stabilizing group attached to the backbone).The R-group approach follows the 'grafting from' mechanism and higher graft densities can be achieved relative to that achieved using the 'grafting onto' (Z-group) approach due to fewer steric hindrance problems. [7,8] The use of a solid-supported chain transfer agent (the R-group approach) to mediate the controlled graft polymerization from the different cellulosic surfaces such as cotton fabric and filter paper has been the focus of recent studies. [9-11] Current research into RAFT polymerization is covered by two reviews. [12,13] .

Key immunogenic and immunomodulatory molecules after 3 days of in vitro treatment of ucMSC. The table displays the mean ± SEM percentages of MSC expressing surface markers HLA class –I and –II, PD-L1 and CD73, measured via flow cytometric analysis. Mean ± SEM concentration of L-Kynurenine [µM] and PGE2 [ng/ml]. Fold increase of IL1RA gene expression compared to unstimulated ucMSC. n=5, no significant differences were observed. (DOCX 17 kb)

Key immunogenic and immunomodulatory molecules after 3 days of in vitro treatment of ucMSC. The table displays the mean ± SEM percentages of MSC expressing surface markers HLA class –I and –II, PD-L1 and CD73, measured via flow cytometric analysis. Mean ± SEM concentration of L-Kynurenine [µM] and PGE2 [ng/ml]. Fold increase of IL1RA gene expression compared to unstimulated ucMSC. n=5, no significant differences were observed. (DOCX 17 kb)