We report the synthesis of highly transparent poly(stearyl methacrylate)-poly(2,2,2-trifluoroethyl methacrylate) (PSMA–PTFEMA) diblock copolymer nanoparticles via polymerization-induced self-assembly (PISA) in nonpolar media at 70 °C. This was achieved by chain-extending a PSMA precursor block via reversible addition–fragmentation chain transfer (RAFT) dispersion polymerization of TFEMA in n-tetradecane. This n-alkane has the same refractive index as the PTFEMA core-forming block at 70 °C, which ensures high light transmittance when targeting 33 nm spherical nanoparticles. Such isorefractivity enables visible absorption spectra to be recorded with minimal light scattering even at 30% w/w solids. However, in situ monitoring of the trithiocarbonate RAFT end-groups during PISA requires selection of a weak n → π* band at 446 nm. Conversion of TFEMA into PTFEMA causes a contraction in the reaction solution volume, leading to an initial increase in absorbance that enables the kinetics of polymerization to be monitored via dilatometry. At ∼98% TFEMA conversion, this 446 nm band remains constant for 2 h at 70 °C, indicating surprisingly high RAFT chain-end fidelity (and hence pseudoliving character) under monomer-starved conditions. In situ 19F NMR spectroscopy studies provide evidence for (i) the onset of micellar nucleation, (ii) solvation of the nanoparticle cores by TFEMA monomer, and (iii) surface plasticization of the nanoparticle cores by n-tetradecane at 70 °C. Finally, the kinetics of RAFT chain-end removal can be conveniently monitored by in situ visible absorption spectroscopy: addition of excess initiator at 70 °C causes complete discoloration of the dispersion, with small-angle X-ray scattering studies confirming no change in nanoparticle morphology under these conditions.

A novel series of HDAC inhibitors demonstrating class I subtype selectivity and good oral bioavailability is described. The compounds are potent enzyme inhibitors (IC₅₀ values less than 100 nM), and improved activity in cell proliferation assays was achieved by modulation of polar surface area (PSA) through the introduction of novel linking groups. Employing oral pharmacokinetic studies in mice, comparing drug levels in spleen to plasma, we selected compounds that were tested for efficacy in human tumor xenograft studies based on their potential to distribute into tumor. One compound, 21r (CHR-3996), showed good oral activity in these models, including dose-related activity in a LoVo xenograft. In addition 21r showed good activity in combination with other anticancer agents in in vitro studies. On the basis of these results, 21r was nominated for clinical development.

Time-resolved small-angle neutron scattering studies confirm that copolymer chain exchange occurs between sterically-stabilized diblock copolymer nanoparticles at elevated temperature.

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The development of stable perovskite precursor solutions is critical if solution‐processable perovskite solar cells (PSCs) are to be practically manufacturable. Ideally, such precursors should combine high solution stability without using chemical additives that might compromise PSC performance. Here, it was shown that the shelf‐life of high‐performing perovskite precursors could be greatly improved by storing solutions at low‐temperature without the need to alter chemical composition. Devices fabricated from solutions stored for 31 days at 4 °C achieved a champion power conversion efficiency (PCE) of 18.6 % (97 % of original PCE). The choice of precursor solvent also impacted solution shelf‐life, with DMSO‐based solutions having enhanced solution stability compared to those including DMF. The compositions of aged precursors were explored using NMR spectroscopy, and films made from these solutions were analysed using X‐ray diffraction. It was concluded that the improvement in precursor solution stability is directly linked to the suppression of an addition‐elimination reaction and the preservation of higher amounts of methylammonium within solution.