Controlling responsive emulsion properties via polymer design.

Subtle changes in copolymer surfactant architecture and chain-end functionality can induce diverse behaviours in pH-responsive branched copolymer-stabilized emulsions.

Medicines reconciliation at the community mental health team-general practice interface: quality improvement study.

Aims and methodTo increase the proportion of patients with no psychotropic drug discrepancies at the community mental health team (CMHT)-general practice interface. Three CMHTs participated. Over a 14 month period, quality improvement methodologies were used: individual patient-level feedback to patient's prescribers, run charts and meetings with CMHTs. RESULTS: One CMHT improved medicines reconciliation accuracy and demonstrated significant reductions in prescribing discrepancies. One in three (119/356) patients had ≥1 discrepancy involving 20% (166/847) of all prescribed psychotropics. Discrepancies were graded as: 'fatal' (0%), 'serious' (17%) and 'negligible/minor harm' (83%) but were associated with extra avoidable prescribing costs. For medicines routinely supplied by secondary care, 68% were not recorded in general practice electronic prescribing systems.Clinical implicationsImprovements in medicines reconciliation accuracy were achieved for one CMHT. This may have been partly owing to a multidisciplinary team approach to sharing and addressing prescribing discrepancies. Improving prescribing accuracy may help to reduce avoidable drug-related harms to patients.Declaration of interestNone.

pH-Responsive branched polymernanoparticles.

We describe a new one-pot, single-step route for the preparation of pH-responsive branched polymer nanoparticles. These polymers, which are based on the pH-responsive monomer 2-(diethylamino)ethyl methacrylate (DEA) and hydrophilic macromonomer poly(ethyleneglycol) methacrylate (PEGMA), are synthesised using a modified conventional free-radical polymerisation. Consequently, their preparation is generic, scaleable and tolerant of functionality. In aqueous solution the branched copolymers form core-shell structures at basic pH and on reducing the solution pH they become hydrated and swell, displaying similar characteristics to those of pH-responsive shell cross-linked micelles and microgels. We demonstrate good control over the hydrodynamic particle size, polymer chain-end, and the uptake and release of a model hydrophobe and also the ability to tune the apparent pKa of the DEA residues by varying the degree of branching. These results augur well for commercially viable tunable release applications.

One-pot, single-component synthesis of functional emulsion-templated hybrid inorganic-organic polymer capsules.

Multi-purpose amphiphilic branched copolymer surfactants can be used to simultaneously stabilise and cross-link emulsion droplets to produce encapsulated spheres and hollow capsules.

Synthesis and characterization of shell cross-linked micelles with hydroxy-functional coronas: a pragmatic alternative to dendrimers?

Shell cross-linked (SCL) micelles with hydroxy-functional coronas have been constructed in aqueous solution by exploiting the micellar self-assembly behavior of a new thermoresponsive ABC triblock copolymer. This copolymer was prepared via atom transfer radical polymerization in a convenient one-pot synthesis and comprised a thermoresponsive core-forming poly(propylene oxide) (PPO) block, a cross-linkable central poly(2-(dimethylamino)ethyl methacrylate) (DMA) block, and a hydroxy-functional outer block based on poly(glycerol monomethacrylate) (GMA). DMF GPC analysis confirmed a unimodal molecular weight distribution for the PPO-PDMA-PGMA triblock copolymer precursor, with an M(n) of 12 100 and a polydispersity of approximately 1.26. This copolymer dissolved molecularly in aqueous solution at 5 degrees C but formed micelles with hydroxy-functional coronas above a critical micelle temperature of around 12 degrees C, which corresponded closely to the cloud point of the PPO macroinitiator. Cross-linking of the DMA residues using 1,2-bis(2-iodoethoxy)ethane produced SCL micelles that remained intact at 5 degrees C, i.e., below the cloud point of the core-forming PPO block. Dynamic light scattering studies confirmed that the SCL micelle diameter could be varied depending on the temperature employed for cross-linking: smaller, more compact SCL micelles were formed at higher temperatures, as expected. Since cross-linking involved quaternization of the DMA residues, the SCL micelles acquired cationic surface charge as judged by aqueous electrophoresis studies. These cationic SCL micelles were adsorbed onto near-monodisperse anionic silica sols, which were used as a model colloidal substrate. Thermogravimetric analyses indicated a SCL micelle mass loading of 2.5-4.4%, depending on the silica sol diameter and the initial micelle concentration. Aqueous electrophoresis measurements confirmed that surface charge reversal occurred after adsorption of the SCL micelles, and scanning electron microscopy studies revealed a uniform coating of SCL micelles on the silica particles.