Miniemulsion polymerization

Design and production of nanoparticles formulated from nano-emulsion templates-a review

A considerable number of nanoparticle formulation methods are based on nano-emulsion templates, which in turn are generated in various ways. It must therefore be taken into account that active principles and drugs encapsulated in nanoparticles can potentially be affected by these nano-emulsion formulation processes. Such potential differences may include drug sensitivity to temperature, high-shear devices, or even contact with organic solvents. Likewise, nano-emulsion formulation processes must be chosen in function of the selected therapeutic goals of the nano-carrier suspension and its administration route. This requires the nanoparticle formulation processes (and thus the nano-emulsion formation methods) to be more adapted to the nature of the encapsulated drugs, as well as to the chosen route of administration. Offering a comprehensive review, this paper proposes a link between nano-emulsion formulation methods and nanoparticle generation, while at the same time bearing in mind the above-mentioned parameters for active molecule encapsulation. The first part will deal with the nano-emulsion template through the different formulation methods, i.e. high energy methods on the one hand, and low-energy ones (essentially spontaneous emulsification and the phase inversion temperature (PIT) method) on the other. This will be followed by a review of the different families of nanoparticles (i.e. polymeric or lipid nanospheres and nanocapsules) highlighting the links (or potential links) between these nanoparticles and the different nano-emulsion formulation methods upon which they are based.

RAFT mediated polymerisation in heterogeneous media

Reversible addition fragmentation chain transfer (RAFT) mediated polymerisation is one of a number of living radical polymerisation processes that were developed over the last decade. The RAFT process is facilitating the synthesis of controlled macromolecular architectures radical polymerisation in homogeneous and heterogeneous media. Here we discuss the progress in the use of the RAFT process, the past, the state of the art and potential directions for the future with specific emphasis on heterogeneous reactions.

High-performance fluorescent particles prepared via miniemulsion polymerization

Highly fluorescent polymer particles were prepared with Eu beta-diketonates complex as a fluorophore by miniemulsion polymerization technique. Eu beta-diketonates complex has a long decay time, a large Stokes shift, and very narrow emission bands in comparison with other organic fluorescent compounds. Aqueous miniemulsion was prepared by mixing monomer, crosslinker, hydrophobe, and Eu beta-diketonates complex and then putting the mixture into an aqueous solution of surfactant, followed by ultrasonication. An aqueous solution of initiator was added to the miniemulsion to obtain fluorescent polymer particles, which were monodispersed without aggregation. Particle size was decreased to deca-nano scale by increasing the amount of surfactant. Fluorescent intensity was increased by using Eu beta-complex coordinated with additional ligand. Further fluorescence quantum yields and fluorescent properties in the presence of DNA were investigated to the confirm superiority of Eu beta-diketonates complexes in polymer particles.