Macromolecular engineering to the service of advanced drug delivery systems

Conference (2010, October 25)

Multilayered chitosan-based nanofibers with antibacterial properties

Poster (2010, October 14)

Towards the synthesis of mannose derivatives of natural phenolic compounds

Poster (2010, October 14)

The aim of this project is to graft a sugar moiety onto polyfunctional natural phenolic compounds. This should enhance their water solubility. The choice of an adequate sugar such as mannose could provide ... [more ▼]

The aim of this project is to graft a sugar moiety onto polyfunctional natural phenolic compounds. This should enhance their water solubility. The choice of an adequate sugar such as mannose could provide cellular recognition. The synthesis route was first tested on cinnamyl alcohol which is structurally close to the base pattern of natural phenolic compounds. Two compounds are tested to catalyse the glycosilation between cinnamyl alcohol and D-mannose. The first one is an enzyme, the -glucosidase from almond, and the second one is a mineral acid catalyst immobilized on silica. Results show that -glucosidase is able to synthetize cinnamyl mannoside from mannose and cinnamyl alcohol. Furthermore, enzyme-catalyzed route lead to only one product and is so more specific than the chemical route where several products are observed. The obtaining of one product with a unique structure is interesting for the fundamental study of structure-function relationships (Interaction of the product with model membranes by Isothermal Titration Calorymetry and with the Langmuir Trough technique). In a future work, the reaction will be tested with more complex molecules (for example coniferyl alcohol). [less ▲]

Extrusion foaming of poly(styrene-co-acrylonitrile)/ clay nanocomposites using supercritical CO2

in Macromolecular Materials and Engineering (2010), 295(10), 915-

Supercritical CO2 has been used as a blowing agent to foam poly(styrene-co-acrylonitrile)-based materials in a single screw extruder specially adapted to allow fluid injection. The cellular morphology ... [more ▼]

Supercritical CO2 has been used as a blowing agent to foam poly(styrene-co-acrylonitrile)-based materials in a single screw extruder specially adapted to allow fluid injection. The cellular morphology depends on foaming temperature, more regular cells being obtained with decreasing extrusion temperature. In a second step, a natural and an organomodified nanoclay have been added for the purpose of imparting some flame resistance to the foamed material. The filler efficiency in reducing sample combustion rate appeared to be dependent on its delamination level inside the matrix and better results were obtained when the organomodified clay was first delaminated in the polymer in an efficient twin screw extruder using water assistance, prior to foaming in the single screw extruder. [less ▲]

Macromolecular engineering to the service of advanced drug delivery systems

Conference (2010, September 16)

Tailor-made copolymers for responsive drug delivery nanosystems

Poster (2010, September 15)

Synthesis of new responsive biodegradable polymer for advanced drug delivery systems

Conference (2010, September 07)

pH-sensitive micellar systems for controlled drug delivery: synthesis and structural characterization by small-angle neutron scattering

Poster (2010, September 07)

Enzymatic synthesis of novel carbohydrate surfactants for water/supercritical CO2 emulsions

Poster (2010, September 07)

Polymers in modern ophthalmic implants—Historical background and recent advances

in Materials Science & Engineering : R (2010), 69(6), 63-83

Cataract surgery is the most frequently performed surgical intervention, pursued by replacement of the opacified natural lens by a polymeric intraocular lens (IOL). This paper, based on an exhaustive ... [more ▼]

Cataract surgery is the most frequently performed surgical intervention, pursued by replacement of the opacified natural lens by a polymeric intraocular lens (IOL). This paper, based on an exhaustive number of scientific references, provides a brief simplified discussion of the surgical advances for cataract treatment, and is mainly focused on the process of IOL discovery, engineering and development. The performances of the polymer materials, used for the IOLs fabrication are discussed in a comparative way, and their properties, such as handling during surgery, biocompatibility, rate of some post-surgical complications (e.g. Posterior Capsular Opacification) and optical properties, are considered. Special attention is paid on the basic scientific approaches for engineering and modification of the IOL surface and bulk properties. Polymer coating techniques like ‘grafting onto’ and ‘grafting from’ are discussed and exemplified by a variety of coating compositions and performances. In another part of the review, modification techniques concerning optimization of the bulk properties of the polymer lens are also discussed and synthetic approaches such as copolymerization and nanocomposite formation are considered. A perspective aspect of this discussion concerns improvement of the performance of the main polymer by the incorporation of in situ formed or preformed nanoparticles. The most attractive perspectives concerning the improvement of the IOL properties by chemical modification approaches are described. [less ▲]