Recent advances and prospects in nano drug delivery systems using lipopolyoxazolines

International audienc

Towards N-rich solid polymer electrolytes for Li-ion batteries?

Solid polymer electrolytes (SPEs) are faced with many specifications to replace today's liquid organic electrolyte in Li-ion batteries, here BPEI based polymer is proposed as a new SPE

Light-Switchable Nanoparticles Based on Amphiphilic Diblock, Triblock and Heterograft Polyoxazoline

International audiencePhoto-active nanoparticles (NPD, NPT, NPH) were elaborated in water from amphiphilic diblock (D), triblock (T) and heterograft (H) copolymers based on a chromatic unit, coumarin, linked to an alkyl chain and a hydrophilic polyoxazoline chain. Under UV-exposure, for graft copolymers, the coumarin moieties crosslink the nanoparticle core (NPHx) while a simple dimerization chain by chain happens with linear diblock and triblock copolymers (NPDx and NPT). The self-assembly of these copolymers was examined as well as the UV-activity and UV-reversibility of the corresponding NPs by UV spectroscopy. Their stability under light exposure and temperature was also monitored by dynamic light scattering (DLS). Finally, the loading of a lipophilic fluorescent probe (Nile Red) into the NP core was evaluated by fluorescence emission. All these data illustrate the tunable size, UV-activity, stability and loading efficiency of the NPs by the starting macromolecular architecture of the amphiphilic copolymers. Triblock copolymers seem to be a promising tool for switchable NPs characterized by two opposite states: NPs with and without photo-dimerized core alternatively

Amphiphilic copolymers based on polyoxazoline and grape seed vegetable oil derivatives: self-assemblies and dynamic light scattering

International audienc

Polyoxazolines based lipid nanocapsules for topical delivery of antioxidants

International audienceNano-sized lipid formulations offer a great potential for topical delivery of active compounds to treat and prevent human skin damages. Of particular importance is the high loading of hydrophobic molecules, the long-term stability and the auspicious penetration capacity especially reached when using lipid nanocapsules (LNC). Unfortunately, their formation currently relies on a phase inversion process that only operates when using a poly(ethylene glycol) (PEG) based surfactant belonging to the controversial PEG family that was subject of clinical awareness. The present study proposes an alternative to this overused polymer in formulations by designing LNC made of harmless amphiphilic polyoxazolines (POx). Implementing a short sonication step in the process allowed well-defined spherical nanoparticles of ~30 nm to be obtained. The structure of the so called LNC POx was composed of an oily core surrounded by a rigid shell of phospholipids and POx, which ensures a high stability over time, temperature, centrifugation and freezing. Encapsulation of the natural quercetin antioxidant led to a drug loading three times higher than for LNC constituted of PEG (LNC PEG). The antioxidant activity of loaded LNC POx was tested on mice fibroblasts and human keratinocytes after exposure to free radicals from peroxides and UVB irradiation, respectively. The radical scavenging capacity of quercetin loaded in the LNC POx was preserved and even slightly enhanced compared to LNC PEG, highlighting the POx value in nanoformulations

Polyoxazolines based mixed micelles as PEG free formulations for an effective quercetin antioxidant topical delivery

International audienc

New Hunter River Hotel card 3 side 1

The Noel Butlin Archives Centre also holds property and manager files for this hotel