Publications

The invention describes a method for isolating one or more genetic elements encoding a gene product having a desired activity, comprising the steps of: (a) compartmentalising genetic elements into microcapsules; and (b) sorting the genetic elements which express the gene product having the desired activity; wherein at least one step is under microfluidic control. The invention enables the in vitro evolution of nucleic acids and proteins by repeated mutagenesis and iterative applications of the method of the invention.

The invention describes a method for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, comprising the steps of: a) compartmentalising the compounds into microcapsules together with the target, such that only a subset of the repertoire is represented in multiple copies in any one microcapsule; and b) identifying the compound which binds to or modulates the activity of the target; wherein at least one step is performed under microfluidic control. The invention enables the screening of large repertoires of molecules which can serve as leads for drug development.

A composition comprising in a continuous aqueous phase a monodisperse lipid phase comprising one or more crystallizable lipids, one or more active principles and a least one dispersed phase stabilizing compound comprising two fatty acid chains and a polyethylene glycol chain, is new. - Independent claims are included for a methods of preparing the claimed composition by: - (a) introducing the active principle(s) into the crystallizable lipid; - (b) dispersing the lipid phase in the aqueous phase in the presence of an emulsifier to form an emulsion; - (c) subjecting the emulsion to shear to form a monodisperse emulsion or where the lipid phase comprises an internal aqueous phase, by: - (i) dispersing an aqueous solution comprising the active principles into the lipid (which may contain one or more active principles) in a melted state in the presence of a lipophilic surfactant; - (ii) subjecting the emulsion obtained to shear to render it monodisperse; - (iii) incorporating the monodisperse emulsion in an aqueous phase in the presence of a stabilizer to form a double emulsion; and - (iv) subjecting the double emulsion to shear to produce a monodisperse double emulsion

Producing monodisperse biodegradable microspheres (I), comprising preparing an emulsion comprising at least one polymer phase containing an active agent (A) and at least one aqueous phase, the ratio of viscosities of the organic and aqueous phases being 0.1-10, subjecting the emulsion to controlled laminar shear, removing the solvent from the polymer phase, and recovering the obtained microspheres, is new.

Assembling colloidal particles in the form of irreversibly organized chains bearing species-recognition sites different from the ligands involved in organizing the particles, is new. Independent claims are also included for: (1) producing an assembly by assembling colloidal particles in the form of linear objects and contacting the objects with an agent capable of bridging them irreversibly; (2) producing an assembly by mixing and/or grafting colloidal particles with a bridging agent or bridging agent precursor, assembling the particles in the form of linear objects, and initiating bridging between the particles; (3) detecting, analysis, purification, identification, separation or ex-vivo monitoring of at least one species using an assembly; (4) a surface element bearing an assembly; (5) a hybridization array comprising the surface element of (4); (6) a microfluidic channel or cell comprising an assembly.

Detecting and/or quantifying (M1) at least one analyte (A) in a liquid comprising using colloidal magnetic particles (B), functionalized on the surface with at least one ligand (L) specific for (A), is new. M1 comprises: (a) combining test sample and (B); (b) applying a magnetic field strong enough to structure (B) as chains; (c) maintaining the field for long enough to allow coupling/association of (I) with at least two (L), present on two adjacent particles in the chain; (d) turning of the field; and (e) detecting presence/absence of (I), and optionally its concentration, from the presence/absence of permanent chains of (B). An Independent claim is also included for a reagent kit containing (B).

Food emulsion comprising a primary water-in-oil emulsion dispersed in an aqueous phase is stabilized with a natural lipophilic surfactant system present in the primary emulsion. An Independent claim is also included for a process for producing the emulsion by dispersing an internal aqueous phase in an oil phase containing the surfactant system and dispersing the resulting water-in-oil emulsion in an external aqueous phase.

The invention concerns a method for the controlled release of an active principle contained in a multiple water-in-oil-in-water emulsion characterised in that: said multiple emulsion comprises an invert emulsion Ei with a aqueous phase A1 containing at least a hydrophilic active principle, said emulsion Ei being dispersed in the form of direct emulsion droplets Ed, in a continuous aqueous phase A2, with the two emulsions Ed and Ei stabilised by at least a surfactant, present in their respective continuous phases; and said multiple emulsion is brought in the presence of an effective amount of an agent for transforming it into a direct emulsion and induce the release of the active principle, contained in the aqueous phase A1 of emulsion Ei, in the aqueous phase A2.

The invention concerns composite nanospheres having a diameter ranging between about 50 and 1000 nm plus or minus 5%, preferably between about 100 and 500 nm plus or minus 5% and advantageously between 100 and 200 nm plus or minus 5%, and comprising an essentially liquid core consisting of an organic phase and inorganic nanoparticles, distributed inside the organic phase, and a skin consisting of at least a hydrophilic polymer derived from the polymerisation of at least one water soluble monomer, in particular N-alkylacrylamide or a N-N-dialkylacrylamide; conjugates derived from said nanospheres; their preparation methods and their uses.

The invention concerns composite particles comprising a hydrophobic polymer and inorganic nanoparticles, said particles having a diameter of about 50 to 1000 nm, preferably about 100 to 500 nm, and advantageously from about 100 to 250 nm and comprising a hydrophobic polymer consisting of a polymer matrix and the inorganic nanoparticles stabilised and distributed relative homogeneously inside said matrix. The invention also concerns conjugates derived from said composite particles, their method of preparation and their uses.

The invention concerns a fractionable polydisperse stable double oil-in-water emulsion, consisting of 50 to 95 wt.%, relative to the total weight of the double emulsion, droplets of an invert monodisperse emulsion Ei dispersed in a continuous aqueous phase; the continuous aqueous phase comprising a polysaccharide thickening agent in a proportion of 1 to 10 wt.% relative to the total weight of the continuous aqueous phase; a water-soluble ethylene oxide and propylene oxide block copolymer as surfactant; and an osmotic pressure balancing agent; the emulsion Ei having a viscosity not higher than the viscosity of the continuous aqueous phase and consisting of 50 to 95 wt.%, relative to the total weight of Ei, droplets of an internal aqueous phase dispersed in an oily phase; the internal aqueous phase comprising at least an active hydrophilic substance; the oily phase comprising polyglycerol polyricinoleate as surfactant. The invention further concerns the corresponding monodisperse double emulsion of the same formulation and the method for preparing it starting from the claimed polydisperse double emulsion.

Water-redispersible granules including at least one active material in the form of a hydrophobic liquid, at least one non-ionic surfactant selected from polyoxyalkylene derivatives, and at least one water-soluble compound selected from polyelectrolytes belonging to the weak polyacid family, are disclosed. A method for preparing such granules by preparing an aqueous emulsion of at least one active material, at least one non-ionic surfactant and at least one water-soluble compound, and drying the resulting emulsion, is also disclosed.

The invention concerns a method for separating particles or molecules whereby these particles or molecules are introduced in a separating medium and a moving force is applied to them in said medium. The method is characterised in that the separating medium is a ferrofluid, i.e. a colloidal suspension of magnetic particles and a magnetic field is applied to this ferrofluid generating therein at least an alternation of a zone rich in magnetic particles and a zone poor in magnetic particles, part at least of the region of the ferrofluid in which this alternation is generated is passed through by the particles or molecules to be separated during their migration.

The invention concerns a process for preparing a secondary emulsion consisting of droplets of a phase A, dispersed in a phase B, A being immiscible in B, starting with a polydispersed primary emulsion of identical formulation and consisting of droplets of the said phase A dispersed in the said phase B, the droplets of the secondary emulsion having a diameter in all cases which is less than the diameter of the droplets of the primary emulsion, characterized in that the starting primary emulsion is viscoelastic and in that the said starting primary emulsion is subjected to a controlled shear such that the same maximum shear is applied to the entire emulsion.

A process for the preparation of aqueous dispersions of magnetizable polymer particles with a narrow distribution from aqueous dispersions with a wide distribution. The amount of water in the aqueous dispersion with a wide distribution is adjusted so that the proportion by weight of magnetizable polymer particles is between about 1 and 40% of said dispersion. The surfactant concentration of the dispersion after the water adjustment is increased until two phases are obtained: a so-called liquid phase and a so-called solid phase. After separation of these two phases is accomplished, these steps are repeated as desired. An aqueous dispersion with a narrow size distribution is recovered.