Other

Bio Syntech

Piramal Healthcare (canada) Ltd.

Biosyntech Canada, Inc.

Oligo Medic Inc

Piramal Healthcare Limited

Amine Selmani

Abdellatif Chenite

Cyril Chaput

Mohammed Berrada

Fayrouze Jalal

Dong Wang

Fouad Dabbarh

Christele Combes

The present disclosure relates to a method which allows direct formation of gel-like solutions of polyglucosamine at neutral pH&#x2248;7 to 8, eliminating the need of prior dissolution of polyglucosamine in acidic environment; and to a homogeneous liquid combination of polyglucosamine-glyoxylate with hyaluronan.

Composition comprising polyglucosamine-glyoxylate solutions mixed with hyaluronan

The present invention relates a biopolymeric liquid aqueous composition for producing self-gelling systems and gels, which comprises: an acidic water-based medium, 0.1 to 10% by weight of a pH-gelling acid-soluble biopolymer; and 0.1 to 10% by weight of a water-soluble molecule having a basic character and a pKa between 6.0 and 8.4, or a water-soluble residue or sequence of the molecule having a basic character and a pKa between 6.0 and 8.4. The liquid composition has a final pH ranging from 5.8 and 7.4, and forms a stable solid and homogeneous gel within a temperature range from 10 to 70&#xb0; C. The present invention also relates to a method for preparing the composition and uses thereof.

Temperature controlled and pH dependent self gelling biopolymeric aqueous solution

The present disclosure relates to a chitosan solution neutralized with amino-sugar carbonate buffering solution or amino-sugar phosphate buffering solution or phosphorylated aminosugar buffering solution. The resulting thermogelling chitosan composition is highly biocompatible, isotonic and has the ability to rapidly turn into gel upon heating to the body temperature. It provides a novel chitosan-based composition to suitable for drug delivery, cell delivery and repair or regeneration of tissues and organs as well as other clinical treatment.

Highly biocompatible dual thermogelling chitosan/glucosamine salt composition

Highly biocompatible dual thermogelling chitosan/glucosamine salt compositions

In accordance with the present invention there is provided a new composition and method for chemically modifying chitosan, including N-substituting or N-cross-linking, under homogeneous conditions by providing neutral aqueous chitosan solutions with enhanced reactivity. The method comprises the steps of i) preparing a clear aqueous solution of chitosan, said solution comprising 0.1 to 10% by weight of a chitosan, and 0.1 to 20% by weight of at least one buffering agent having a pKa between 6.0 and 7.6, said solution having a pH ranging from 6.8 to 7.2; and ii) dissolving homogeneously at least one reagent into the solution of step a), said reagent being reactive toward amine groups of chitosan; and said reagent being at a concentration from 0.01 to 10% by weight. The chitosan in the aqueous solution is chemically modified or cross-linked by a selective substitution on the amino group of chitosan.

Composition and method to homogeneously modify or cross-link chitosan under neutral conditions

The present invention relates a temperature-controlled pH-dependant formation of ionic polysaccharide gels, such as chitosan/organo-phosphate aqueous systems, and methods of preparation thereof. While chitosan aqueous solutions are pH-dependant gelating systems, the addition of a mono-phosphate dibasic salt of polyol or sugar to a chitosan aqueous solutions leads to further temperature-controlled pH-dependant gelation. Solid organo-phosphate salts (1-20% w/v) are added and dissolved at low temperature (10&deg; C.) within 0.5 to 4.0% w/v chitosan in aqueous acidic solutions. Aqueous chitosan/organo-phosphate solutions are initially stored at low temperatures (4&deg; C.), then endothermally gelated within the temperature range of 30 to 60&deg; C. Chitosan/organo-phosphate solutions rapidly turn into gels at the desired gelation temperature. Gelation can be ex vivo within any receivers or molds, or in situ in animals or humans (in vivo) so as to fill a tissue defect or cavity.

Temperature-controlled pH-dependent formation of ionic polysaccharide gels

The present invention relates to a new method for the production of polymer microparticles. The method is carried out in the absence of organic solvent, and consists in the steps of (a) combining first and second polymers, the first and second polymers being immiscible, (b) heating the combination obtained in step (a) so as to melt the first and second polymers; (c) stirring the melted polymers obtained in step (b) under conditions effective to produce a biphasic system comprising a dispersed phase consisting of a dispersion of the first polymer and a matrix continuous phase comprising the second polymer, the dispersed phase containing microparticles of the first polymer dispersed in the matrix continuous phase; (d) solidifying the biphasic system obtained in step (c) so as to keep the microparticles of the first polymer dispersed in the matrix continuous phase; and (e) separating and isolating the microparticles of the first polymer from the matrix continuous phase, wherein the first polymer forming said dispersed phase is water-insoluble, while the second polymer forming the continuous phase is water-soluble.

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Montréal, Canada

Amine Selmani