Process for the preparation of enteric alginate microcapsules by ionic gelation containing diclofenac or one of its salts and multiparticulate pharmaceutical composition containing them

摘要

Process for preparing enteric microcapsules of calcium alginate of homogeneous composition containing diclofenac or one of its salts, characterized in that it comprises the following steps: A) preparing a solution of an alginate salt, selected from sodium, potassium or ammonium alginate , in water-ethanol and dissolve under stirring diclofenac or one of its salts in the presence of a surfactant selected from the group consisting of sorbitan monostearate, sorbitan monooleate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monolaurate and sodium bicarbonate, sodium bicarbonate a temperature below 60 ° C; B) incorporate the solution obtained in A) into a solution of calcium chloride controlling the temperature below 60 ° C, during the whole process; C) resuspend the microcapsules formed and isolated without prior drying in a solution of said alginate salt, with a concentration between 0.05% and 0.1%, with stirring for 30 to 120 minutes at room temperature; D) filtration, drying and sieving successively by 1000 and 250 micron meshes, selecting for the preparation of the pharmaceutical composition only the fraction of microcapsules obtained and of size between both meshes, in which the microcapsules obtained and selected have a active substance content exceeding 55%; E) and optionally, convert the microcapsules thus obtained into extended release microcapsules.