Method for preparing carbamazepine PLGA (poly lactic-co-glycolic acid) copolymer micro capsule

Abstract

The invention provides a method for preparing a carbamazepine PLGA (poly lactic-co-glycolic acid) copolymer micro capsule through a supercritical fluid injection method. The method comprises the following steps: firstly dissolving carbamazepine into supercritical carbon dioxide; secondly, feeding the supercritical carbon dioxide which is dissolved with the carbamazepine into a substrate to be maintained for 1 to 5 hours through the plasticization and swelling of PLGA copolymer, and enabling the carbamazepine to be balanced in distribution between the supercritical carbon dioxide and the PLGA copolymer; finally escaping the carbon dioxide, reserving the carbamazepine in the PLGA copolymer substrate, and preparing the carbamazepine PLGA copolymer micro capsule. The carbamazepine PLGA copolymer micro capsule which is prepared through the method is high in solubility and dissolution rate.

Description

technical field [0001] The invention relates to a method for preparing carbamazepine polylactic acid-glycolic acid copolymer microcapsules. Background technique [0002] The dissolution rate and dissolution rate of crystalline drugs in aqueous solution are generally relatively low, and it is usually necessary to disperse the drug in a polymer carrier to improve the dissolution rate. The biopharmaceutical classification system divides drugs into four types according to their dissolution rate and permeability in the gastrointestinal tract, among which type II drugs have low dissolution rate and good permeability, so increasing the dissolution rate of type II drugs is the research goal important direction. When the dose of type II drugs is not high, the connection between in vitro and in vivo experiments can predict the dissolution rate, so the dissolution test can provide useful information for the bioavailability of the drug. [0003] There are many difficult problems in th...

AI Technical Summary

Problems solved by technology

[0003] There are many difficult problems in the preparation of drug microcapsules by traditional methods, such as the low encapsulation efficiency of the emulsification-solvent evaporation method, the slow and controlled release effect is not good, and a large amount of organic solvents and surfactants are used in the preparation process; the spray drying method is based on the boiling point of the solvent, The selected inlet air temperature is higher; the product particle size of the ball milling method is larger and the distribution is wider, etc.

These problems lead to the difficulty of separating and purifying the product, the preparation conditions are not suitable for heat-sensitive drugs and biologically active substances, and the low bioavailability of the product.

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