Controllable biodegradable plga inner pore gradient membrane and its preparation process

Abstract

The invention relates to a controllably biodegradable poly(lactic-co-glycolic acid) (PLGA) bore gradient membrane and a preparation process thereof. The PLGA bore gradient membrane is of a central symmetrical structure with smooth external and porous internal and is formed by sequentially arranging and pressing seven layers of equant and thickness-equal films having thickness of 10-50 microns: PLGA 5050 FILM, porous PLGA6535film, porous PLGA7525film, porous PLGA8515film, porous PLGA7525 film, porous PLGA6535film and PLGA5050film. Compared with the prior art, the PLGA bore gradient membrane is smooth in surface and porous in internal; the mass percent content of the monomer from outside to inside (to half thickness) is distributed in gradient manner; the sudden-drop of the mass of the PLGA in the degradation process is overcome, the integral degradation curve is gentle and stable and free from sudden-drop; the degradation process is properly accelerated due to the existence of the bore, the degradation speed of the finished product is controllable, the mechanical strength is high, the method is simple and easy to operate, the obtained product is stable in quality and wide in application prospect.

Description

technical field [0001] The invention relates to a biodegradable material and its preparation process, in particular to a controllable biodegradable PLGA inner hole gradient film and its preparation process, belonging to tissue repair materials, drug slow-release materials, and auxiliary materials for local drug delivery technology. Background technique [0002] Lactic acid-glycolic acid copolymer (poly(lactic-co-glycolic acid), PLGA), also known as lactic acid-glycolic acid copolymer, lactide-co-glycolide copolymer, polyethylene lactide, etc., is a biologically Degradation of polymer materials. PLGA has been approved by the U.S. Food and Drug Administration (FDA) as a Safe materials for tissue repair and drug sustained release have been widely used in the field of biomedicine, such as: skin grafts, wound sutures, implants in vivo, micro-nano particles, etc. [0003] PLGA is formed by the copolymerization of two monomers, lactic acid (PLA) and glycolic acid (PGA), and its ...

AI Technical Summary

Problems solved by technology

[0004] Solvent casting / particle leaching technology was proposed by MiKos (US Patent US5514378). This technology uses organic solvents and particles insoluble in organic solvents such as sodium chloride and sugar crystals as porogens. The pore size can be adjusted. It is the most convenient, One of the most widely used methods, it can be applied to the preparation of three-dimensional porous cell scaffolds with high voids and internal connectivity, which can be used for drug loading and cell culture, but it cannot meet the needs of local drug delivery. Require

[0005] Chinese patent CN1857730 discloses a PLGA multi-cavity body with micropores, and its microporous structure helps to overcome the hysteresis of initial release and the phenomenon of burst release in the middle period existing in the existing implantable sustained-release drug delivery system

However, the degradation behavior of more PLGA series and porous membranes has not been investigated

[0007] In addition, there is no patent on PLGA that can achieve degradation without burst release, moderate mechanical strength, and effectively shorten the infiltration time only by virtue of its own structural modification and simple equipment and operations.

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