Preparation,Degradation And Drug Release Of Fe₃O₄ Complex Film In Vitro

Postoperative adhesions have a high incidence and are highly susceptible to a range of complications and are a common symptom after surgical procedures.The paper adopts a physical barrier strategy,using poly（lactic acid-glycolic acid）copolymer（PLGA）,a biomedical and pharmacological material approved by the U.S.Food and Drug Administration（FDA）,European Medicines Agency and China’s Food and Drug Administration for in vivo use,as the matrix material,and adding less toxic and more clearly metabolized ferric tetroxide particles to form a complex film,while loading the drug with a view to achieving At the same time,the magneto-thermal effect of the magnetic particles can promote wound repair and the loaded drug can enhance wound repair and further disease treatment.In this paper,the degradation behavior of this complex film in vitro is systematically investigated,and the release behavior of different types of drugs in vitro is also carefully discussed.Firstly,in order to improve the dispersion,colloidal stability and biocompatibility of superparamagnetic Fe₃O₄ nanoparticles,ferric tetroxide particles modified with different small molecules containing carboxyl groups:Fe₃O₄@Glycine（Fe₃O₄@Gly）、Fe₃O₄@Glycolic acid（Fe₃O₄@GA）、Fe₃O₄@Oleic acid（Fe₃O₄@OA）and Fe₃O₄@citric acid（Fe₃O₄@CA）were prepared by co-precipitation method,and their structure,morphology and magnetic properties were investigated.The results showed that different molecules modified the structure and properties of the ferric tetroxide particles.Next,four nanoparticles,Fe₃O₄@GA,Fe₃O₄@Gly,Fe₃O₄@CA and Fe₃O₄@OA,were added to PLGA to prepare complex films.The PLGA pure membranes were used as a reference to explore their degradation behaviors in deionized water,pH 5.0,pH 7.4 and pH 8.0 environments.It was found that the degradation of various membranes was the fastest under alkaline conditions,followed by deionized water,pH5,and pH7.4.The degradation rate of the four complex membranes was roughly Fe₃O₄@CA-membrane>Fe₃O₄@Gly-membrane≈Fe₃O₄@GA-membrane>Fe₃O₄@OA-membrane.Compared to PLGA pure films,the addition of Fe₃O₄ accelerated their degradation,and the degradation rate increased with the increase of magnetic nanoparticle content.Finally,the drug loading properties were studied by adding simulated drugs to the magnetic nanoparticle composite films.The results showed that the sudden release of water-soluble drugs was obvious,and the larger the molecular weight,the more serious the sudden release.The non-water-soluble drugs basically have no sudden release phenomenon,and the slow release of drugs is basically in a first-order release pattern.The drug release pattern is consistent with the degradation law,and the fastest drug release is Fe₃O₄@CA-membrane,and the slowest is Fe₃O₄@OA-membrane.In summary,this paper synthesized Fe₃O₄@GA,Fe₃O₄@Gly,Fe₃O₄@CA,Fe₃O₄@OA complex films based on PLGA,and studied their degradation and drug loading behaviors in vitro to lay the theoretical and practical foundation for the use of complex films for practical postoperative anti-adhesion.