| Background:Tissue engineering,a comprehensive subject area,combines the limitations of traditional organ transplantation and biomaterial transplantation through the combination of cell biology and materials science.Development of alternatives to artificial organs and tissues such as muscles,bones,cartilage,tendons,artificial blood vessels,and skin;development of artificial artificial organs,such as artificial heart,liver,kidney,etc.,to replace or repair damaged tissue;Finally,an organ or tissue having a three-dimensional structure is formed.And no need for adjuvant therapy,this can not only improve the cure rate,but also can greatly reduce the cost of treatment.Scaffolding materials are an important part of tissue engineering.Among the many different kinds of tissue scaffolding materials,aerogel materials are gradually being understood and gradually applied in the biomedical field.Cellulose cellulose is a natural macromolecule with the largest reserves,widest distribution,and renewable biodegradability.Cellulose aerogel prepared from cellulose is a new type of lightweight functional scaffold containing fibrous structure.It has the unique advantages of fiber structure while possessing the characteristics of traditional inorganic particle aerogels.Due to the advantages of both renewable natural polymers and high porosity nanoporous materials,cellulose aerogels have characteristics such as good toughness and easy processing,relative to poor strength and fragile inorganic aerogels,sound-absorbing and heat-insulating materials and medical biomaterials have potential applications of great potential.It is known as a new generation of aerogels after inorganic aerogels and synthetic polymer aerogels.Chitosan is the product of deacetylation of chitin,the only basic polysaccharide in nature.It is a natural high-molecular compound that has low antigenicity,biodegradability,good biocompatibility,and safe and non-toxic degradation products.It is widely used in tissue engineering scaffold materials.In this experiment,a novel scaffold material was prepared from cellulose aerogel mixed chitosan,and its morphology,chemical state,surface element distribution,and pore structure were analyzed;At the same time in such aspects as biocompatibility of in vitro studies,this paper discusses the cytotoxicity of aerogel materials and the presence of different concentrations of chitosan composite aerogel form of MC3T3 E1-cell proliferation,the influence of aerogel for further research in tissue engineering scaffold material provides new ideas.Methods:Cellulose was prepared by suspension gelation at a concentration of 3%,5%cellulose aerogel CA and mixed with chitosan solution on the basis of 3%cellulose.Chitosan composite aerogel(cellulose/chitosan aerogel CCA)in which the mass of the chitosan solution accounts for 20%,40%and 60%of the total mass of the mixed solution.Scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FT-IR),X-ray energy dispersive spectroscopy(XPS)and specific surface area porosimetry(BET)are applied to the morphology and chemistry of aerogel materials.The state,surface element distribution and pore structure were analyzed;the compression mechanics performance of the material was tested by a universal testing machine;the degradation of the material was evaluated by measuring the weight loss rate and the water absorption rate of the material;and the biocompatibility of the material was evaluated by the cytotoxicity test.MC3T3-E1 cells were inoculated directly onto aerogel scaffolds and cultured for 1,3,5,and 7 days.The proliferation of MC3T3-E1 cells on the surface of cells was detected by MTT assay.Results:1.Preparation of Cellulose Aerogels and Their Composites:Chitosan/cellulose composite aerogels prepared using droplet-suspension gel forming method have a uniform cylindrical shape;pores in the CA surface network can be seen by SEM electron microscopy.Loose and flaky lamellar aggregation occurred.The porosity of 3%CA was slightly larger than that of 5%CA,and it was more lose.CCA clearly showed that chitosan molecules were entrapped in the network and the chitosan solution concentration was higher.The more chitosan,the smaller the porosity.2.BET results showed that the average pore sizes of 3%CA,5%CA,20%CCA,40%CCA,and 60%CCA were 17.63 nm,14.72 nm,13.46 nm,20.87 nm,and 15.49 nm,respectively;the specific surface area was respectively 12.67m ~2/g,8.85 m ~2/g,14.83 m~2/g,13.23 m~2/g,and 12.58 m~2/g;FT-IR results show no chemical reaction of chitosan molecules successfully introduced into CA materials;XPS analysis The results of the elemental content of the material showed that with the increase of chitosan content,the nitrogen content increased.3.Compressive strength testing by universal testing machine,the material with the increase of cellulose concentration,the material can withstand the compressive force increases,the material with the increase of chitosan content,the beginning of the compressive strength gradually weakened,but the late trend According to the results,the weight-loss test showed that the weight loss rate of CCA was higher than that of CA after soaking in PBS solution for 30 days,and the weight loss rate increased with the increase of chitosan content.The water absorption experiment showed that the material had good water absorption.Increased chitosan content increased water absorption.4.Cytotoxicity:The cytotoxicity of the extract with 5%CA and 20%CCA was grade0,and the cytotoxicity was 3%with CA,40%with CCA,and 60%with CCA.The aerogel material was compared with the blank control group.There was no significant difference in the extract group(P>0.05)5.Cell proliferation:MTT assay results showed that compared with the control group,all CA and CCA materials promoted the proliferation of MC3T3-E1 cells to varying degrees(P<0.05),and the promoting effect of 40%CCA was significantly better than other Group(P<0.01).Conclusions:1.Cellulose aerogel and cellulose network-encapsulated chitosan composite aerogel materials were successfully prepared by droplet-suspension gel forming method.The aerogel material has extremely rich nanopore structure and extremely light appearance.density.In the aerogel,cellulose molecules and chitosan molecules are intertwined by hydrogen bond polymerization.The preparation process is a physical gel process without chemical crosslinking reaction.Chitosan is successfully introduced into the CA matrix without chemical changes.2.The 5 kinds of materials have certain mechanical strength.The introduction of chitosan in CA can increase the degradation rate and hydrophilicity of the material.With the increase of chitosan content,the hydrophilicity increases,which facilitates the diffusion of nutrients between the matrix and the exchange of related media.3.Cytotoxicity results showed that the cytotoxicity of 3%CA,5%CA,20%CCA,40%CCA,and 60%CCA material extracts on MC3T3-E1 cells were all grade 1 and were within safe limits;Cell proliferation requirements.Description aerogel scaffold material has good biocompatibility4.The proliferation of MC3T3-El cells was better than that of CA stents on CCA scaffolds,of which 40%of CCA had the best proliferation effect,indicating that CCA has certain feasibility in the application of tissue engineering scaffolds. |
PDF Full Text Request