The Fabrication Of Modling PLGA/HA Nanofibrous Scaffolds By Electrospinning Technology And Its Biological Performance

In the area of study of bone tissue engineering，there are many shortage inscaffoldds materials.To prepare a ideal scaffold with good mechanics， biologyand morphology is key in study. Poly-lactic-co-glycolic acid (PLGA) is wideapplication with well molding，degradatiable and biocompatibility in organicpolymer biological material. To overcome the shortage of mechanical strengthen,bone binding force and long degradation time，we wish to add β-Tricalciumpoosphate (β-TCP) which has good cell adhesion and mechanical stregthen andshort degradation time. Outside chiston/gelatin core maded by freeze-dryingmethod，prepare a PLGA/β-TCP nanofibers maded by electrospinning method toform a new scaffold with molding macroscopic structure, good three-dilemater ofmicroscopics tructure， well cell compatibility and right regeneration time. Methods：1. The PLGA/β-TCP nanofibrous was prepared by using electrospinningmethod(Voltage=10Kv,Distance=10cm). The solute was PLGA and β-TCPmixture(10group of different quality ratio：10：0，9：1，8：2，7：3，6：4，5：5，4：6，3：7，2：8，1：9，0：10) and the solvent weretrichloromethane and acetone （2：1）. The contact angle was measured bycontact angle measuring system to determine the hydrophilic. The porosity ofscaffolds was measured by liqiud replacement method. PBS liqiud including1%pancreatic enzyme was chosen as simulated body fluid to perform in vitroimmersion experiment The weightlessness rate of spacimens were observed toevaluate the biodegradation of scaffolds.The best ratio of materials waschosen from hydrophilic， porosity and degradation time. Meantime themicrostructure was observated by SEM.2. The chiston/gelatin(quality ratio=1：1) cores were prepared by freeze-dryingmethod， the solvent was1%acetic acid. After-80℃freeze-drying, the norecarriers with three-ditermines structures were made(the shape was cutted byneed).The molding PLGA/β-TCP nanofibrous scaffolds was prepared bymaking the molding chiston/gelatin fibrous scaffolds as receptors.3. According to the GB and YY-T standard, the spacimens were tested with the invitro cytotoxicity test， hemolytic test.4. The obsteoblast cells were cultured on molding chiston/gelatin scaffolds,PLGA nanofibers and PLGA/β-TCP nanofibrous scaffolds. Short timeculturing time were30min，60min and120min. After incubating for1day,cultured the three group materials in non-cell blood serum medium.CellMetabolic activity were investigated using MTT assay. Morphology analysiswas observated by SEM. Results：1. Four groups (the quality ratio=10：0，9：1，8：2，7：3) can producenanofibers,the rest groups were particulate matters， not continuousnanofibers,not fit experimental requirements.2. Among the four groups， the more β-TCP of materials were, the lesshydrophilic were， the more porosity were and the faster the whole scaffolds’degradation speed were. So when the quality ratio of PLGA and β-TCP was7：3，the prepared nanofibrous scaffold were ideal ones.3. The results of in vitro cytotoxicity test showed that the molding PLGA/β-TCPscaffolds had no cytotoxicity. The result of hemolytic test showed that thehemolytic rates of all specimens were lower than5%.4. After culturing on the surface of materials30min,60min and120min, celladhesion of PLGA/β-TCP nanofibrous scaffolds were the most,chiston/gelatin were the second and the the PLGA nanofibers were least5. After1d culture，every group MTT has no differences in statistical（p＞0.05）.the images showed that cells in every group growed well and began to spread.After4d and8d， MTT of the PLGA/β-TCP was higher than PLGA andchiston/gelatin （p＜0.05）. SEM images showed that cells in groups growedwell and could see cells’ locomotion growed into the holes of materials andspreaded. The cell number of PLGA/β-TCP were more than PLGA andchiston/gelatin groups.cells first adhered molding PLGA/β-TCP group，after4d cells were relativelyflatter and after8d it showed that filopodia extended into holes.Conclusions:Using PLGA/β-TCP solvent with quality ratio7：3， preparedthree-dimensional nanofibers with good cell adhesion and right regration time by electrospinning methods. Preparing molding nore of chiston/gelatin byfreeze-drying method in order to produce an ideal PLGA/β-TCP nanofibrousscaffolds. These scaffolds had good safity and biocompatibility，well molding andcell adhesion and proliferation，right degration time.