Preparation method for drug-carrying multi-layer tissue engineering micro-nano structure bracket
The invention discloses a preparation method for a drug-carrying multi-layer tissue engineering micron-nano structure bracket. The preparation method comprises the following steps: firstly, preparing cellosilk by adopting the electrospinning technology, and collecting the cellosilk in a culture dish to obtain a layer of fibrous membrane; preparing microspheres by adopting the micro flow control technology, wherein diameters of the microspheres are controlled within 100-300 microns; mixing the obtained microspheres in oil phase and receiving directly on the fibrous membrane, settling the microspheres on the fibrous membrane, and absorbing away the oil phase after one layer of the microspheres is overspread; spraying a layer of the fibrous membrane on the microspheres directly through the electrospinning technology to obtain a micro-nano structure with a layer of microspheres and two layers of fibrous membranes; repeating n times according to the order to finally prepare a three dimensional frame structure containing micron-sized microspheres and nano-sized fibrous membranes and with n layers of microspheres and n+1 layers of fibrous membranes. The bracket can excellently simulate extracellular matrix environment; additionally, lyophilic drugs and hydrophobic drugs can be respectively added into the microspheres and the fibrous membranes, so that two drugs are released simultaneously to better promote the repairing of tissues. 1. A multi-layer tissue engineering to carry the drug of the process for the preparation of micro-nano structure support, comprising the following means: 1) 14-25 parts weight of biodegradable high-molecular material, proper amount of parts weight of the hydrophobic drug and 86-75 the share is heavy organic solvent uniformly as the spinning solution, prepared by using electrostatic spinning technology after the fiber filament, in will be collected in the culture dish, that is, into a layer of fiber membrane; 2) 0.227-0.910 parts weight of calcium carbonate, 1-2 parts weight of sodium alginate, proper amount of parts weight of hydrophilic drugs are evenly mixed with distilled water, as the aqueous phase of the micro-fluidic system; the 0.21-1.05 parts weight of acetic acid, 8 parts weight of castor acid poly glycerlol and 100 parts major soyoil mix, the oil phase as a micro-fluidic system; the microfluidic device after preparation, to control the diameter of the micro-fluidic device for controlling the velocity of flow of the prepared 100-300 micron calcium alginate microsphere; 3) will 2) mixing of the obtained microspheres is uniformly received in the oil phase in 1) on the resulting fiber membrane, standstill, microsphere due to gravity settling on to the fiber membrane, through controlling the receiving time and the received density of the microspheres can be filled with a layer of, suction losing oil phase; by 1) the electrostatic spinning is sprayed on to the layer of microspheres a layer of fiber membrane, to obtain two layers of the fiber is made of a layer of calcium alginate microsphere-sandwich structure; 4) is performed once again, 3) operation, implementation by from now onlevel microballoons n n, n+ 1 layer fiber membrane for the target structure of the three-dimensional three-dimensional support. 2. Drug carrying micro multi-layer tissue engineering method for the preparation of the structure according to Claim 1, characterized in that the electrostatic spinning the technical parameter is : (1) spinning voltage: 15-24KV ; (2) spinning temperature: room temperature ; (3) spinning distance: 12-20cm ; (4) the advance speed of the spinning solution: 0.5-2.5 ml/h. 3. Drug carrying micro multi-layer tissue engineering method for the preparation of the structure according to Claim 1, characterized in that the process parameters states the micro class to control : (1) the aqueous phase the advance speed: 0.08-0.1 ml/h; oil phase the advance speed: 2.0-3.0 ml/h. 4. Drug carrying micro multi-layer tissue engineering method for the preparation of the structure according to Claim 1, characterized in that the organic solvent is one of the following substances: N, N-dimethyl formamide and methylene chloride mixed solution (volume ratio of 1:3); N, N-dimethyl formamide and methylene chloride mixed solution (volume ratio of 1:3); acetone; dichloromethane ; N, N-dimethyl formamide and methylene chloride mixed solution (volume ratio of 1:1); dichloromethane. 5. Drug carrying micro multi-layer tissue engineering method for the preparation of the structure according to Claim 1, characterized in that the biodegradable polymer material is poly-ε-caprolactone, polylactic acid, polylactic acid-glycolic acid copolymer, polylactic acid-polyethylene glycol copolymer, polyanhydride; hydrophobic medicament is dexamethasone, tretinoin, tranilast; hydrophilic drug for bone morphogenetic protein, a transforming growth factor, vascular endothelial growth factor, platelet derived growth factor, bovine serum albumin, tea-toxicarol.