CN101401955A - Method for producing nano-fibre bracket material with levorotation polylactic acid as base material - Google Patents

Abstract

The invention relates to a preparation method of a nanofiber scaffold material with L-polylactic acid as a matrix. In the present invention, L-polylactic acid is dissolved as a matrix in methylene chloride and dimethylformamide solution, stirred and centrifuged to obtain an electrospinning solution; the polylactic acid solution is then placed in a 5ml glass syringe, and a high voltage is applied; the glass syringe is advanced L-polylactic acid solution in the mixture; the mixed solution is prepared into a nanofiber material film by electrospinning technology; the nanofiber scaffold material is obtained through modification, the fiber diameter is 50nm-500nm, and the fiber porosity is >90%. The invention solves the defects that the PLLA porous scaffold still has too long degradation time, and degradation products easily cause tissue inflammation and the like. The invention has flexible texture, good water and air permeability, excellent tissue compatibility, controllable biodegradability and no antigenicity.

Description

Preparation method of nanofibrous scaffold material based on L-polylactic acid

technical field

The invention relates to the preparation of a tissue repair material, in particular to a preparation method of a nanofiber scaffold material with L-polylactic acid as a matrix.

Background technique

Poly-L-lactic acid (PLLA) belongs to α-polyesters, and the final metabolites of its degradation in vivo are CO ₂ and H ₂ O, which do not accumulate in the body and have almost no toxic and side effects, because of its reliable biological safety, degradability, degradation Features such as adjustability and non-antigenicity have been widely used in the fields of tissue engineering and medicine.

Before the present invention, the PLLA porous scaffold was prepared by thermal gelation technology, which was similar to the structure of natural interstitial cells, and the in vitro culture experiment of neural stem cells was carried out on the scaffold, and the neural stem cells could differentiate on the scaffold, and can promote neurites growth. Using heat-induced phase separation technology and adding PEG-PLLA to prepare PLLA porous scaffolds, the obtained pores are regular and highly connected, and the pore size is easy to control. They were used to culture MC3T3-E1 cells, and the cells proliferated successfully after 4 weeks.

However, the above-mentioned PLLA porous scaffold still has defects such as too long degradation time and degradation products that easily cause tissue inflammation, so it cannot be widely used.

Contents of the invention

The object of the present invention is to overcome the above-mentioned defects and provide a method for preparing a nanofibrous scaffold material based on L-polylactic acid.

Technical scheme of the present invention is:

The main technical feature of the nanofiber scaffold material with L-polylactic acid as the matrix is that the nanofiber scaffold material is obtained by electrospinning with the L-polylactic acid as the matrix, and the fiber diameter is 50nm-500nm, and the fiber porosity is >90%.

Another technical solution of the present invention is:

The preparation method of the nanofibrous scaffold material with L-polylactic acid as the matrix, the main technical steps are:

(1) dissolving L-polylactic acid as a matrix in a mixed solution of dichloromethane and dimethylformamide with a volume ratio of 3:1, magnetic stirring, and centrifugation to remove air bubbles in the solution to obtain an electrospinning solution;

(2) Place the polylactic acid solution in a 5ml glass syringe, and apply a high voltage of 10kv to the needle;

(3) advance the L-polylactic acid solution in the glass syringe at a speed of 0.5ml/h;

(4) The distance between the high-speed rotating wire drum receiver and the needle is kept between 15-20 cm, and the mixed solution is prepared into a nanofiber material film by electrospinning technology;

(5) Modification treatment: put the obtained nanofiber material film into a plasma treatment apparatus, and the reaction conditions are set as discharge power 40W, NH _gas flow rate 20ml/min, pressure 20Pa, and treatment time 40S; The processed nanofiber material membrane was immersed in the type I collagen solution with a concentration of 3mg/ml to react, and was repeatedly washed with deionized water and soaked to remove the physically adsorbed collagen on the surface, and the L-polylactic acid electrospun fiber was vacuum-dried to obtain a nanofiber scaffold Material.

The advantages and effects of the present invention are that the diameter is 50nm-500nm, the porosity > 90% nanometer super ordered fiber, the texture is flexible, has good water permeability and air permeability, excellent tissue compatibility, controllable biodegradability, Non-antigenic.

The invention also has the advantages of simple preparation process and low cost, and can realize mass production. The prepared poly-L-lactic acid (PLLA) nano-super-ordered fiber scaffold material can significantly promote cell adhesion, directional migration, growth and proliferation, has excellent biocompatibility and mechanical properties, stable material properties, and is safe to use Factors produced, conventional disinfection and storage will not destroy its structure and performance.

Other advantages and effects of the present invention will be described below.

Description of drawings

Fig. 1 --Schematic diagram of the electrospinning principle of the present invention (flat receiver 1, receiver moving direction 2, high voltage power supply 3, spinning solution 4, driving device 5).

Fig. 2 - schematic diagram of drum spinning collection device in the present invention (insulated high-speed drum 6, high-speed motor 7, high-voltage power supply 3, spinning solution 4, driving device 5).

Detailed ways

The nanofibrous scaffold is a kind of cell culture substrate emerging in recent years. The nanometer super ordered fiber scaffold has a diameter ranging from 50nm to 500nm, a porosity of >90%, and pores interconnected in three-dimensional directions. The three-dimensional nanoporous polymer scaffold obtained by electrospinning technology is closer in structure to the natural extracellular matrix (ECM), which is conducive to the adhesion and growth of cells, and the extremely small three-dimensional voids in the nanofibrous scaffold promote the formation of cells during the growth process. Mutual influence is conducive to cell differentiation and reproduction. Therefore, the nano-super-ordered fiber scaffold can provide cells with a better microenvironment and realize the true three-dimensional growth of cells.

Using electrospinning technology to prepare L-polylactic acid into a nano-ordered super-ordered fiber scaffold material, based on the advantages of the above-mentioned nano-ordered fiber scaffold and L-polylactic acid, it can be believed that the nano-PLLA super-ordered membrane scaffold material has broad applications in the field of tissue engineering. Application prospects.

Example 1:

1. Preparation of spinning solution: Dissolve L-polylactic acid (PLLA) in a mixed solution of dichloromethane and dimethylformamide (volume ratio = 3: 1), magnetically stir for two hours and centrifuge at 5000 rap/min to obtain By removing the air bubbles in the solution, a uniform and stable spinning solution can be obtained.

2. Preparation of nanofiber membrane: as shown in Figure 1, the above-mentioned L-polylactic acid solution is placed in the driving device 5, in the glass syringe of 5ml (No. Propel the poly-L-lactic acid solution in the glass syringe at a speed of ml/h, use the flat receiver 1 as a collection device for nanofibers, and keep the distance between the collection device and the needle at 15-20 cm. The prepared L-polylactic acid nano-super ordered fiber membrane was stored at room temperature and dried under vacuum for future use.

3. Modification of nanofibrous scaffold materials: the nano-super ordered fiber material obtained in step 2 is modified by low-temperature plasma technology and coated with type I collagen, and the prepared fiber samples are placed in a self-made plasma processor Middle (outer electrodes, electrode spacing is 6cm), equipped with SY type crystal-controlled RF power source (300W, Beijing Microelectronics Center), the reaction conditions are set as: discharge power 40W, NH ₃ gas flow rate 20ml/min, pressure 20Pa, treatment Time 40S. The plasma-treated fiber samples were immersed in a solution of type I collagen (Sigma, USA) with a concentration of 3 mg/ml to react for 24 h, washed with deionized water repeatedly and soaked for 24 h to remove the physically adsorbed collagen on the surface, and the poly-L-lactic acid The electrospun fiber was cut into a film with a size of 15mm×15mm and dried in vacuum for later use.

Example 2:

1. As in step 1 in Example 1.

2. Preparation of nanofiber membrane: as shown in Figure 2, place the above-mentioned L-polylactic acid solution in a 5ml glass syringe (No. 6 needle), apply a high voltage of 10kv to the needle, and advance at a speed of 0.5ml/h The L-polylactic acid solution in the glass syringe utilizes the high-speed rotation of the high-speed motor 7, and the insulated high-speed (wire) roller 6 receiver 1000r/min is used as a collection device for nanofibers, and the distance between the collection device and the needle remains between 15-20cm between. The prepared L-polylactic acid nano-super ordered fiber membrane was stored at room temperature and dried under vacuum for future use.

3. Modification of nanofibrous scaffold material: as step 3 in Example 1.

Example 3:

1. As in step 1 in Example 1.

2. Preparation of nanofiber membrane: as shown in Figure 2, place the above-mentioned L-polylactic acid solution in a 5ml glass syringe (No. 6 needle), apply a high voltage of 10kv to the needle, and advance at a speed of 0.5ml/h The L-polylactic acid solution in the glass syringe utilizes the high-speed rotation of the high-speed motor 7, and the insulated high-speed (wire) roller 6 receiver is used as a collection device for nanofibers at 2000r/min, and the distance between the collection device and the needle remains at 15-20cm between. The prepared L-polylactic acid nano-super ordered fiber membrane was stored at room temperature and dried under vacuum for future use.

3. Modification of nanofibrous scaffold material: as step 3 in Example 1.

Claims (3)

1. Taking L-polylactic acid as a matrix nanofibrous support material, it is characterized in that taking L-polylactic acid as a matrix, by electrospinning, to obtain a nanofibrous support material, its fiber diameter is at 50nm-500nm, and the fiber porosity > 90%. 2. take L-polylactic acid as the preparation method of the nanofiber support material of matrix, its step is: (1) dissolving L-polylactic acid as a matrix in a mixed solution of dichloromethane and dimethylformamide with a volume ratio of 3:1, magnetic stirring, and centrifugation to remove air bubbles in the solution to obtain an electrospinning solution; (2) Place the polylactic acid solution in a 5ml glass syringe, and apply a high voltage of 10kv to the needle; (3) advance the L-polylactic acid solution in the glass syringe at a speed of 0.5ml/h; (4) The distance between the high-speed rotating wire drum receiver and the needle is kept between 15-20 cm, and the mixed solution is prepared into a nanofiber material film by electrospinning technology; (5) Modification treatment: put the obtained nanofiber material film into a plasma treatment apparatus, and the reaction conditions are set as discharge power 40W, NH _gas flow rate 20ml/min, pressure 20Pa, and treatment time 40S; The processed nanofiber material membrane was immersed in the type I collagen solution with a concentration of 3mg/ml to react, and was repeatedly washed with deionized water and soaked to remove the physically adsorbed collagen on the surface, and the L-polylactic acid electrospun fiber was vacuum-dried to obtain a nanofiber scaffold Material. 3. the nanofiber scaffold material preparation method taking L-polylactic acid as a matrix according to claim 2, is characterized in that the outer electrodes and the electrode spacing of the plasma treatment instrument are 6cm.