KR102353345B1 - A manufacturing method of powder of silk fibroin - Google Patents

Abstract

A silk fibroin powder according to the present invention is not recrystallized by hydrolysis or dissolution using enzymes or other drugs during manufacture, but is powdered using only dry mechanical grinding means, so that it is possible to maintain the nanostructure of silk without destroying the unique nanostructure of silk, thereby being able to be applied to various medical technologies such as diagnosis, treatment, a biosensor, and a non-replicable bio-transplantation code, and can be widely used in biodegradable polymers including fibroin powder, pharmaceuticals, cosmetics, and functional foods.

Description

A manufacturing method of powder of silk fibroin

The present invention relates to a method for producing silk fibroin powder, and more specifically, by pulverizing a cocoon, which is difficult to cut or pulverize, into a fine powder through a physical pulverization method, without destroying the inherent nano-molecular structure of silk, it can be made into a powder of 100 μm or less. It relates to a method for producing a possible silk fibroin powder.

The cocoon is made by the house silkworm (Bombyx mori) to protect the pupae. In the meantime, mankind has used it as a raw material for manufacturing silk, a high-quality textile material. Silk is known to be the longest, thinnest and toughest fiber obtained in nature. Therefore, research and analysis on silkworm cocoons have been researched and developed mainly limited to characterization as a material for textiles.

Silkworm yarn consists of two fibroin proteins and a protein called sericin that envelops them. Sericin protein is water-soluble and easily degraded by enzymes, but fibroin protein, a hydrophobic structure, is not easily degraded by enzymes.

Fibroin is the main protein of silk fibers that exhibits silk's unique luster and elasticity. It has excellent biocompatibility and moisture retention properties, so it can be used in biomedical applications (film, fabric, net, mesh), It is widely used in membranes, yarns, sponges, hydrogels, tissue regeneration supports, etc.), and sericin is known to have good moisturizing properties, adhesion properties, and human body compatibility.

In addition, it has recently been demonstrated that the cocoon's unique nanostructure causes Anderson's photocoagulation. Anderson's agglomeration is a phenomenon in which the conduction of waves is lost by an irregular structure and is trapped inside. This phenomenon occurs well when interference between scattered waves occurs well or when the intensity of scattering is strong. Nanofibers aligned side-by-side align the scattering directions of light so that the scattered waves have a good coherence and interfere with each other with a high probability, Multiple nanofiber scatterers with a size similar to the wavelength of light maximize the scattering intensity, so they function similar to optical fibers that trap and transmit light, or create a strong interaction between biomaterials and light, so that diagnosis, treatment, It is expected that various medical technologies such as biosensors and non-replicable bioimplantable passwords will be developed.

However, since the cocoon itself has a fibrous form, there are restrictions on its use, and because it is formed to protect the inner moth larva, it has high crystallinity and molecular weight, and is optimal for use as a fiber due to its strong strength. However, it is very difficult to pulverize and has a problem of high processing cost. In particular, although it differs depending on the species of silkworm, the tensile strength at cut is 18 MPa up to 90 MPa or more, and the thickness of the silk layer, which is the weight per unit thickness, also has a fairly dense structure of 0.3 to 0.8 g/mm, so it is very difficult to physically cut it.

For this reason, most silk powder production technologies have been proposed in which silk is enzymatically decomposed or dissolved in acid or salt to form a liquid and then powdered. In addition, it is very difficult to control the molecular weight by using acid or salt, and by using high molecular weight or harsh conditions even after neutralization, gelation, sediment and low molecular weight are required due to attraction and repulsion between protein molecules at a specific hydrogen ion concentration. It is causing limitations in the product process, such as the rapid leakage of Above all, when silk is dissolved, the above-described nanostructure is destroyed, so it cannot form a nanofiber scatterer, so it cannot be used as a biosensor.

Republic of Korea Patent Registration No. 10-02866388 (January 12, 2001)

The present invention has been devised to solve the above problems, and by pulverizing the cocoon, which is difficult to cut or pulverize, through a physical pulverization method, it is possible to pulverize the silk to a size of 100 μm or less without destroying the unique nano-molecular structure of silk. An object of the present invention is to provide a method for preparing silk fibroin powder.

The present invention relates to a method for producing silk fibroin powder.

One aspect of the present invention is

a) a refining step of refining the cocoon by contacting the refining solution to the cocoon;

b) a first pulverizing step of pulverizing the refined cocoon into short fibers using a dry mechanical pulverizing means; and

c) a second grinding step of pulverizing the short fibers into a fine powder having an average particle size of 100 μm or less by pulverizing the short fibers with a dry mechanical grinding means;

It relates to a method for producing silk fibroin powder comprising a.

In the present invention, step a) is carried out by contacting the cocoon with any one or a plurality of scouring solutions selected from an aqueous alkali solution, an acidic aqueous solution, an enzyme aqueous solution, and an amine aqueous solution set at 50 to 200 ° C. for 0.1 to 5 hours,

The step b) is carried out using a powder mixer equipped with an impeller, the revolution speed of the impeller is 10 to 50 rpm, and the grinding speed of the cocoon is 1,000 to 15,000 rpm, and grinding for 1 to 5 minutes characterized in that

In addition, step c) is performed using a planetary mill equipped with three types of balls having different diameters, wherein the balls are large-diameter balls with a diameter of 10 to 30 mm, and a diameter of 5 to A medium-diameter ball of 20 mm and a small-diameter ball having a diameter of 1 to 10 mm are mixed and provided, and pulverized for 0.1 to 2 hours at a speed of 100 to 800 rpm, and a cocoon in a bowl during step c) It is characterized in that the balls are sequentially introduced and the grinding is performed.

Silk fibroin powder according to the present invention is not recrystallized by hydrolysis or dissolution by enzymes or other drugs during manufacture, but is powdered using only dry mechanical grinding means, without destroying the unique nanostructure of silk. Since it can be maintained as much as possible, it can be applied to various medical technologies such as diagnosis, treatment, biosensor, and non-copyable biotransplantation code.

1 is a view showing after pulverization of the powder mixer during the manufacturing process of the silk fibroin powder according to Example 1.
Figure 2 shows the before (a) and after (b) grinding of the planetary mill during the manufacturing process of the silk fibroin powder according to Example 1.
3 shows before (a) and after (b) grinding of the planetary mill during the manufacturing process of silk fibroin powder according to Example 2.
Figure 4 shows the before (a) and after (b) grinding of the planetary mill during the manufacturing process of the silk fibroin powder according to Example 3.
5 (a) and (b) shows the silk fibroin powder prepared in Example 1.

Hereinafter, a method for producing silk fibroin powder according to the present invention will be described in more detail. However, the embodiments introduced below are provided as examples so that the spirit of the present invention can be sufficiently conveyed to those skilled in the art.

Therefore, the present invention is not limited to the embodiments presented below and may be embodied in other forms, and the embodiments presented below are merely described to clarify the spirit of the present invention, and the present invention is not limited thereto.

At this time, unless there are other definitions in the technical terms and scientific terms used, it has a meaning commonly understood by a person of ordinary skill in the art to which this invention belongs, and in the following description, it may unnecessarily obscure the subject matter of the present invention. A description of possible known functions and configurations will be omitted.

Also, the singular forms used in the specification and appended claims may be intended to include the plural forms unless the context specifically dictates otherwise.

The method for producing silk fibroin powder according to the present invention,

a) a refining step of refining the cocoon by contacting the refining solution to the cocoon;

b) a first pulverizing step of pulverizing the refined cocoon into short fibers using a dry mechanical pulverizing means; and

c) a second grinding step of pulverizing the short fibers into a fine powder having an average particle size of 100 μm or less by pulverizing the short fibers with a dry mechanical grinding means;

can proceed, including

In the present invention, step a) is a refining step of removing unnecessary component sericin by contacting the refining solution with a cocoon.

In general, the liquid silk biosynthesized from the silk glands of silkworms composed of 18 amino acids has a high crystallinity fiber arrangement by the silt of the silkworm, and has an elongation of 18 to 24% at 3.8 to 4.2 g/d. Silk formed from two components of about 75% by weight of fibroin and about 25% by weight of sericin is produced.

Sericin is a representative water-soluble globular protein that forms a gel-like gum and wraps around fibroin, a fiber body. It acts as a bonding agent between the fibroin fibers and the cocoon and the base, and functions as a lubricant when forming fibroin fibers.

In the present invention, the cocoon is not limited to the type as long as it is commonly used for textile or bio use in the art. In the case of Korea, 17 kinds of silkworm incentives are designated for the purpose of cocoon production and educational silkworm production, and in the present invention, all of them can be used. -1, N28, Chuhwa, N74 (fusiform cocoon), Chinese silkworm, European Bagdad (1 Hwaseong), Romogua (1 Hwaseong), tropical SA6 (multiple cocoon), Korean three-sided red chrysanthemum (4 Myeonjam), Seon No. 3 (three-sided sleep), etc. may be included, and two or more of these may be mixed and used.

However, since the weight and thickness of the silk layer, the density of the silk layer, the tensile strength, etc. are different depending on the type of cocoon, it can be selectively applied depending on the conditions of the grinding process described later or the average particle size of the silk powder produced. For example, it is recommended to increase the rotation speed of the impeller or ball in the crushing stage or to take a longer crushing time for varieties such as Seon 3 or three-sided red ginseng that have high cutting strength. The particle size of silk particles can be determined by lowering the rotation speed or adjusting the size of the ball.

In the present invention, the electrostatic agent may be used as long as it is a refining agent commonly used when removing sericin from a cocoon. Aqueous alkali aqueous solution which is, for example, aqueous solutions, such as sodium hydroxide, sodium carbonate, calcium carbonate, sodium silicate, sodium phosphate, sodium bicarbonate, borax, ammonia; acidic aqueous solutions, such as lactic acid, tartaric acid, citric acid, oxalic acid, malonic acid, succinic acid, acetic acid, chloroacetic acid, dichloroacetic acid and trichloroacetic acid; Enzyme aqueous solution which is an aqueous solution, such as trypsin (Trypsin) and papain (Papain); and an amine aqueous solution containing amines such as methyl amine and ethyl amine, in addition to tallow oil, olive oil, coconut oil, caster oil, arachis oil Arachis oil, Cotton seed oil, Chrysalis oil, Sodium Laurate, Sodium Myristate, Sodium Stearate, Sodium Arachidate (Sodium Arachidate), Sodium Oleate (Sodium Oleate), Sodium Ricinoleate (Sodium Ricinoleate), etc. surfactants dissolved in water may be used.

The bath ratio of silk to the scouring bath containing the scouring agent (Bath ratio, w/v, g/mL) is preferably 1:5 to 100 by volume of silk:scouring bath. When the bath ratio is less than the above range, the scouring solution is not sufficiently immersed in the silk, so that the removal of sericin is not performed efficiently.

Step a) may be performed by contacting the refining solution set at 50 to 200° C. for 0.1 to 5 hours. Only fibroin can be effectively obtained without damage through the refining process, and when the process is performed below the above temperature or time range, sericin is not sufficiently removed. This can lead to destruction of the nanostructure.

In step a), only the fibroin component may be collected through physical stirring if necessary. At this time, as a physical stirring means, for example, there is an ultrasonic wave, a stirrer, a stirring rod, etc., and the stirring conditions using the same are not limited within the range that does not impair the object of the present invention.

In the present invention, step b) is a first grinding step, and is a process of grinding the refined cocoon into short fibers by a dry mechanical grinding means. In this case, the 'short fiber' is formed by cutting fibroin having the shape of a filament several times, and the length is not limited, but it means having a length of about 5 cm or less.

The pulverizer usable in step b) is not limited to the type as long as it can cut long-fiber fibroin into short fibers through a dry process, for example, an air jet mill, a rotary mill, There are hammer mills, extruder mills, hydraulic crushers, powder mixers, and the like. Among them, an impeller is provided inside so that the fibroin fibers are uniformly mixed while simultaneously grinding and surface modification. It is preferable to use a powder mixer that can achieve

In the present invention, the shape and configuration of the powder mixer is not limited in the present invention, but basically, as in Korean Patent Registration No. 10-1276352, a main body to be pulverized and a blade rotatably mounted inside the main body and bent in cross section It may include an impeller having and a motor rotating the impeller.

At this time, an opening is formed on the upper side of the main body, and a lid for opening and closing the opening is mounted at one end of the opening to prevent short fibers from escaping out of the main body when the fibroin is pulverized, and the impeller is a bottom surface of the inner surface of the main body. It is preferable to be rotatably mounted to the.

The impeller may include a boss coupled to the rotation shaft and a plurality of blades formed on an outer surface of the boss, and one or two or more of the above impellers may be provided as necessary.

In addition, it is preferable to accommodate the ceramic beads together in the body in order to facilitate the grinding of the fibroin fibers separately from the impeller and to shorten the diameter (fineness) or length of the pulverized fibroin fibers. The ceramic beads cause friction with the fibroin fibers while being moved by the impeller, resulting in a shorter length or fineness of the fibers.

The boss is rotatably mounted on the bottom surface of the main body, and can move up and down inside the main body in the axial direction at the same time as the rotation if necessary. The boss may be formed with an insertion hole into which a shaft for rotation is inserted in the center, and is moved by receiving rotational force by the above-described motor.

The wings are disposed on the outer circumferential surface of the boss radially to each other in the direction of the inner circumferential surface of the main body, and may be attached to be inclined at a predetermined angle. In this case, it is preferable that the blade has a long rectangular shape in one direction and a blade portion formed in the shape of a blade for cutting the fibroin fiber is provided at the end.

The motor rotates the rotation shaft to transmit rotation to the impeller, and it is preferable to maintain a high number of rotations in order to shorten the fibroin fiber formation and grinding time. Specifically, the motor preferably rotates the shaft so that the revolution speed of the impeller is 10 to 50 rpm, and the grinding speed (rotation speed, rotation) of the cocoon is 1,000 to 15,000 rpm.

In addition, the powder mixer may further include a rotating means for rotating the main body as described in Korean Patent Registration No. 10-0935688. The rotation means increases the number of contact between the impeller and the fibroin fiber while moving up, down, left and right in addition to the movement of the fibroin fiber by the impeller by revolving the body itself, and at the same time the cut short fiber type fibroin fiber is laminated on the bottom of the body It is possible to prevent further cuts from being made.

In step b), as described above, the impeller is rotated by driving the motor to induce cutting of the fibroin fiber, but the revolving speed of the impeller is 10 to 50 rpm, and the grinding speed of the cocoon is preferably maintained at 1,000 to 15,000 rpm. do. When it is driven below the above range, the second crushing, which will be described later, is not properly performed because the fiber length becomes longer. In addition, it is preferable that step b) proceeds for 1 to 5 minutes.

Next, as in step c), a second grinding step of pulverizing the short fibroin fibers into a fine powder having an average particle size of 100 μm or less by pulverizing the fibroin short fibers with a dry mechanical pulverizing means may be performed.

In the present invention, step c) is a process for producing a fine powder form by pulverizing the fibroin fibers in the form of short fibers with a mechanical grinding means. In this case, the 'fine powder' means that the fibroin in the form of short fibers is completely abraded to form particles having a very small diameter, and the particle size is not limited, but it means having a diameter of about 100 μm or less.

The pulverizer usable in step c) is not limited to the type as long as it can cut long-fiber fibroin into short fibers through a dry process similar to step b), for example, an air jet mill, There are rotary mills, hammer mills, extruder mills, hydraulic crushers, powder mixers, planetary mills, etc. It is preferable to use a planetary mill capable of inducing grinding and abrasion of the fibroin powder.

The planetary mill is a device manufactured to simultaneously revolve and rotate at high speed, has one or more bowls, and is provided so that the bowl is fixed on a circular rotating plate. At the same time as the rotating plate rotates, the bowl is each independently configured to rotate in the opposite direction to the rotating direction of the rotating plate. It uses the principle of pulverization-dispersion by

When the rotating plate and the bowl rotate, the first centrifugal force due to the revolution of the bowl and the second centrifugal force due to the rotation of the bowl act on the ball injected into the bowl. The first centrifugal force acts in a direction away from the axis of rotation of the rotating plate, which is the orbital axis of the ball, and the second centrifugal force, acts in a direction away from the axis of rotation of the bowl, which is the axis of rotation of the ball. The magnitude and action direction of the first centrifugal force and the second centrifugal force vary depending on the position of the ball mill ball.

In addition, when the bowl rotates while the rotating plate rotates, the ball rotates in the same direction as the bowl due to the frictional force between the ball and the bowl wall. Due to the action of these forces, the balls inside the bowl collide with other balls, especially balls of different diameters, short fibroin fibers or the inner wall of the bowl, or in the state of contact with other balls, short fibroin fibers or the inner wall of the bowl. A frictional motion by the rotation of the corresponding ball, that is, a motion applying a mechanical shear force is performed.

According to the rotational speed of the rotating plate and the bowl, the ball inside the bowl undergoes various motions by the action of the above-mentioned forces. Specifically, when the rotational speed of the bowl is gradually increased while rotating the bowl in a state in which the rotating plate rotates at a constant speed, the inner balls perform different motions according to the rotational speed of the bowl.

For example, it referred to the speed (revolution speed) of the spindle V _2, and when the speed (rotation speed) of the bowl hayeoteul as V _1, the case of V _2> V _1, a first centrifugal force due to revolution of the bowl is larger in view In this way, the ball rotates about the orbital axis at the point located farthest from the orbital axis in the inner space of the bowl. In this case, since the inner wall of the bowl applies a frictional force to the ball by the rotation of the bowl, the ball rotates by itself.

When the speed of the rotary plate has a range having a lower limit and an upper limit, if the speed of the bowl is included in the above range, the first centrifugal force due to the revolution of the bowl and the second centrifugal force due to the rotation of the bowl interact to cause the ball to occupy the space inside the bowl. It moves and collides with the wall of the bowl.

When V ₂ < V ₁ , the second centrifugal force due to the rotation of the bowl acts greatly, and the ball rotates about the rotation axis while in contact with the wall surface of the bowl. In this case, the distance between the inner wall of the bowl and the ball is reduced, and the pressure applied to the short fibroin fibers naturally located therebetween increases.

Therefore, it is preferable to control the speed of the bowl and the rotating plate so that the ball can perform frictional motion by the first centrifugal force. That is, at least, when the first centrifugal force acting on the ball located closest to the orbital axis among the balls located in the inner space of the bowl becomes greater than the second centrifugal force, a mechanical shear force is applied to the short fibroin fibers, so that the particle size of the powder becomes uniform and the yield is also increased do.

To this end, in step c), it is preferable to pulverize the pulverized fibroin fibers at a speed of 100 to 800 rpm for 0.1 to 2 hours to adjust the particle size of the pulverized fibroin fibers to 100 μm or less. If it is out of the above range, the particle size may exceed 100 μm or the particle size may not be uniform, and the yield of the powder may be reduced. In addition, during the grinding process as described above, in order to prevent excessive oxidation of the fibroin powder, it is preferable to maintain the inside of the bowl in an inert gas atmosphere during the process.

In addition, the mechanical shear force as described above is also affected by the revolving speed of the bowl, and as the revolving speed increases, the number of times the ball comes into contact with the inner wall of the bowl increases. can get angry However, as described above, if the orbital speed of the bowl becomes too fast, the ball inside the bowl does not rotate and comes into contact with the inner wall, so it is preferable to adjust the orbital speed of the bowl to a certain range.

More specifically, it is preferable to adjust the rotational speed of the rotary plate and the bowl in a specific range, and it is preferable that 0.3 ≤ V ₂ /V ₁ ≤ 0.6. That is, when the ratio of the grinding speed to the revolution speed exceeds the above range, the centrifugal force due to the rotation of the bowl increases and the ball mainly comes into contact with the inner wall of the bowl, so that the rotational force of the ball is not properly transmitted to the fibroin short fibers, and less than the above range In this case, the rotational speed of the ball itself is low, so the rotational force of the ball applied to the short fibroin fiber may be too small.

In the present invention, the ball inserted into the bowl is a spherical object having an overall round shape as in the term, meaning excluding angular shapes such as plate shape, and does not mean a perfect spherical shape, but an oval or its It may also include a spherical shape with some dents.

Preferably, the ball is basically formed of ceramic particles. Examples of such ceramic particles include agate, alumina, aluminum nitride, silica, titanium oxide, zirconia, and the like, and these may be used alone or in combination of two or more.

In addition, the ball is not limited in diameter, but preferably has a diameter of 1 to 50 mm, and all balls having the same diameter may be applied, but three types of balls having different diameters are mixed and the It is preferably located inside the bowl. In this case, it is preferable that the ball is provided with a mixture of a large-diameter ball having a diameter of 10 to 30 mm, a medium-diameter ball having a diameter of 5 to 20 mm, and a small-diameter ball having a diameter of 1 to 10 mm.

As described above, taking various sizes of the balls generally increases the force applied to the balls as the number of rotations increases. This is because the fibers can be cut easily.

However, if the diameter of the ball is large, since the size of the bowl must be relatively large, the energy for applying the rotation may be excessively consumed. In particular, when the critical rotation speed is exceeded, the impact energy and crushing speed increase as the ball rotates along the bowl and the rotation speed of the ball increases to the same as the rotation speed of the bowl. Since it cannot be done, a ball with a small diameter is put together to increase the number of contact between the fibroin fiber and the ball.

The balls are preferably 1 to 5 large-diameter balls, 10 to 50 medium-diameter balls, and 100 to 1,000 small-diameter balls per bowl. If it is out of the above range, the proper ratio between the fibroin fibers and the balls is exceeded, so that the particle size of the powder is different or the grinding effect is not performed properly, and the grinding effect may be deteriorated.

Here, step c) is characterized in that the cocoon and the ball are sequentially put into a bowl and pulverized. That is, after putting the short fibroin fibers into the bowl first and placing them on the bottom surface, the balls having the three sizes of diameters are first uniformly mixed as described above, and then put into the bowl to make the balls on the short fibroin fibers. to place it. When the ball is placed on the short fibroin fibers as described above, the diameter of the fibroin powder becomes uniform to 100 μm or less, and a yield of 90% or more can be achieved.

To explain this in more detail, it is important to apply a mechanical shear force to the short fibroin fibers when performing planetary mill grinding as described above. In order to compress the fibers as much as possible, it is preferable to put the short fibroin fibers into the bowl as described above and then put the balls on them. Due to the difference, the short fibroin fibers first move toward the top surface of the bowl and the ball is located below it, so the mechanical shear force is hardly transmitted to the short fibroin fibers, and the powder diameter becomes irregular and the yield decreases.

The fibroin powder produced through the above process may be further subjected to post-treatment if necessary. In particular, since ceramic powder may be generated together during milling by a ball as described above, it is preferable to obtain only pure fibroin powder by removing large-diameter particles or heavy ball powder through a method such as centrifugation.

Silk fibroin powder according to the present invention is not recrystallized by hydrolysis or dissolution by enzymes or other drugs during manufacture, but is powdered using only dry mechanical grinding means, without destroying the unique nanostructure of silk. Since it can be maintained as much as possible, it can be applied to various medical technologies such as diagnosis, treatment, biosensor, and non-copyable biotransplantation code.

Hereinafter, a method for producing silk fibroin powder according to the present invention will be described in more detail by way of example. However, the following examples are only examples for explaining the present invention in more detail, and the present invention is not limited to the following examples.

(Specification)

Specifications of cocoons, mixers and balls used in Examples are shown in Table 1 below.

[Table 1]

(Example 1)

First, the cocoon was dissolved with sodium carbonate 5g/ℓ, put into a scouring solution having a temperature of 80°C, and the liquid ratio was 3: 100 by volume, soaked for 2 hours, washed with water and dried.

Next, the cocoon in the fibroin state was put into the powder mixer of Table 1, and the idle speed was set to 15 rpm and the grinding speed was 10,000 rpm, and the mixture was pulverized for 3 minutes. After having a rest period for 1 minute after grinding, grinding was repeated for 3 minutes again, and the grinding was performed 10 times in total to obtain fibroin in a short-fiber state as shown in FIG. 1 .

Next, 3.3 g of the short fibroin fibers and the milling balls of Table 1 were put into the planetary mill, but as shown in FIG. Then, an idle speed of 300 rpm and a grinding speed of 690 rpm were set, and the grinding was performed for 90 minutes. The ratio with the initial fibroin short fibers was calculated by measuring the amount of recovered water from which impurities were removed from the pulverized fibroin powder, and it is shown in Table 2 below.

(Example 2)

When pulverizing the short fibroin fibers with the planetary mill in Example 1, a fibroin powder was prepared in the same manner as in FIG. The yield of the prepared fibroin powder was calculated and shown in Table 2 below.

(Example 3)

In Example 1, when grinding the short fibroin fibers with the planetary mill, half of the milling balls were first put into the bowl as shown in FIG. and fibroin powder was prepared in the same way. The yield of the prepared fibroin powder was calculated and shown in Table 2 below.

[Table 2]

As shown in Table 2 above, in the method for producing fibroin powder according to the present invention, a powder yield of up to 90% could be secured by going through a two-step dry grinding process of a powder mixer and a planetary mill. However, it can be seen that the particle size uniformity and yield of the fibroin powder were affected according to the order of input of the milling balls and the fibroin short fibers when grinding the short fibroin fibers using the planetary mill. In particular, the milling balls were put into the bowl first In the case of Example 2, the pulverization of the fibroin short fibers did not proceed properly, so that a large amount of impurities were generated, and it was confirmed that the yield was also very low at 50%.

The above description is merely illustrative of the present invention, and various modifications will be possible without departing from the technical spirit of the present invention by those of ordinary skill in the art to which the present invention pertains, The examples do not limit the present invention. The scope of the present invention should be interpreted by the following claims, and all technologies within the scope equivalent thereto should be construed as being included in the scope of the present invention.

Claims (7)

a) a refining step of refining the cocoon by contacting the refining solution to the cocoon;
b) a first pulverizing step of pulverizing the refined cocoon into short fibers using a dry mechanical pulverizing means; and
c) a planetary mill comprising a ball in which the short fibers are mixed with a large-diameter ball having a diameter of 10 to 30 mm, a medium-diameter ball having a diameter of 5 to 20 mm, and a small-diameter ball having a diameter of 1 to 10 mm a second grinding step of grinding into fine powders having an average particle size of 100 μm or less by grinding for 0.1 to 2 hours at a speed of 100 to 500 rpm using
includes,
Step c) is a method for producing silk fibroin powder, characterized in that the cocoon and the ball are sequentially put into a bowl and pulverized.
The method of claim 1,
The step a) is performed by contacting the cocoon with any one or a plurality of scouring solutions selected from an aqueous alkali solution, an acid solution, an enzyme solution and an amine solution set at 50 to 200° C. for 0.1 to 5 hours. Silk, characterized in that Fibroin powder manufacturing method.
3. The method of claim 2,
Step b) is a method for producing silk fibroin powder, characterized in that it is performed using a powder mixer equipped with an impeller.
4. The method of claim 3,
In step b), the revolution speed of the impeller is 10 to 50 rpm, the grinding speed of the cocoon is 1,000 to 15,000 rpm, and the method for producing silk fibroin powder, characterized in that it is pulverized for 1 to 5 minutes.
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