A method for preparing high-transmittance hydroxypropylmethylcellulose hollow capsules

Abstract

The present application provides a method for preparing a highly light-transmitting hollow hydroxypropyl methylcellulose capsule, which belongs to the technical field of capsule preparation. After adding cellulose powder to 90-95°C water and mixing evenly, the mixture is cooled to 30-60°C, cellulase is first added for primary dissolution, and hydrogen peroxide is added for secondary dissolution, and the dissolved solution is filtered to obtain a hydroxypropyl methylcellulose solution; the hydroxypropyl methylcellulose solution, carrageenan, potassium chloride and pigment are mixed evenly, heated to 55-65°C while stirring, kept warm for 1-3 hours, cooled to 35-50°C, left to stand, and after dipping in glue at 40-50°C, dried, post-processed, and a capsule product is obtained. The capsule obtained by the method of the present application has high light transmittance and high surface smoothness.

Description

Technical Field

[0001] The present application relates to a method for preparing a high-transmittance hydroxypropylmethylcellulose hollow capsule, belonging to the technical field of capsule preparations. Background Art

[0002] Hydroxypropyl methylcellulose is a common raw material for capsule preparations. However, in the preparation process, insoluble cellulose is usually introduced into the capsule structure. Especially for hollow capsules, the presence of these insoluble substances leads to very low light transmittance of the capsules, especially hollow capsules, which is almost only around 30%, which is not conducive to the observation of the powder in the capsule. At the same time, the presence of the above-mentioned insoluble substances will also affect the smoothness of the capsule surface, and the oral sensory effect is poor. Summary of the invention

[0003] In view of this, the present application provides a method for preparing high-transmittance hydroxypropyl methylcellulose hollow capsules, which imparts high light transmittance and high surface smoothness to the hollow capsules.

[0004] Specifically, the present application is implemented through the following scheme:

[0005] A method for preparing high-transmittance hydroxypropylmethylcellulose hollow capsules comprises the following steps:

[0006] (1) Preparation of hydroxypropyl methylcellulose solution: Add cellulose powder to 90-95°C water and mix well, then cool to 30-60°C, add cellulase for primary dissolution, then add hydrogen peroxide for secondary dissolution, filter the solution to obtain hydroxypropyl methylcellulose solution;

[0007] (2) Preparation of glue solution: Mix hydroxypropyl methylcellulose solution, carrageenan, potassium chloride and pigment evenly, heat to 55-65° C. while stirring, keep warm for 1-3 hours, cool to 35-50° C., and let stand;

[0008] (3) After dipping in glue at 40-50°C, drying and post-processing are performed to obtain a capsule product.

[0009] In the above scheme, cellulose is degraded by combining cellulase with hydrogen peroxide, so that large molecular cellulose is degraded into small molecules, and then insoluble cellulose is removed by filtration, which effectively reduces the content of insoluble matter in the glue solution, significantly improves the uniformity of the glue solution, and correspondingly improves the transparency of the cellulose capsule, and the light transmittance of the cellulose capsule is increased from 30% to 60-75%; at the same time, from the appearance point of view, the surface smoothness of the cellulose capsule is also significantly improved, from Ra10 to Ra1.0-2.0, because the insoluble fiber is reduced, the capsule surface is smoother, and the cellulose capsule looks more transparent as a whole.

[0010] Further, as a preference:

[0011] The cellulose powder is added in an amount of 15-30% (relative to the amount of water added, to form a 15-30% solution).

[0012] The addition amount of the cellulase is 0.01-0.1% (relative to the addition amount of the cellulose powder), the pH is 6-8, and the reaction is carried out at 30-60° C. for 1-10 hours.

[0013] The amount of hydrogen peroxide added is 1-5% (relative to the amount of cellulose powder added), and the reaction is carried out at 30-50° C. for 1-5 hours.

[0014] The above method realizes the preparation of cellulose capsules with high light transmittance and high smoothness.

[0015] The capsule product prepared by the above method is a high-transmittance hydroxypropyl methylcellulose hollow capsule, and its components are as follows:

[0016]

[0017] The hydroxypropyl methylcellulose hollow capsules of the above formula not only have high light transmittance, but also have very good surface smoothness. DETAILED DESCRIPTION

[0018] Example 1

[0019] The preparation method of the high light-transmittance hydroxypropylmethylcellulose hollow capsules of this embodiment comprises the following steps:

[0020] (1) Preparation of hydroxypropyl methylcellulose solution: add 150 kg of cellulose powder (high viscosity) to 1000 kg of hot water (90° C.), mix well, cool to 60° C., add 1% citric acid to adjust the pH to 6.0, add 0.1 kg of cellulase (neutral cellulase) for primary dissolution, and the dissolution time is 5 h; after the reaction is completed, adjust the temperature to 50° C., add 5 kg of hydrogen peroxide for secondary dissolution for 5 h, and filter the resulting solution to obtain the hydroxypropyl methylcellulose solution;

[0021] (2) Preparation of glue solution: 94 parts by weight of hydroxypropyl methylcellulose solution, 4 parts by weight of carrageenan and 2 parts by weight of potassium chloride were mixed evenly, and heated to 55° C. while stirring. After keeping the temperature for 2 hours, the temperature was lowered to 50° C. and allowed to stand;

[0022] (3) Dipping in glue at 50°C, drying, and post-processing to obtain a capsule product.

[0023] Example 2

[0024] The configuration of this embodiment is the same as that of embodiment 1, except that: in step (1), the hydroxypropyl methylcellulose solution is prepared by adding 150 kg of cellulose powder (high viscosity) to 1000 kg of hot water (90° C.), mixing evenly, cooling to 55° C., adjusting the pH to 7.0 with 1% citric acid, adding 0.1 kg of cellulase (neutral cellulase) for primary dissolution, and the dissolution time is 10 h; after the reaction is completed, adjusting the temperature to 40° C., adding 5 kg of hydrogen peroxide for secondary dissolution for 5 h, and filtering the resulting solution to obtain the hydroxypropyl methylcellulose solution.

[0025] Example 3

[0026] The configuration of this embodiment is the same as that of embodiment 1, except that: in step (1), the hydroxypropyl methylcellulose solution is prepared by adding 150 kg of cellulose powder (high viscosity) to 1000 kg of hot water (90° C.), mixing well, cooling to 40° C., adjusting the pH to 7.0 with 1% citric acid, adding 0.1 kg of cellulase (neutral cellulase) for primary dissolution, and the dissolution time is 10 h; after the reaction is completed, adjusting the temperature to 30° C., adding 5 kg of hydrogen peroxide for secondary dissolution for 5 h, and filtering the resulting solution to obtain the hydroxypropyl methylcellulose solution.

[0027] Example 4

[0028] The configuration of this embodiment is the same as that of embodiment 1, except that: in step (1), the hydroxypropyl methylcellulose solution is prepared by adding 150 kg of cellulose powder (high viscosity) to 1000 kg of hot water (92° C.), mixing well, cooling to 40° C., adjusting the pH to 7.5 with 1% sodium bicarbonate, adding 0.1 kg of cellulase (neutral cellulase) for primary dissolution, and the dissolution time is 10 h; after the reaction is completed, adjusting the temperature to 30° C., adding 5 kg of hydrogen peroxide for secondary dissolution for 5 h, and filtering the resulting solution to obtain the hydroxypropyl methylcellulose solution.

[0029] Example 5

[0030] The configuration of this embodiment is the same as that of embodiment 1, except that: in step (1), the hydroxypropyl methylcellulose solution is prepared by adding 150 kg of cellulose powder (high viscosity) to 1000 kg of hot water (95° C.), mixing well, cooling to 40° C., adjusting the pH to 8.0 with 1% sodium bicarbonate, adding 0.1 kg of cellulase (neutral cellulase) for primary dissolution, and the dissolution time is 10 h; after the reaction is completed, adjusting the temperature to 30° C., adding 5 kg of hydrogen peroxide for secondary dissolution for 5 h, and filtering the resulting solution to obtain the hydroxypropyl methylcellulose solution.

[0031] Example 6

[0032] The configuration of this embodiment is the same as that of embodiment 1, except that in step (1), 200 kg of cellulose powder, 0.12 kg of cellulase, and 6.5 kg of hydrogen peroxide are added to every 1000 kg of hot water (90° C.).

[0033] Example 7

[0034] The configuration of this embodiment is the same as that of embodiment 1, except that in step (1), 300 kg of cellulose powder, 0.15 kg of cellulase, and 7.5 kg of hydrogen peroxide are added to every 1000 kg of hot water (90° C.).

[0035] Example 8

[0036] The configuration of this embodiment is the same as that of embodiment 1, except that in step (2), every 90 parts by mass of hydroxypropyl methylcellulose solution corresponds to: 5 parts by mass of carrageenan, 3 parts by mass of potassium chloride and 2 parts by mass of pigment.

[0037] Example 9

[0038] The configuration of this embodiment is the same as that of embodiment 1, except that in step (2), every 90 parts by mass of hydroxypropyl methylcellulose solution corresponds to: 4 parts by mass of carrageenan, 3 parts by mass of potassium chloride and 3 parts by mass of pigment.

[0039] The hollow capsules prepared in the above examples were tested according to the following test standards:

[0040] (1) Light transmittance: Refer to the light transmittance test method in the 2020 edition of the Chinese Pharmacopoeia

[0041] (2) Surface smoothness: measured using a surface roughness measuring instrument, refer to GB 10610-2009.

[0042] (3) For other relevant data of capsules, please refer to the 2020 edition of the Chinese Pharmacopoeia.

[0043] The test results are shown in Table 1.

[0044] Table 1: Performance comparison table of different embodiments

[0045]

[0046] The blank capsules were prepared as follows:

[0047] (1) Preparation of hydroxypropyl methylcellulose solution: Add 150 kg of cellulose powder (high viscosity) to 1000 kg of hot water (90° C.), mix well, and cool to 60° C. to obtain a hydroxypropyl methylcellulose solution;

[0048] (2) Preparation of glue solution: 94 parts by weight of hydroxypropyl methylcellulose solution, 4 parts by weight of carrageenan and 2 parts by weight of potassium chloride were mixed evenly, and heated to 55° C. while stirring. After keeping the temperature for 2 hours, the temperature was lowered to 50° C. and allowed to stand;

[0049] (3) Dipping in glue at 50°C, drying, and post-processing to obtain a capsule product.

[0050] By comparing the examples with the blanks, it can be seen that the method of the present application can improve the light transmittance of the capsule from 30% to more than 60%, up to 75%, and the surface smoothness is improved from Ra10 to a maximum of Ra1.0, and the smoothness is significantly improved. It can be seen that the method of the present application has a good effect on improving the light transmittance and surface smoothness of the capsule.

[0051] By comparing Example 1 with Examples 2 and 3, it can be seen that as the dissolution temperature decreases, the light transmittance and surface smoothness show a decreasing characteristic. The reason is that lowering the temperature is not conducive to the reaction of hydrogen peroxide and the dissolution of insoluble fibers.

[0052] By comparing Example 1 with Examples 4 and 5, it can be seen that as the pH value increases, the transmittance and surface smoothness show a decreasing characteristic. The reason is that the increase in pH value is not conducive to the reaction of cellulase and the dissolution of insoluble fibers.

[0053] By comparing Example 1 with Examples 6 and 7, it can be seen that as the amount of cellulose powder added increases, the transmittance and surface smoothness show a decreasing characteristic. The reason is that as the cellulose concentration increases, the viscosity of the solution increases accordingly, which is not conducive to the reaction of cellulase and hydrogen peroxide, and is not conducive to the dissolution of insoluble fibers.

[0054] By comparing Example 1 with Examples 8 and 9, it can be seen that with the addition of pigment, the light transmittance and surface smoothness show a downward trend.

[0055] The hydroxypropylmethylcellulose hollow capsules prepared by the above method not only have high light transmittance, but also have very good surface smoothness.

Claims

1. A method for preparing a high-transmittance hydroxypropylmethylcellulose hollow capsule, characterized in that: The following steps are involved: (1) Preparation of Hydroxypropyl Methylcellulose Solution: Add cellulose powder to 90-95°C water and mix well, then cool to 30-60°C, add cellulase for primary dissolution, then add hydrogen peroxide for secondary dissolution, filter the solution to obtain Hydroxypropyl Methylcellulose solution. The amount of cellulose powder added is 15-30%, The cellulase is added in an amount of 0.01-0.1%, the pH is 6-8, and the reaction is carried out at 30-60°C for 1-10 hours; (2) Preparation of glue solution: Mix hydroxypropyl methylcellulose solution, carrageenan, potassium chloride, sunscreen and pigment evenly, heat to 55-65°C while stirring, keep warm for 1-3 hours, cool to 35-50°C, and let stand; (3) After dipping in glue at 40-50°C, drying and post-processing are performed to obtain a capsule product. The components of the obtained capsule product are as follows: Hydroxypropyl methylcellulose: 89-96, Carrageenan: 1-5, Potassium chloride: 0.5-3, Pigment: 0-3.

2. The method for preparing a highly transparent hydroxypropylmethylcellulose hollow capsule according to claim 1, characterized in that: In step (1), the amount of hydrogen peroxide added is 1-5%, and the reaction is carried out at 30-50° C. for 1-5 hours.

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