Due to the use of different materials in vegetarian and hollow gel capsules (gelatin capsules), the identification test method for each is different. This article shows the advantages of vegetable capsules and gel capsules (gelatin capsules) in their application.
The raw materials in vegetable capsules and gel capsules (gelatin capsules)
1. The main component of medicinal vegetable capsules is hydroxypropylmethylcellulose (HPMC), that is, hydroxypropylmethylcellulose. Cellulose is the richest natural polymer in nature’s resources. HPMC is generally derived from cotton linters or wood pulp made by etherification.
2. The main component of high quality pharmaceutical gel capsules is gelatin derived from animal skin, tendon, bone in collagen, a protein from animal connective tissue or collagen from epidermal tissue, partially hydrolyzed.
The test methods of vegetable capsules and gel capsules
The characteristics of vegetarian capsules and gelatin capsules are the same.
The material used in vegetable capsules is hydroxypropylmethylcellulose.
The identification of vegetarian capsules and gel capsules is different.
Inspection checks for vegetarian capsules and gel capsules have the same standard: dry vegetable capsule weightlessness standard is 2%-7% and 12.5%-17% loss on drying standard of the gel capsules. This is due to hydroxypropylmethylcellulose. In the drying of vegetable capsules this standard is from 2% to 7%.
Pharmacopeial Methods for Sample Identification and Preparation
Identify and prepare a sample vegetarian capsule:
(1) To extract 1 g of this product, add 20 to 25 ml of cold water, stirring constantly until the liquid becomes viscous. Add 2 mL to a test tube, pouring the liquid slowly down the inside surface of the test tube.
(2) to extract the correct amount of viscous liquid (1) pour on a glass plate, leave until the water evaporates and forms a resistant film.
Identify and prepare a sample gelatin capsule:
(1) To extract 0.25 g of this product, add 50 ml of water. Heat until dissolved and allow to cool. Add 5 ml more of the potassium dichromate test solution; mix with a few drops of hydrochloric acid solution (4%) to form a flocculent yellow-orange precipitate.
(2) to identify 1 ml of the rest of the solution (1) add 50 ml of water, add a few drops of tannic acid test solution, and shake until cloudy.
(3) put 0 3 g of the product in a test tube. Add a little sodium lime. Heat the gas until a wet red litmus paper turns blue.
Distinction of the dissolution of the two capsules (vegetarian capsules and gelatin capsules)
Soluble in cold water: when the capsules are placed in 25 ml of cold water, the gelatin capsules do not dissolve. Vegetarian capsules dissolve gradually.
Distinguish the two capsules under combustion
During combustion, the vegetable capsule produces a cotton-like odor. The gelatin capsule produces a protein odor similar to the smell of burning hair.