With the continuous development of formulation technology, povidone, as a non-ionic water-soluble polymer composite pharmaceutical excipient, has been more and more widely used. However, different types of povidone need to be selected for different formulation uses, and there are many technical details in its application that users need to pay special attention to. In this article, the author combines the actual situation of front-line production and explains the precautions for the application of povidone preparations from different angles such as adhesives, coprecipitants, and cosolvents, which has a certain reference significance for users.
The excellent physiological compatibility of the povidone series of pharmaceutical excipients is its inherent unique product characteristic. So far, it has been called the three major synthetic excipients together with cellulose derivatives and acrylic compounds. Use excipients. The povidone series can have a variety of types according to different K values, among which the most widely used varieties are K15, K30 and K90. The Chinese Pharmacopoeia only includes the quality standard of K30, while the British and American Pharmacopoeia includes the overall standards of all povidone K series. As a pharmaceutical excipient, povidone has a variety of dosage forms, and its application details deserve attention.
1. Adhesives
The use of povidone helps to prepare free-flowing compressible particles, and finally produces tablets with strong solubility and good hardness. Povidone K30 is generally used as a binder, and its dosage in tablets is generally 2% to 5%, and its concentration is generally 0.5% to 5%. For loose raw materials, you can choose povidone K90 with strong binding force, and the general dosage is less than 2%. Since povidone is soluble in water and ethanol, the alcohol solution of povidone can be used for water-sensitive, heat-sensitive and volatile granulation, which not only solves the stability problem, but also reduces the drying temperature and shortens the granulation time. Drying time.
The use of povidone as a binder in effervescent tablets requires special attention. Since water is not allowed in the preparation of effervescent tablets, povidone soluble in water and anhydrous ethanol is ideal. Binder. Vinyl pyrrolidone-vinyl acetate copolymer on the market is currently the binder for preparing effervescent tablets, and its dosage is generally 2% to 5%, and the concentration is generally 5% to 10%.
2. Coprecipitate
There are many with good efficacy, but due to low water solubility, the bioavailability is reduced. The carbonyl group in the polyvidone molecule combines with the active hydrogen atom in the poorly soluble molecule through hydrogen bonding, turning the molecule into an amorphous state and entering a completely water-soluble polyvidone macromolecule, thereby inhibiting the formation and growth of the poorly soluble molecule crystals and becoming a supersaturated state, which can greatly improve the solubility of the poorly soluble molecule.
Generally speaking, the dissolution V of the coprecipitates formed by polyvidone with different K values, except for the coprecipitates formed with nifedipine and phenytoin, mostly follows VK15
