API and Excipients Compatibility Studies

Pharmaceutical excipients are inactive substances added to drug formulations to aid in drug delivery, stability, or palatability, and play an important role in drug release, drug stability, and drug product manufacturing. Protheragen-ING provides specialized services to study the compatibility between the Active Pharmaceutical Ingredient (API) and its excipients used in its formulation, helping to assess any potential interactions between the two that may affect the quality of the drug, stability, efficacy, or safety of the drug.

Fig.1 API and Excipients Compatibility Studies.

Why Need Compatibility Studies?

Although excipients are considered inert, they can have a significant impact on drug stability because they can interact with the API to chemically react/degrade it. Reasons for this may include the activation of functional groups present in the excipient and its impurities in the presence of light, heat, and moisture during storage.

For example, the presence of reducing sugar impurities in excipients containing reducing sugars (e.g., lactose, maltose, dextrose) or in excipients such as microcrystalline cellulose can facilitate the Meladic reaction of drugs containing primary and secondary amines.

API-Excipient Compatibility Study Services

Protheragen-ING performs formulation screening studies with as little as a few milligrams of API. When only low milligram amounts are synthesized and/or purified, these methods can be used to formulate new drugs for initial in vivo experiments. Some of our offerings include:

Types of Incompatibilities We Study

Physical Incompatibility We study the physical changes or interactions that may occur between the API and excipients. For example, the API and excipients may precipitate, phase separate, or form particles during mixing, which may lead to physical stability issues with the formulation, such as drug precipitation, inhomogeneous suspensions, or inconsistent drug release.
Chemical Incompatibility The study of possible chemical reactions between the API and excipients such as acid-base, oxidation, and reduction reactions, which may lead to degradation of the drug, undesirable side effects, or the formation of harmful impurities.
Solubility Incompatibility The solubility of the drug and excipients may not match, resulting in incomplete dissolution of the drug in the formulation or the formation of precipitates. This may affect the bioavailability, absorption properties, and efficacy of the drug.
pH Incompatibility Certain drugs may degrade or undergo chemical changes at specific pH conditions, thereby reducing the potency and stability of the formulation.
Light-sensitive Incompatibility Certain drugs and excipients are light-sensitive and may be chemically altered or degraded by light exposure, resulting in impaired quality and stability of the drug.

Our API Excipient Compatibility Methods

Fig.2 DSC is used for amorphous and semi-crystalline polymer analysis.

If you are interested in this service and need more information, contact us and we will arrange for professionals to provide you with more information and discuss your specific requirements.


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