Impurity Profiles of Active pharmaceutical ingredient
Various international and domestic regulatory authorities such as the United States Food and Drug administration (FDA),the International Conference on Harmonization (ICH) and the Canadian Drug and Health Agency (CDHA) emphasize a lot on identification of impurities and purity standards of Active pharmaceutical ingredient
The various sources of impurity in Active pharmaceutical ingredient are — heavy metals, reagents, ligands, catalysts, filter aids, charcoal, degraded final products obtained during after production of drugs in bulk from different processes like hydrolysis, oxidative degradation, photolytic cleavage, enantiomeric impurity, photolytic cleavage, etc.
The most frequent impurities found in every Active pharmaceutical ingredient are Organic impurities if proper care isn’t taken into consideration throughout the multi-step production process. Manufacturers have to be very careful about these impurities since there is every chance that the residual unreacted materials might remain.
When Active pharmaceutical ingredient are exposed to light during manufacturing process both as a solid or solution, and during packaging, most compounds degrade into solutions when exposed to high intensity UV light. This is termed as Photolytic cleavage impurities
In a chiral drug a single enantiomeric form is now regarded as an improved chemical entity and is expected to offer better results and expected to have lesser side effects. However undesirable enantiomers may creep in and are kept in same category as other impurities
They are mainly derived from manufacturing process in bulk. They mostly include Reagents, ligands , catalysts, heavy metals, filters, etc
In Process Impurities
They can be following:-
- Stereochemistry related impurities- They are mostly enantiomeric impurities formed during production of Active pharmaceutical ingredient
- Crystallization related impurities- Some other material other than the required may crystallize.
- Solvents remain after processing
- Synthetic intermediates and by-products
- Impurities generated during storage
Various guidelines have been set up in regard to dealing with these impurities and it is very important to isolate them to avoid any adverse effect.