Sources of Impurities in Pharmaceutical Subsstances
The root of impurities in drugs is from various sources and phases of the synthetic process and development of pharmaceutical dosage forms. Bulk of the impurities are characteristics of the synthetic route of the manufacturing process. There are numerous possibilities of synthesizing a drug; it is possible that the identical product of different sources may give growth to different impurities.
According to the ICH impurities are labeled as organic impurities, inorganic impurities and residual solvents.
Organic impurities may result from starting materials, by products, synthetic intermediates and degradation products. Inorganic impurities may be obtained from the manufacturing process and are normally known and identified as reagents, ligands, inorganic salts, heavy metals, catalysts, filter aids and charcoal etc. Residual solvents are the impurities carried with solvents. Of the above three types, the number of inorganic impurities and residual solvents are limited. These are easily distinguished and their physiological effects and toxicity are well known. For this reason the limits set by the pharmacopoeias and the ICH guidelines can guarantee that the harmful outcomes of these impurities do not add to the toxicity or the impacts of the drug substances.
The situation is different with the natural impurities. Drugs prepared by multi-step synthesis results in numerous impurities, their number and the variety of their structures are almost unlimited and highly dependent on the route and reaction conditions of the synthesis and several other factors such as the purity of the starting material, process of isolation, purification, conditions of storage etc. In addition, toxicity is hidden or not easily predictable. For this reason the ICH guidelines set threshold limit above which the identification of the impurity is essential.
(A) Sources of organic impurities:
• Impurities arising from drug substance synthetic processes
• Beginning materials and intermediates
• Impurities in the opening materials
• Reagents, ligands and catalysts
• By-products of the synthesis
• Products of over-reaction
• Products of side reactions
• Impurities arising from degradation of the drug substance.
(B) Enantiomeric impurities:
Most therapeutic chiral drugs utilized as pure enantiomers is natural products. The high level of enantio selectivity of their biosynthesis eliminates the possibility of the presence of enantiomeric impurities. In the case of synthetic chiral drugs, the racemates which are usually sold, if the purified enantiomer is administered, the antipode is an impurity. The reason for its presence can be either the inadequate enantio selectivity of the syntheses or meager resolution of the enantiomers of the racemate. Oceanic Pharmachem Pvt. Ltd. is manufacturer of drug intermediates. At Oceanic Pharmachem Pvt. Ltd. we focus on quality of pharmaceutical intermediates and fine chemicals by regular quality audits. Quality runs across all our departments, extending from early stage development to document control and manufacturing to validation. Irrespective of function, our people are passionate about delivering manufacturing excellence.
Effects of Impurities in Pharmaceuticals
The substance that are used in pharmaceutical field must be clear so that they can be used safely. But it is very difficult to obtain an almost absolute pure substance. Different substance and chemicals have varying grade of purity.
Effect of Impurities:
We know that almost all pure substances are difficult to get, and some amount of impurity is invariably present in the material. So, the impurities that are present in the substances may have the following effects.
• Impurities may bring about conflict with other substances.
• Impurities may lower the shelf life of the substances.
• Impurities may cause complications during formulations and use of the substances.
• Sometimes Impurities alters the physical and chemical properties of the substances.
• Therapeutic effect can be decreased.
• Shows toxic impact after a certain period.
• Injurious when present beyond certain limits.
• It may change odour, colour, taste of the substance.
To prevent these impurities many tests such as limit test are carried out to lower the impurities to ensure the pharmaceuticals safer. At Oceanic Pharmachem Pvt. Ltd. we focus on quality of pharmaceutical intermediates and fine chemicals by regular quality audits. Quality runs across all our departments, varying from initial stage development to document control and manufacturing to validation. Irrespective of purpose, our people are passionate regarding achieving manufacturing excellence.
Oceanic Pharmachem Pvt. Ltd. is one of the foremost manufacturers and exporters of Advanced Pharmaceutical Drug Intermediates.