Bulk drug during its production process, after its scale up, it is necessary to analyse for the presence of any impurities or related substances in it. This is to ensure the impurities and related substances are within their limits as per ICH Guidelines. The impurities and related substances are defined as; Impurity: Any component present in the drug substance or drug product which is not the desired product, a product-related substance, or excipient including buffer com...