Residual solvents in drugs are organic volatile that are used or produced in the manufacturing of active substances or excipients, or in the preparation of medicinal products. Because these chemical residues may be hazardous to human health and to the environment, the drug manufacturer must ensure that they are either not present in their products or are present only below acceptable levels.
The United States Pharmacopeia (USP) general chapter <467> has provided a method for the determination of Class 1 and 2 residual solvents.
In detail, the USP <467> method consists of a static headspace extraction coupled with a gas chromatographic separation and flame ionization.
The method consists of three procedures (A, B, and C) that are designed respectively to identify, confirm, and then quantify residual solvents in drug substances and products.
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