Sample Preparation of Pharmaceutical Dosage Forms

Accurate analytical data is critical in the pharmaceutical industry. During drug development this information is used to evaluate and select formulations for use in toxicology and clinical studies, to assess manufacturing processes and to assess the suitability and stability of clinical supplies. For marketed products, analytical data is used to assess the suitability and stability of the commercial product.

Development and use of robust analytical methods is critical for the ability to generate accurate analytical data. Sample preparation is an integral part of the analytical method. In a survey conducted by LC-GC1, responses indicated that approximately two-thirds of the time spent testing and analyzing samples was spent on the sample preparation portion of the method. In addition, issues related to sample preparation accounted for one-third of the errors generated while performing an analytical method.

A number of challenges exist in the sample preparation/extraction of pharmaceutical dosage forms for potency and purity analysis as well as isolation and identification of impurities and degradants. These challenges increase for complex dosage forms such as some controlled release formulations and other challenging formulations such as suspensions, ointments, transdermal patches, etc. Challenges in developing rapid and rugged sample preparation methods include complete dispersion of the dosage form to facilitate extraction and solubilization of the analytes of interest, dealing with extracted interfering components and addressing drug-excipient interactions. A number of factors must be considered and addressed in each of these areas.

The objective of Sample Preparation of Pharmaceutical Dosage Forms is to provide an overview of the various sample preparation and extraction techniques available for pharmaceutical dosage forms. In addition to the review and discussion of specific techniques, sample preparation method development and trouble shooting strategies are discussed. Multiple examples and case studies are presented to highlight various potential issues and solutions.