The aim is to develop reliable HPLC/UV methods for the determination of test item concentration in dose formulations or formulations for special in vitro tests. Selective, accurate, precise and robust methods are developed, which can validated later, and then used for the determination of the concentration of the drug substance in formulations.
Sample preparation methods and HPLC methods are developed in parallel in very short time. Sample preparation methods are kept as simple as possible in order to provide 100% recovery and avoid unnecessary steps to reduce potential error sources. Attention is paid to achieve separation of vehicle components, eventual degradation products or impurities of the test item by the HPLC method. For handling test items showing any chemical instability, light sensitivity etc. additional stabilizing procedures are developed.