Validation and Implementation of In-Process Control HPLC Assays for Active Pharmaceutical Ingredients

need to monitor disappearance and formation of reaction components. Such an assay would require adequate resolution of the reaction species, sufficient sensitivity to quantitate the dwindling component, and typically, the ability to accommodate various sample loads. It might not be necessary to start from scratch and set out on a comprehensive method development project, as one might be able to modify an existing release method. Emphasis should be placed on shortening run time, resolution of key components, optimizing sensitivity, and understanding potential interferences by reaction components. Robustness evaluation should be performed as appropriate. An important facet of IPC testing is speed, as the production chemist requires a fast data turnaround. The strategy is to develop an IPC assay that can be performed with just several injections that include blank, standard, and sample. System suitability checks in the assay should be employed to support the expected variability in the IPC sample concentration, and acceptance limits should be based on appropriate method development experiments.