1. Evaluation of internal standard responses during chromatographic bioanalysis: questions and answers Publication: Silver Spring, MD : Center for Drug Evaluation and Research, September 2019 Subject(s): Chromatography -- standardsDrug ApprovalQuality ControlReference StandardsCalibrationChemistry Techniques, AnalyticalInvestigational New Drug ApplicationHumansUnited StatesUnited States. Department of Health and Human Services.United States. Food and Drug Administration.