Date of Award
Master of Science in Chemical Sciences (MSCB)
Dr. Marina Koether
Dr. Chris Dockery
Dr. Michel Van Dyke
The United States Pharmacopeia sets the standards for the manufacturing, storage, and analysis of medicinal formulations. One analysis, dissolution testing evaluates the rate at which the medicinal formulation forms a solution to predict in vivo drug release. Dissolution testing on ibuprofen tablets alone and in the presence of ascorbic acid or caffeine was performed to mimic the administration using orange juice or caffeinated soft drinks to assess their impact on the dissolution rate of ibuprofen. Results using the external calibration method produced a dissolution rate of ibuprofen that decreased 4% in the presence of ascorbic acid and increased 1% in the presence of caffeine. Figures of merit using current calibration methods such as external calibration method, standard addition method, and internal standard method via UV-Vis spectroscopy were performed via the same instrument producing errors from 0.18% to 1.3%. The figures of merit were then compared to a new method that combines the standard addition method and internal standard method first developed in 2015 for elements called standard dilution analysis. This high-risk, high reward attempt used the newly developed standard dilution analysis on complex molecules and Ultra-High-Performance Liquid Chromatography and produced errors from 11% to 15% that were attributed to pump pressure ripples. Biphenyl was then employed to verify the method first using current calibration methods producing errors from 3.4% to 14% and then compared to the standard dilution analysis that produced errors from 0.010% to 17%. The figures of merit were achieved via current calibration methods but due to variables involved with Ultra-High-Performance Liquid Chromatography analysis and the variability of the instrumentation, the standard dilution analysis method failed to be successful for the analysis of ibuprofen.