The contour plots for Zn0.5Fe2.5O4 and Mn0.5Fe2.5O4 (Figure ) show the extent of drug amorphization as a function of AMF exposure time, drug load and SPION content. Red areas in the contour plot illustrate process conditions that achieved >90% degree of amorphization. Mn0.5Fe2.5O4 was more effective than Zn0.5Fe2.5O4 in formation of completely amorphous ASDs. This can be attributed to the better heating efficiency of Mn0.5Fe2.5O4 (Figure ), resulting in higher tablet temperatures and faster dissolution of celecoxib into the PVP network. The SPION content also positively affected the degree of drug amorphization with no significant quadratic term, indicating a linear effect of this parameter in the entire design space. However, the SPION content showed a significant interaction term with the SPION composition. In contrast, the tablet drug load had a negative influence on drug amorphization. Thus, the tablets with 50 wt% drug load showed a lower degree of amorphization compared to 30 wt% at similar exposure times and temperatures. This follows the Noyes-Whitney equation that predicts that for a higher drug load, a higher Tmax can result in complete dissolution in a solvent, here the polymer. Higher temperatures increase the saturation solubility of the drug in the polymer, lower the viscosity of the continuous (polymer) phase, and increase the diffusion coefficient according to the Stokes-Einstein equation. This in turn results in a faster dissolution rate. In fact, for tablets 27 and 28 with a high SPION concentration of 20 wt% (Table ), celecoxib was not completely amorphized, even though temperatures reached above the onset temperature of dissolution. This could have been a result of the high drug load (50 wt%) that might require longer exposure times (>15 minutes) than applied here to result in complete drug amorphization, since dissolution is a time and temperature dependent process. It should be noted that at high drug loads, the drug becomes the bulk of the tablet, resulting in incomplete dissolution of the drug into the polymer also due to insufficient polymer content.