High-performance liquid chromatography (HPLC) was conducted to quantify the amount of celecoxib in the physical mixtures and in the AMF-exposed tablets. In short, the experiments were performed using a 1260 Infinity HPLC (Agilent Technologies, Inc., USA) on a reverse-phase Luna 5U C18(2) 100 A column (length 150 mm, diameter 4.60 mm; Phenomenex Ltd., Germany). The experiments were performed at room temperature using a mobile phase consisting of 30% Milli Q water and 70% ethanol (>99.7% HPLC grade; VWR). Flow rate was set at 1 mL min -1 and a sample volume of 20 µL injected. UV detection was performed at 251 nm. Celecoxib eluted at about 2.7 min. The physical mixtures and the AMF-exposed tablets were dissolved in ethanol and filtered using a nylon syringe filter Q-max RR 25 mm with a pore size of 0.45 µm (Frisenette Aps, Denmark). Each sample was injected in triplicate (n = 3). The sample mass was corrected for the corresponding water content determined with TGA.