2.5.4. Crystallinity Study Using X-ray Powder Diffraction (XRPD)

For studying the crystallinity of the dried samples, the representative formulae were lyophilized by a freezer dryer (Christ, Alpha2-4LD Plus, Harz, Germany), which are plain GMO-based formulae (F-1-O, F-3-O, F-4-O, and F-5-O), with F-1-O composed of oleic acid as PE and Tween 80 as a stabilizer, while F-3-O, F-4-O, and F-5-O composed of Captex^® 8000 as PE and Tween 80, TPGS, and P407 as the stabilizer, respectively, were subjected to XRPD. The four formulae were compared to a dried PE-free formula composed of GMO and P407 as the lipid and stabilizer, respectively, which are the components of a typical cubic LCN. Cu-ka radiation, a voltage of 40 kV, and a current of 40 mA were used in an X-ray powder diffractometer (Philips, PW 3710, Caerphilly, United Kingdom). From 5° to 50° at 2Ɵ, all measures were implemented at a scan rate of 2°/min.