Sample Preparation: Aqueous Solution
Aqueous solutions of PVA with a concentration of 5% w/v and 7.5% w/v were prepared by stirring PVA in distilled water using a magnetic stirrer. Distilled water was heated at a temperature of 90°C, and PVA granules were added and stirred for 2 h at 80°C. PHEA at a concentration of 2.5% w/v was added to already made PVA solutions and stirred for 12 h using a magnetic stirrer. Ibuprofen sodium at a level of 10% w/v was then added to PVA and PHEA solution and stirred for 2 h.