FT-IR spectrum of (a) F3 formulation loaded with MUP. Inset: SA, PPG and F3 unloaded materials, (b) F4 formulation loaded with MUP. Inset: CS, SA, Gly and F4 unloaded materials and (c) F5 formulation loaded with MUP. Inset: CS, SA, PPG and F5 unloaded materials.