A physical mixture of the empty liposomes (800 μL), teriparatide (20 μL, 10 mg/mL) and sucrose (10 μL, 100 mg/mL) was prepared and freeze-dried (dehydration). Peptide loaded liposomes were then obtained by rehydration of the freeze-dried cake. The rehydration procedure was adapted from . Briefly, 20 mM Tris-HCl buffer (pH 7.0) was pre-heated to 55 °C. Initially, the cake was rehydrated with 50 μL of the buffer followed by 30 min incubation at 55 °C. After 30 min, a further 150 μL and then 850 μL of the buffer was added, allowing for a 30 min incubation between each addition. The resulting liposomes were purified by gel filtration (see Section 2.4.1).