Iron MOFs, like aluminium frameworks, are excellent phosphate absorbents and are good candidates for water treatment. Concerning the binding mechanisms of phosphates to iron MOFs, Vargas et al. reported ligand exchange with nonstructural and structural (carboxyl) OH -groups in iron oxide centres. As such, MIL-53(Fe) and MIL-100(Fe) both provides potential binding sites for efficient phosphate absorption. Another mechanism for phosphate retention was demonstrated using MIL-100(Fe). The authors suggested that anion absorption was observed because the resulting -COO-Fe 3+ cluster is Lewis acidic and attracts the electronegative PO4 3- ions. In the case of H2PO4 -binding, electrostatic interactions as well as anion metal coordination were observed. In this study, the immobilization of GUVs to iron MOFs is observed due to electrostatic interactions (supplementary videos SV3, SV4), similar to those seen in the aluminium MOFs. A good yield of GUVs was formed in presence of iron MOFs with both ligands (MIL-53 and MIL-100 (Fe); Figure ). Here, the large number of GUVs produced suggests these MOFs do not hinder vesicle formation. With MIL-53(Fe) we observed small MOF particles as well as MOF clusters that impacted GUV anchoring differently. MIL-53(Fe) clusters immobilized GUVs for extended time duration (Figure ). Whereas there were limited observed instances of GUV anchoring with individual MOF particles. The GUVs with smaller MIL-53(Fe) particles were actively mobile during the imaging process, (Figure ) and showed some reversible interactions with MIL-53(Fe) particles for a few seconds as they were passing by. Such fluidity in the vesicle indicates that membrane rigidity and stability are compromised. Alternatively, multiple GUV@MOFs with MIL-100(Fe) particles were observed and remained stable during imaging (Figure ). The GUV diameters were slightly larger and had broader size distribution with all lipid mixtures compared to MIL-53(Fe) (Figure , S9). We see a similar trend in GUV yield for both iron MOFs as reported with aluminium frameworks indicating large number of vesicles being produced with dicarboxylic acid versus tricarboxylic acid ligands (Figure ).