Before phage display was attempted, stability tests were conducted to confirm structural integrity of the MONs under incubation conditions. Each system was exposed to phosphate buffer saline (PBS) for 1 h and 24 h and any structural integrity was determined via XRPD. After incubation for 1 h, the XRPD pattern remained unchanged for each system. After 24 h, only small changes were observed for the ZIFs and no change for Hf-BTB-NH2 (Figure -S25). Moreover, AFM studies revealed no significant change in particle size after incubation (Figure ). Selection of Peptide-Functionalized Bacteriophage with High-Affinity MON Binding. Biopanning studies against the three different MON systems were undertaken using genetically modified M13 bacteriophage hosts with a mean length of 880 nm and a mean height of 6.6 nm incorporating a pentavalent display of identical peptides (Figure ). The library of phage-displaying peptides was added to the MONs and incubated for 1 h. Subsequently, a washing step removed any unbound phage, leaving only phage bound to the MONs. The pH of the system was adjusted to enable bound phage elution, which were then amplified through the infection of E. coli. This protocol constituted one panning round. This process was repeated twice by adding the amplified phage from the previous panning round to create increasingly competitive binding conditions and hence identify peptides with the highest affinities. After the third panning round, twelve phage clones were isolated in each case and their DNA was sequenced to determine those peptide sequences that bound with the highest affinity to each MON system.