Shelter for Biologically Relevant Molecules: Photoprotection and Enhanced Thermal Stability of Folic Acid Loaded in a ZIF-8 MOF Porous Host

We hereby propose the use of ZIF-8 MOF (a biocompatible porous material belonging to the zeolitic imidazolate framework subclass) as a host for biologically relevant molecules such as folic acid (PteGlu). It was demonstrated that PteGlu loading can be achieved via a straightforward one-pot encapsulation procedure without compromising the ZIF-8 crystalline structure, given that suitable molar ratios of the metal precursor, linker, and guest molecule are employed. The PteGlugZIF-8 composite thus synthesized brings two novel interesting features: increased thermal stability and a remarkable photoprotection effect of the highly photolabile PteGlu molecule. Both features are very relevant for common uses of PteGlu, such as the production of folate-enriched food.