A stepwise ligand exchange strategy is utilized to prepare a series of isoreticular bio-MOF-100 analogues. Specifically, in situ ligand exchange with progressively longer dicarboxylate linkers is performed on single crystalline starting materials to synthesize products with progressively larger mesoporous cavities. The new members of this series of materials, bio-MOFs 101-103, each exhibit permanent mesoporosity and pore sizes ranging from similar to 2.1-2.9 nm and surface areas ranging from 2704 to 4410 m(2)/g. The pore volume for bio-MOF 101 is 2.83 cc/g. Bio-MOF-102 and 103 have pore volumes of 4.36 and 4.13 cc/g, respectively. Collectively, these data establish this unique family of MOFs as one of the most porous reported to date.