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The relatively new class of porous material known as metal-organic framework (MOF) exhibits unique features such as high specific surface area, controlled porosity and high chemical stability. Many green synthesis approaches for MOFs have been proposed using biocompatible metal ions and linkers to maximise their use in pharmaceutical fields. The involvement of biomolecules as an organic ligand can act promising because of their biocompatibility. Recently, cyclodextrin metal-organic frameworks (CD-MOFs) represent environmentally friendly and biocompatible characteristics that lead them to biomedical applications. They are regarded as a promising nanocarrier for drug delivery, due to their high specific surface area, high porosity, tuneable chemical structure, and easy fabrication. This review focuses on the unique properties of CD-MOF and the recent advances in methods for the synthesis of these porous structures with emphasis on particle size. Then, the state-of-the-art drug delivery systems with various drugs along with the performance of CD-MOFs as efficient drug delivery systems are presented. Particular emphasis is laid on researches investigating the drug delivery potential of ?-CD-MOF.

We present a rapid and surfactant-free temperature-assisted synthesis route to prepare γ-cyclodextrin-based metal–organic framework (γ-CD-MOF). The cubic crystals of the CD-MOF with an average edge length of 10–15 µm, specific surface area of 775 m2 g−1 and total pore volume of 0.229 cm3 g−1 were synthesized in much shorter time than conventional CD-MOFs. To show the efficiency of the synthesized CD-MOF as adsorbent of gas, the uptake of CO2 at different temperature and pressure was investigated. It is shown that the CO2 uptake increases with increasing pressure and decreasing temperature. Further microgravimetric investigation on gas adsorption at low pressure demonstrated superior gas uptake (ca. 147 mg g−1) than previous reports. At the maximum equilibrium pressure, the uptake amounts of CO2 were found to be 326 and 268 mg g−1 at 303 and 323 K, respectively. The synthesized CD-MOF has great potential to be used in gas storage and separation applications.

Environment-friendly nanosponges, having a high content of carboxyl groups, were synthesized by crosslinking &beta, cyclodextrin and linecaps, a highly soluble pea starch derivative, with citric acid in water. Additionally, pyromellitic nanosponges were prepared by reacting &beta, cyclodextrin and linecaps with pyromellitic dianhydride in dimethyl sulfoxide and used in comparison with the citric nanosponges. After ion-exchange of the carboxyl groups H+ with sodium ions, the ability of the nanosponges to sequester heavy metal cations was investigated. At a metal concentration of 500 ppm, the pyromellitate nanosponges exhibited a higher retention capacity than the citrate nanosponges. At lower metal concentrations (&le, 50 ppm) both the citrate and the pyromellitate nanosponges showed high retention capacities (up to 94% of the total amount of metal), while, in the presence of interfering sea water salts, the citrate nanosponges were able to selectively adsorb a significantly higher amount of heavy metals than the pyromellitate nanosponges, almost double in the case of Cu2+.