Metal-organic frameworks (MOFs), with high surface area, play an important role in drug delivery. With perfect biocompatibility and green preparation process, the γ-cyclodextrin metal-organic framework (γ-CD-MOF) fabricated with cyclodextrin and potassium is suitable for antigen delivery. In this study, γ-CD-MOF was modified with span-85 to fabricate the SP-γ-CD-MOF as animal vaccine adjuvants. The ovalbumin (OVA) as the model antigen was encapsulated into particles to investigate the immune response. SP-γ-CD-MOF displayed excellent biocompatibility in vitro and in vivo. After immunization, SP-γ-CD-MOF loaded with OVA could induce high antigen-specific IgG titers and cytokine secretion. Meanwhile, SP-γ-CD-MOF also significantly improved the proliferation of spleen cells and activated and matured the bone marrow dendritic cells (BMDCs). The study showed the potential of SP-γ-CD-MOF in vaccine adjuvants and provided a novel idea for the development of vaccine adjuvants.
The recipe for production of SP-γ-CD-MOF:
γ-CD (648 mg) and KOH (224 mg) were dissolved into a 21 mL mixture solution of pure water and methanol (v/v:20:1). MeOH was allowed to vapor diffuse into the solution. After 6 h, the supernatant was transferred into MeOH with the addition of CTAB, and the solution was incubated 3 h at room temperature. The white cubic crystals were isolated, filtered, and washed with isopropanol three times. The wet sample was then dried in a vacuum oven at 45 °C for 12 . The white powers were collected and named γ-CD-MOF. In order to improve the stability, 100 mg γ-CD-MOF were dispersed into dichloromethane with span-85 for 48 h. Then the precipitates were collected via centrifuge at 8000 rpm for 5 minutes and washed 2–3 times with dichloromethane. The collected powders were SP-γ-CD-MOF.

Li C, Chen C, Wei Y, Tan M, Zhai S, Zhao J, Wang L, Dai T. Cyclodextrin metal-organic framework as vaccine adjuvants enhances immune responses. Drug Deliv. 2021 Dec;28(1):2594-2602. doi: 10.1080/10717544.2021.2012306.