Cucurbiturils in Oxygen Delivery and Their Potential in Anemia Management

Efficient oxygen transport and accurate anemia diagnostics remain significant medical challenges, as current therapies suffer from stability limitations, immunogenic risks, and inadequate sensitivity. Cucurbiturils (CB[n]), a family of pumpkin-shaped supramolecular macrocycles, present promising solutions due to their rigid architecture, hydrophobic cavities, and strong host–guest binding properties. Functional derivatives such as perhydroxy-cucurbit[5]uril can reversibly bind dioxygen under physiological conditions, highlighting their potential as synthetic hemoglobin substitutes. Additionally, cucurbituril-based probes for Fe3+ and folate enable sensitive and selective detection of iron- and folate-deficiency anemia. Biocompatibility assessments in vitro and in vivo indicate low systemic toxicity and acceptable hemocompatibility for homologues such as CB[6], CB[7], and CB[8], though apoptosis, myotoxicity, or cardiotoxicity may occur at elevated concentrations. These data emphasize the need for thorough toxicological evaluation but also demonstrate that cucurbiturils provide a versatile platform for oxygen transport, diagnostic applications, and drug-delivery strategies in anemia management. While their translation to clinical practice is still at an early stage, the structural tunability, stability, and encouraging safety profile of CB[n] macrocycles offer a strong basis for continued biomedical development.