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Polyhedral molecules are appealing for their eye‐catching architecture and distinctive chemistry. Perfluorination of such, often greatly strained, compounds is a momentous challenge. It drastically changes the electron distribution, structure and properties. Notably, small high‐symmetry perfluoropolyhedranes feature a centrally located, star‐shaped low‐energy unoccupied molecular orbital that can host an extra electron within the polyhedral frame, thus producing a radical anion, without loss of symmetry. This predicted electron‐hosting capacity was definitively established for perfluorocubane, the first perfluorinated Platonic polyhedrane to be isolated pure. Hosting atoms, molecules, or ions in such "cage" structures is, however, all but forthright, if not illusionary, offering no easy access to supramolecular constructs. While adamantane and cubane have fostered numerous applications in materials science, medicine, and biology, specific uses for their perfluorinated counterparts remain to be established. Some aspects of highly fluorinated carbon allotropes, such as fullerenes and graphite, are briefly mentioned for context. [ABSTRACT FROM AUTHOR]

Research has been conducted on the blood substitutes, injectable preparations capable of delivering O (sub)2 to tissues and removing CO (sub)2. Different avenues explored in developing injectable O (sub)2 delivering systems have been summarized and discussed in this review.

The article focuses on a study on the synthesis of perfluorocubane that contributes to the understanding of electron-accepting perfluorinated polyhedral structures, which references a research paper published within the issue. Topics discussed include the challenge in achieving perfluorination, characteristics of perfluorocarbons, and the replacement of the hydrogens with fluorines with the use of fluorine molecules.

The article discusses the research which attempts to collect information on multiple facets of FnHm diblocks. It stresses that the result of the study showed an unexpected antiadhesion phenomenon in which an emulsion prevented the adhesion of cells into tissue culture. It further states that emulsion has proven to be capable of the detachment of adhering cells.

The basic properties of perfluorocarbons (PFCs) and PFC emulsions relevant to their use as oxygen delivery systems are briefly reviewed. The key issues related to the selection of an appropriate, readily excretable PFC and the engineering of a stable injectable PFC emulsion are discussed. OxygentTM, a terminally heat-sterilized, injectable 60% w/v PFC emulsion made primarily of F-octyl bromide and a few percent of F-decyl bromide, with egg phospholipids as an emulsifier, has been developed. Its efficacy in avoiding and reducing red cell transfusion during surgery has been established during a Phase III clinical evaluation. Another Phase III clinical trial in cardiopulmonary bypass surgery, with a protocol that included both augmented-acute normovolemic hemodilution and intraoperative autologous donation, has, however, been interrupted following the observation of adverse events. Data analysis assigned these events to an inappropriate study protocol. A search for possible interactions between Oxygent and fluids present during cardiopulmonary bypass surgery detected no effect of the emulsion on hemostasis, hemolysis and blood rheology. [ABSTRACT FROM AUTHOR]

The unique behavior of perfluorocarbons (PFCs), including their high oxygen dissolving capacity, hydrophobic and lipophobic character, and extreme inertness, derive directly, in a predictable manner, from the electronic structure and spatial requirements of the fluorine atom. Their low water solubility is key to the prolonged in vivo persistence of the now commercially available injectable microbubbles that serve as contrast agents for diagnostic ultrasound imaging. Oxygen TM, a stable, small-sized emulsion of a slightly lipophilic, rapidly excreted PFC, perfluorooctyl bromide (perfiubron), has been engineered. Significant oxygen delivery has been established in animal models and through Phase II and III human clinical trials. However, an inappropriate testing protocol and the lack of funding led to temporary suspension of the trials. [ABSTRACT FROM AUTHOR]

We investigated the effect of a perfluorocarbon emulsion (FC) added to the University of Wisconsin (UW) solution on hypothermic (4° C, 12-72h) preservation of rat small bowel grafts. The FC was 90%w/v perfluorooctylbromide, 2%w/v egg yolk phospholipids and 1.4%w/v mixed fluorocarbon-hydrocarbon molecular dowels. Four groups were defined: [1] UW flush and UW storage; [2] UW flush and FC storage; [3] flush with FC diluted 2 times with UW (FU) and FU storage; [4] FU flush and storage in oxygenated FU. Preservation was estimated with a histological score based on villus epithelium adhesion, on villus sloughing and on crypt cell adhesion to the basal membrane. Antioxidant potential was estimated by measurement of total thiol functions (SH) and activities of glutathione-peroxidase (GSH-P), superoxide dismutase (SOD) and catalase. FC in flush improved preservation during the first 24h (p<0.01). Storage in FC appeared superior to UW for the first 24h (p<0.01). Oxygenation (100% O[SUB2]) of the storage medium yielded superior results at 12h and 24h (p<0.01 and p<0.001 versus group [1] respectively). After 72h, SOD and catalase activities increased in groups [3] and [4], and SOD decreased in group [1] (p<0.05). SH progressively decreased in group [1] (p<0.05) and GSH-P increased at 24 and 48h in groups [3] and [4] (p<0.01). The increase of O[SUB2] in the perfusion flush or storage medium ameliorated the preservation status and protected the antioxidant potential of the small bowel. [ABSTRACT FROM AUTHOR]

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