The design and development of improved fluorocarbon-based products for use in medicine and biology.

Fluorocarbons and other highly fluorinated materials offer considerable potential in diagnosis and therapeutics due to their unique physical properties, chemical inertness, capacity to transport oxygen and drugs, and ability to function as contrast agents. Applications such as hemodilution and organ preservation, cancer diagnosis and chemotherapy, x-ray imaging of the lymph nodes and magnetic resonance imaging of the GI tract, cardioplegia and reperfusion, the treatment of myocardial ischemia and respiratory distress syndrome, as well as drug delivery, all obviously require different product characteristics, calling for an array of products which may range from different neat fluorocarbons to diversely formulated emulsions, or fluorinated vesicles. Substantial progress has been made in terms of emulsion efficacy and stability. Stable, ready-to-use, concentrated, though fluid, injectable emulsions have now been developed. Small doses of such emulsions were demonstrated to be highly efficient in tissue oxygenation. Commercial-scale manufacturing including heat sterilization of these emulsions have been achieved. Some of the side-effects, which generally relate to the normal response of the organism to injected particles, have been reduced, and their mechanism determined. Further efforts will undoubtedly be devoted to understanding and adjusting emulsion properties for optimal efficacy in each identified application and to maximizing benefit vs side-effect ratio. Our ability to modulate in vivo recognition, intravascular persistence and subsequent biodistribution of fluorocarbon droplets, vesicles and other particulate matter in the organism is still in its infancy. Proper control of these characteristics would further extend the potential of such products for medical uses. It is essential that no effort be spared to increase our general understanding of their physicochemical properties and in vivo "physiology".