Synthetic Blood Substitutes

Dozens of compounds have been used in in vivo fluonne NMR and MRI studies, chosen more for their commercial availability and established biochemistry than for ease of fluonne signal detection [244] Among the more common of these are halothane and other fluormated anesthetics [245, 246], fluorodeoxyglucose [242 243], and perfluormated synthetic blood substitutes, such as Fluosol [246], a mixture of perfluorotnpropylamine and perfluorodecahn Results have been Imut-ed by chemical shift effects (multiple signals spread over a wide spectral range) and long acquisition times... 

Polyfvinyl pyrrolidone), prepared from iV-vinylpyrrolidone, is used both in cosmetics and as a synthetic blood substitute. Draw a representative segment of the polymer. 

Kobayashi K, Tsuchida E, Nishide H. Totally synthetic hemes their characteristics and oxygen carrying capacity in dogs. In Tsuchida E, ed. Artificial Red Cells Materials, Performances and Clinical Study as Blood Substitutes. Chichester, England John Wiley Sons Ltd., 1995 93. 

Some of the reactions of NO in the blood do not cause problems at low concentrations, but can upset the normal reactions of hemoglobin if there is a large concentration of NO. The same reactions can cause trouble if a synthetic blood substitute contains a molecule similar to hemoglobin, but does not contain all the other enzymes normally contained in red blood cells. Explain what this problem is and how it arises. 

Emulsions and foams occur ubiquitously in food products. Milk, butter, margarines, sauces, and soups are examples of emulsions. Foamy foods are whipped cream, mousse, milkshake, bread, and so on. In pharmaceutical and cosmetic ointments, lotions, and creams, water-insoluble active components are often supplied as emulsions. An advanced application is that of emulsified fluorocarbons as a blood substitute. It goes without saying that alimentary and biomedical emulsions and foams should be qualified as safe. For these products, proteins rather than synthetic substances are often used as stabilizers. 

There are differences and similarities between the two categories of blood substitutes. Hemoglobin or synthetic metal chelates combine oxygen chemically. 

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