ANALYSIS OF ETHANOL AND ACETALDEHYDE RECOVERY FROM PERCHLORIC ACID-TREATED BLOOD

Recovery of acetaldehyde (0-20 mu M) or ethanol (0-50 mM) added to blo od and subsequently treated with perchloric acid (PCA) was evaluated u sing head-space gas chromatography and compared with controls. Using b lood from five dogs, <100% of acetaldehyde and ethanol was recovered f rom PCA-treated samples. Mathematical models of putative binding mecha nisms indicated acetaldehyde partitioned simply between supernatant an d PCA-induced precipitate and occupied <1% of acetaldehyde binding sit es on precipitate; ethanol partitioned simply between supernatant and precipitate and occupied > 62% of ethanol binding sites. The mathemati cal model also indicated acetaldehyde binding is 2500-fold stronger th an ethanol binding. These results indicate as much as 46.4% of acetald ehyde may be bound to PCA-induced precipitate formed in whole blood. T his loss of acetaldehyde is 3- to 4-fold greater than acetaldehyde los s caused by evaporation from PCA-treated blood.