摘要：

We developed gas chromatographic-mass spectrometric assays for the enantiomers of 1,2-propanediol, 1,3-butanediol, 1,3-pentanediol, and their corresponding hydroxyacids, lactate, β-hydroxybutyrate, and β-hydroxypentanoate (3-hydroxyvalerate) in biological fluids. The corresponding ketoacids, acetoacetate and β-ketopentanoate, can be assayed simultaneously by pretreating the samples with (NaB 2 H 4 ). The assays involve spiking the samples with deuterated internal standards, deproteinization, ether extraction, and derivatization of the carboxyl groups with ( R , S )-2-butanol/HCl and of the hydroxyl groups with chiral ( S )-(+)-2-phenylbutyryl chloride. Mass spectrometric analysis is conducted under ammonia positive chemical ionization. We used these assays to follow the metabolism of diol enantiomers in dogs. For ( R , S )-1,3-butanediol and ( R , S )-1,3-pentanediol, the uptakes from dog plasma of the R and S enantiomer of each diol were identical. In contrast, the metabolism of ( S )-1,2-propanediol was faster than that of ( R )-1,2-propanediol. ( R )-1,2-Propanediol is formed during acetone metabolism, while ( R , S )-1,3-butanediol and ( R , S )-1,3-pentanediol are potential nutrients. The assays developed will allow further investigations of the metabolism of acetone, ( R )-lactate, and artificial nutrients derived from the 1,3-butanediol and 1,3-pentanediol enantiomers.

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