Analysis of Enantiomers in Plasma and Urine

FIGURE 14.2 Achiral-chiral separation of S-Ketorolac (S-l), R-Ketorolac (R-l), p-hydro-xyketorolac enantiomers (2,3) and internal standard Naproxen (4). (a) Urine blank (b) blank urine spiked with 1.5pg/mL each of racemic ketorolac and p-hydroxyketorolac (c) Nondeconjugated urine sample taken from a patient who received 10 mg of oral racemic ketorolac. Reprinted from Diaz-Perez et al. (1994) with permission from John Wiley Sons. 

Mass spectrometry (MS) is also being used to add another dimension of analysis to achiral-chiral analysis. Recently, an achiral-chiral column-switching LC/LC-MS/MS method was reported for the pindolol enantiomers in human serum (Motoyama et al., 2002) and phenprocoumon metabolites (Kammerer et al., 1998). For analytes that have very poor chromophores or cannot naturally fluoresce, MS detection can be more sensitive for the underivatized form of the analyte. Also, MS detection can be particularly useful when very similar analytes that differ in mass (such as some amino acids and metabolites) cannot be satisfactorily separated chromatographically, 

Compound Mode0 Achiral column(s) Chiral column References 

Bupivicaine RP Cyanopropyl, C18 ai-Acid glycoprotein Walhagen and Edholm, 1991 

Cyclophosphamide NP Racemic naphthylalanine Chiracel OD Masurel and Wainer, 1989 

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