DETERMINATION OF DRUG LEVELS IN HUMAN SERUM BY CIRCULAR-DICHROISM

A study of the applicability of circular dichroism (CD) for the determ ination of drug levels in human serum is described and a new method fo r the quantitative determination of optically active absorbing drugs h aving Cotton effects at wavelengths above 250 nm in human serum and/or plasma is proposed. The principal advantages of this method are speed , economy, and simplicity, no derivatization or chromatographic separa tion steps being needed. The validity of the CD determination was conf irmed by analysis of variance, beta-lactam antibiotics being chosen as model drugs. In addition, the validation studies performed confirm th e accuracy and precision of the proposed method. For beta-lactam antib iotics lacking Cotton effects above 250 nm, an alternative method base d on the extraction of the drug from serum is considered. Chirality 10 :507-512, 1998. (C) 1998 Wiley-Liss, Inc.