Christensen H
Acta Pharmacol Toxicol (Copenh). 1977 Feb;40(2):289-97. doi: 10.1111/j.1600-0773.1977.tb02081.x.
A method for the simultaneous determination of dextropropoxyphene (DP) and its major metabolite norpropoxyphene (NP) in autopsy material, has been developed. By the extraction procedure used, NP is completely converted to its more stable amide form, which like DP, produces well-defined peaks, in the subsequent gas-liquid chromatographic determination. Thin-layer chromatography is used for additional identification of the two compounds. In 20 g of autopsy material, the detection limit is 0.3 mug/g of tissue or body fluid. The recovery of standards added to control blood samples (1.25 mug/g) was 65 +/- 10% (S.D.) for DP and 59 +/- 9% (S.D.) for NP (n = 54). The method is routinely used for determinations in blood, muscle, liver and urine.