Micromethod for determination of meperidine in plasma

A GLC method utilizing a flame-ionization detector is described for the analysis of meperidine in blood plasma. Meperidine is extracted with ether from plasma that has been made basic with sodium hydroxide. The ether extract is evaporated to dryness, and the residue is dissolved in carbon disulfide for GLC analysis. An internal standard, N',N'-diethylaminoacetyl-2,6-xylidine, is used to quantitate meperidine. The extraction efficiency from plasma is 85%, and as little as 0.05 microng of meperidine can be quantitatively determined in 1 ml of plasma.