Tolan J W, Eskola P, Fink D W, Mrozik H, Zimmerman L A
J Chromatogr. 1980 Apr 4;190(2):367-76. doi: 10.1016/s0021-9673(00)88241-2.
An analytical method is described for the determination of the avermectins in plasma based upon high-performance liquid chromatography of fluorescent derivatives of these compounds. The analyte is isolated by adsorption chromatography on Florisil, dehydrated in an acetic anhydride-pyridine mixture, and the fluorophore is further separated by chromatography on silica gel in advance of introduction into a reversed-phase system. This method, which can be applied to samples containing as little as 0.2 ng drug per ml, has an accuracy of 5% mean relative error and a precision of 8% relative standard deviation. A study and discussion of several factors which affect the analytical reaction are included.
