SUPERCRITICAL-FLUID EXTRACTION OF STRYCHNINE USING 2 DIFFERENT SEQUENTIAL ORGANIC MODIFIERS

Carbon dioxide supercritical fluid extraction (SFE) of strychnine from oat grain bait was accomplished using a methanol modifier during stat ic extraction and a chloroform modifier during dynamic extraction. Ext raction efficiency was better than with the use of either modifier alo ne. Analysis time, strychnine recoveries (82%), and reproducibility (S D = 7.8%) were not significantly different from the 85% recovery and 5 .4% SD obtained with a routinely used organic solvent/solid extraction method. The supercritical fluid extraction method generated no hazard ous waste as compared to the solvent/solid extraction method, which pr oduced 50 mt of hazardous waste per sample. This two solvent modifier SFE method resulted in better precision and recovery of strychnine fro m oat bait than other reported SFE methods for the recovery of pestici des from treated grains.