Meconium is the 1st stool passed by a new born and, as such, represents a record of the fetal environment during the last two trimesters of pregnancy.The authors have developed the 1st capillary electrophoresis (CE) method for the anal. of meconium.This method has the potential to help tremendously in the study of fetal drug exposure.Solid-phase extraction (SPE) was used to extract the drugs (pento-, mepho-, pheno-, seco-, and amobarbital) and the internal standard, hexobarbital, from meconium.The extraction efficiency was studied using C18, C8, SiO2 (Si), and polymeric cartridges for samples buffered at pHs 2.5, 7.0, and 9.0.The polymeric (Oasis HLB) SPE cartridge at pH 9.0 was selected because it gave clean extractions and high recoveries for most of the studied barbiturates.The CE system consisted of a 75 μm I.D. 77 cm length fused SiO2 capillary and a UV detector set at 254 nm.The run buffer consisted of 150 mM tris buffer at pH 7.8 and the run voltage was 25 kV (at 25°).Linear calibration curves show a coefficient of determination of >0.99 for all components.The method also showed high between run and within run precision and accuracy.The limit of quantification was 10 μg per g of meconium.Some common drugs such as aspirin, acetaminophen, and caffeine may be taken in conjunction with barbiturates.The method completely resolved these compounds, along with several other potential interferences, from all the barbiturates in this anal.